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RADIATION THERAPIST, Spring 2011, Volume 21, Number 1

After completing this article, the reader should be able to:

Describe the various biopsy types that require specimen imaging.

List methods of guiding biopsy procedures.

Explain the reasons behind specimen imaging.

Describe various methods for imaging specimens.

Author Sample, B.S.R.T., R.T.(R)(M)(QM)

Best Practices in Digital Radiography

Best Practices

in Digital Radiography

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Best Practices in Digital Radiography

Tracy L. Herrmann, M.Ed., R.T.(R); Terri L. Fauber, Ed.D., R.T.(R)(M); Julie Gill, Ph.D., R.T.(R)(QM);

Colleen Hoffman, R.T.(R)(M)(CT); Denise K. Orth, M.S., R.T.(R)(M);

Paulette A. Peterson, M.Ed., R.T.(R)(M)(QM); Randy R. Prouty, B.S., R.T.(R);

Andrew P. Woodward, M.A., R.T.(R)(CT)(QM); Teresa G. Odle, B.A., ELS

without advance written permission granted by this organization. Send reprint requests to ASRT.

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Best Practices in Digital Radiography 1

Best Practices

In Digital Radiography

he amount of radiation Americans are exposed

to as a result of diagnostic medical imaging

increased about sixfold from 1980 to 2006, and

for the first time in history, estimates of medical

radiation exposure nearly equaled those for background

radiation. The reasons for the increase were varied, and

the highest percentage of collective dose (taking into

account the effective dose and the size of the exposed

population) easily was explained by the corresponding

increase in computed tomography (CT) and nuclear

medicine scanning over the same time period. All the

same, the total number of medical imaging studies rose

dramatically, and radiography was no exception. The

number of radiographic and fluoroscopic studies sky-

rocketed from 25 million in 1950 to 293 million in 2006.

As reports on medical imaging use have been

released, the focus on cumulative dose from regulatory

bodies, clinical societies and the public has intensified,

leading to concerns about utilization of medical imag-

ing. Historically, radiation exposure from diagnostic

medical imaging was not considered a problem, and

there was no evidence that exposure to low doses of

ionizing radiation increased cancer risk. The benefits

of radiography have remained clear over the more

than 100 years of diagnostic medical imaging his-

tory. Another fact that has remained clear is the criti-

cal role that radiographers play in ensuring patient

radiation safety during medical imaging procedures.

Radiographers must adhere to the “as low as reasonably

achievable” (ALARA) principle by keeping radiation

dose as low as is reasonably achievable when perform-

ing digital radiography.

As radiographers have adjusted to the advent of

digital radiography, they have had to refine exposure

technique selection and pay closer attention to radia-

tion protection. Newer digital technologies offer many

benefits over film-screen technology, such as time sav-

ings, greater dynamic range, wider exposure latitude

and postprocessing capabilities, plus advantages such

as image manipulation that enable radiologists to adjust

images at their workstations. As a result, there is a ten-

dency to be less concerned about exposure technique

and the opportunity to use more radiation than neces-

sary, a trend that often is referred to as “dose creep.”

Exposure techniques that radiographers can use to

ensure that digital images are of optimal quality and

minimal patient radiation dose differ from those used

for film-screen imaging. Because digital imaging tech-

nology is relatively new and rapidly changing, radiog-

raphers’ skill levels vary, and resources often are scat-

tered and even conflicting. Radiographers, and their

patients, would benefit from a single source that offers

background information, best practices and recommen-

dations on optimizing digital radiography and patient

radiation safety.

Digital Radiography Background

The first form of digital imaging, digital subtraction

angiography, was introduced in 1977 and put to clini-

cal use in 1980. Today, the term digital radiography in

Tracy L. Herrmann, M.Ed., R.T.(R); Terri L. Fauber, Ed.D., R.T.(R)(M); Julie Gill, Ph.D., R.T.(R)(QM);

Colleen Hoffman, R.T.(R)(M)(CT); Denise K. Orth, M.S., R.T.(R)(M);

Paulette A. Peterson, M.Ed., R.T.(R)(M)(QM); Randy R. Prouty, B.S., R.T.(R);

Andrew P. Woodward, M.A., R.T.(R)(CT)(QM); Teresa G. Odle, B.A., ELS

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Best Practices in Digital Radiography

the literature and in practice encompasses computed

radiography and direct digital radiography. Computed

radiography (CR) is a system that replaced film with a

storage phosphor plate as the image receptor. The latent

image on the exposed plate is scanned by a laser beam

and converted to digital data to produce the image.

Direct digital radiography (DR), which also might be

further classified as direct and indirect image capture,

involves acquiring image data in digital format, without

laser scanning to extract the latent image.

In CR, storage phosphor image plates were first used

to record general radiographs in 1980. The direct cap-

ture of x-rays for digital images was introduced with DR

using of a charge-coupled device in 1990. The technol-

ogy evolved and improved over the next decade and

by 2001, flat-panel thin-film transistor detectors could

expose and display images in near real time. Growth in

digital image receptors has risen slowly and steadily, and

within a few years could increase to double-digit annual

rates. Today’s technology includes a variety of devices

and materials such as storage phosphor plates, charge-

coupled devices, thin-film transistors, photoconductors

and x-ray scintillators. Cassette-based and cassette-less

systems have blurred the lines between CR and DR.

An analysis by the technologies market research firm

Technavio reported that the global digital radiography

market could increase by a compound annual growth

rate of 3.3 percent through 2014. The complexity of the

operation of these systems has created misconceptions

about the best practices for the use of digital radiography.

In general, radiography examinations represent

74 percent of all radiologic examinations performed

on both adults and children in the United States, and

contribute to about 40 percent of radiation exposure.

Although much attention in recent years has focused

on lowering CT dose in particular, the prevalence of

radiographic examinations, exposure and a rise in transi-

tion to digital image receptor technology necessitates a

thoughtful and thorough examination of best practices

for radiographers regarding digital exposure techniques

and radiation safety.

Dose

When following the ALARA principle, radiogra-

phers should minimize patient exposure from digital

radiography procedures. The use of digital image recep-

tors can result in lower radiation dose than the use

of film-screen image receptors, without loss of image

quality. Using digital image receptors requires careful

and consistent attention to institutional protocol and

practice standards, however. Conventional film-screen

radiation exposure techniques are based on the specific

film-screen system and the conditions under which the

radiographer processes the film. Digital radiography

separates acquisition, processing and display, which

enables a radiographer to produce an image that has

acceptable diagnostic quality, but could be underex-

posed or overexposed. Adjustments to compensate for

exposure technique errors can be made at the time of

display, although doing so is not a best practice. The

best practice is to select the appropriate exposure

technique factors for the patient’s size and condition,

based on a planned exposure system designed in col-

laboration with radiologists, to determine adequate

image quality for diagnosis.

Image quality depends heavily on contrast, or the rel-

ative differences in brightness or density in the image.

Image contrast has two primary components, subject

contrast and display contrast. Subject contrast is related

to the absorption of the x-ray beam by the subject’s tis-

sues. Display contrast can be adjusted in postprocessing

and by adjusting the monitor display’s window width.

Very low contrast (many shades of gray) makes it diffi-

cult for a radiologist to differentiate between structures

and identify anomalies or pathologies; an image must

have contrast to demonstrate different structures and to

be diagnostically useful. Very high contrast reduces the

image to a scale of mostly black-and-white brightness

or densities, which hinders visibility of the anatomic

details. In digital imaging, contrast is the ratio of bright-

ness of adjacent structures to one another, and gray

scale represents the range of brightness levels.

Subject contrast is determined by different absorp-

tion of the x-ray beam by various tissues, anatomic

thicknesses and tissue densities in the body and the

penetrability of the beam primarily controlled by kVp.

Unlike image contrast, subject contrast cannot be

manipulated or recovered with postprocessing; it is

directly affected by how the x-ray beam is attenuated in

anatomic tissues, such as bone and soft tissue.

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Best Practices in Digital Radiography

dose. Radiographers also need access to collected and

standardized information at the institutional and nation-

al levels to help them better navigate the transition to

the best practices for radiation safety in digital imaging.

Avoidance of repeat exposures, careful use of shielding

and beam restriction, clearly established accepted ranges

for exposure indicators (EIs) and other practices will be

covered in the Best Practices discussion below.

Social Marketing and Radiation Safety

Initiatives

Issues such as dose creep have not gone unnoticed.

National and global attention have focused on medical

radiation, and several initiatives have begun educating

radiographers, physicists, radiologists, referring physi-

cians and the general public. One such initiative, the

Image Gently campaign sponsored by the Alliance for

Radiation Safety in Pediatric Imaging, began in 2008

to promote radiation protection for children who have

received medical imaging procedures. With an initial

focus on reducing radiation dose to children undergo-

ing CT examinations, the campaign soon progressed

to fluoroscopic and interventional procedures, nuclear

medicine and other medical imaging including routine

digital radiography. In 2011, the campaign released a

safety checklist for performance of DR examinations

on pediatric patients. More than 14,000 medical pro-

fessionals have taken a pledge to minimize radiation

dose to children and the campaign’s pediatric CT pro-

tocol has been downloaded from its website more than

26,000 times. More recently, the American College

of Radiology (ACR), ASRT, American Association

of Physicists in Medicine (AAPM) and Radiological

Society of North America jointly developed the Image

Wisely campaign to lower the amount of radiation used

in medically necessary imaging and to eliminate proce-

dures that are unnecessary.

Much of this change was brought about by media

reports linking CT scans to childhood cancer. However,

once ionizing radiation from medical imaging moved

into the public arena, medical professionals could no

longer deal with the matter in isolation. According to

the ACR, the radiology community alone had focused

on patient radiation safety issues until these potential

hazards were publicized. Other members of the medical

The ability to adjust display brightness and contrast

during postprocessing can affect radiographers’ atten-

tion to the primary principle of radiation protection:

optimal image quality with minimal patient exposure.

Radiographers must pay careful attention to all aspects

of radiographic exposure technique to provide diagnos-

tic image quality and minimize patient exposure, help-

ing to maximize benefit over potential harm. In addi-

tion, the wider range of radiation intensities that digital

image receptors can detect has allowed for a wider range

of values to be processed digitally to display a diagnostic

quality image. Because image receptor exposure infor-

mation is not apparent from the examination or record-

ed for each digital examination, there is a further discon-

nect between image capture and the resulting patient

exposure. A best practice in digital radiography is

the consistent inclusion of information regarding the

image receptor exposure in the image data provided

throughout the image archiving process.

In digital radiography, the computer automatically

adjusts an image that is overexposed to ensure that the

image is of diagnostic quality. This automatic adjust-

ment, separation of image acquisition and display and

lack of available dose information can contribute to

increased patient exposure. What’s more, an exces-

sive exposure to a patient during a digital radiography

examination does not affect image quality, except at

extremely high levels of exposure. In fact, the decreased

image noise that results from additional exposure can

lead to a corresponding decrease in complaints from

radiologists regarding image quality. In turn, radiogra-

phers might be inclined to adjust exposure technique

to slightly increase the amount of radiation and subse-

quently patient radiation dose.

These factors have contributed to dose creep and a

gradual increase in patient exposure. Radiographers,

often faced with feedback that unwittingly reinforces

slight overexposure and lacking the visual cues that

density offered in film-screen imaging, often choose

the path of least resistance: increased exposure tech-

nique, decreased chance of image noise and avoidance

of repeats.

Many standard practices and the control of dose

creep require careful review and strict adherence to

sound radiation safety practices to minimize patient

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Best Practices in Digital Radiography

In 2010, the U.S. Food and Drug Administration’s

(FDA) Center for Devices and Radiological Health

began an initiative to decrease unnecessary exposure

from medical imaging procedures.As a result the

FDAhas supported the development of educational

materials and a safety checklist for digital radiography

via the Image Gently campaign. The FDA also has

recommended that manufacturers design medical

imaging equipment with pediatric populations in mind.

Through education, research and reports in the litera-

ture and change in practice, culture change can occur.

Much work still can be done to compel the culture and

practice changes needed to ensure radiation safety and

minimize patient dose in digital radiography.

ACR Practice Guideline for Digital

Radiography

The ACR developed a practice guideline for digital

radiography in 2007. The document’s intent was “to

provide guidance and assistance in the understanding

and clinical use of digital radiography equipment in

order to deliver optimal image quality at appropri-

ate radiation doses, and to ultimately provide excel-

lent safety and care for patients undergoing digital

radiography examinations.” In general, ACR practice

guidelines for any examination or process undergo

literature and field review, summary of expert opinion

and informal consensus that results in recommended

conduct. The guidelines are not intended to be legal

standards of care; providers can use them as the basis

for practice and modify them according to individual

circumstances and resources.

The ACR guideline on digital radiography provides

information lost in the gap between film-screen and

digital imaging, and some of the key points of the

guidelines are included in this paper. By clearly outlin-

ing information such as personnel qualifications, grid

use, prevention of dose creep and determining proper

exposure factors, the guidelines laid the groundwork

for facility protocols and standardization of digital

exposure technique. The ACR guidelines also com-

pare film-screen and digital technologies, helping

radiographers and other medical professionals better

understand the nuances they face in working with

digital imaging.

community and the public now see the issue more

clearly. Multiple organizations and individuals have

worked together to address the problem. The Alliance

for Radiation Safety in Pediatric Imaging, which was

founded by four imaging organizations, continues to be

a leader in radiation safety initiatives.

There also have been international efforts to

improve medical radiation safety. The United Nations

Scientific Committee on the Effects of Atomic

Radiation (UNSCEAR) published a report in 2010 that

described a strategic plan through 2013. UNSCEAR

asked the public, authorities and scientists to be more

aware of radiation dose in medicine. At a 2010 meet-

ing, UNSCEAR called for improved data collection,

analysis and dissemination of information for patients

and those exposed to radiation occupationally. The

International Commission on Radiation Protection

has updated reports and recommendations and the

International Atomic Energy Agency launched an

action plan in 2002 aimed at reducing patient exposure

to radiation. The plan included an informational web-

site for patients about radiation protection.

The World Health Organization (WHO) joined

with other organizations and agencies in 2010 in calling

for global sets of evidence-based referral guidelines for

medical imaging. The European Commission com-

mitted to developing guidelines for its member states

and has aimed to compel member states to adapt their

national regulations and quality assurance programs to

meet more standardized and stringent requirements.

The Society for Pediatric Radiology held a 2004

white paper conference on Feb. 28, 2004, in Houston,

Texas, that summarized the need to emphasize the

ALARA principle in digital imaging. The white paper

conference faculty recommended a team approach to

dose management. Other recommendations included

improved training of radiographers and standardiza-

tion of nomenclature among manufacturers to assist in

understanding and minimizing dose, improved dose

feedback, and development of standards in digital

radiography. The findings and recommendations were

published in an October 2004 supplement to Pediatric

Radiology, the December 2004 issue of Radiologic

Technology and the February 2005 issue of the American

Journal of Roentgenology.

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Best Practices in Digital Radiography

who perform digital radiography examinations. This

white paper is not, however, an all-inclusive document,

nor should any of these recommendations be taken as

superseding institutional policy or state regulations. In

addition, much like digital technology, it is meant to be

a fluid, living document.

Step-by-Step Best Practices

Radiographers need to take responsibility for under-

standing and appropriately performing digital radiogra-

phy procedures because it is their professional duty and

an essential component of the radiographers’ practice

standards and code of ethics. Aside from preparing for

digital radiography examinations through attainment of

proper education and skills sets, there are a number of

ways before, during and after examinations that radiog-

raphers can optimize exposure technique and minimize

radiation exposure.

Before the Exam Begins

Because radiographers usually are the first, and often

the only, medical professional to interact with patients

who are scheduled for radiology examinations, radiog-

raphers are charged with a great deal of responsibility

even before examinations begin. Ensuring that patient

radiation safety is maintained and exposure minimized

requires regular attention to several matters before cap-

turing the images. Some of the issues are common to

the film-screen environment, but reiterated here.

Procedure Validity

As a patient advocate and the last medical profes-

sional to potentially screen for appropriateness before

performing an examination, the radiographer has

a responsibility to recognize and take action when

an incorrect exam is ordered. In an ASRT survey of

radiographers conducted for the Image Gently cam-

paign, nearly 12 percent of respondents cited “unneeded

exams ordered by doctors” as contributing to or causing

excess radiation exposure when performing pediatric

digital radiography. Inappropriate diagnostic imaging

examinations unnecessarily add to cumulative radiation

dose in patients. The radiographer might be the only

person who has the opportunity to recognize that the

examination is a duplicate or is questionable in terms

Scope of White Paper

The ASRT has championed radiation protection in

digital imaging for all age groups through its support

of and participation in the Image Gently and Image

Wisely campaigns. In addition, ASRT has a continued

history of promoting these areas of professionalism

through publication of educational and promotional

materials for the public and the medical imaging com-

munity. The Consistency, Accuracy, Responsibility and

Excellence in Medical Imaging and Radiation Therapy

(CARE) bill can help provide the foundation for nation-

al uniformity of licensure laws. The ASRT supports

efforts toward the passage of the CARE bill to promote

minimum standards in each state that ensure only edu-

cationally prepared and clinically competent radiologic

technologists perform radiographic examinations and

radiation therapy procedures. This white paper is a

significant continuation of ASRT’s dedicated efforts in

promoting radiation protection for patients and profes-

sionalism for radiologic technologists.

This white paper combines information from trusted

sources such as the ACR guidelines, textbooks, profes-

sional and government organizations and periodical

literature on exposure technique and patient exposure.

The information gathered aims to support preparation

of radiographers for digital radiography practice and to

examine digital radiography’s best practices for a balance

of optimal image quality and patient radiation safety.

Radiographers assume extensive responsibility in the

radiation safety of patients. The ACR white paper on

radiation dose in medicine places final responsibility for

additional action before radiation exposure on radiog-

raphers. Further, the paper states that “technologists are

responsible for limiting radiation exposure to patients

by ensuring that proper procedures and techniques are

followed… .”

Radiographers who perform digital radiography

examinations must recognize their responsibility in

understanding how to optimize digital images while

minimizing radiation dose to patients. As the “experts”

on exposure technique in radiology teams, radiogra-

phers should be proactive in remaining up-to-date on

the basics of radiation protection and new technologies.

The best practices and recommendations included

in this white paper serve as a resource for radiographers

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Best Practices in Digital Radiography

health history with the patient. Important informa-

tion can be obtained by asking routine questions of the

patient to further validate the ordered examination and

to determine whether the patient should have an exami-

nation that involves radiation. It is a best practice in

digital radiography for the radiographer to carefully

review the examination ordered to prevent potential

duplication and to ensure appropriateness as related

to the patient’s history. If there is a possibility that the

examination might be inappropriate, the radiogra-

pher then should consult with the radiologist and/or

ordering physician to ensure the appropriate exami-

nation is being obtained.

Departmental Standards and Protocols

National or international guidelines and accredita-

tion requirements provide the foundation upon which

radiology departments can base their specific proto-

cols for all imaging examinations, including digital

radiography examinations. For example, if a radiology

department does not develop exposure technique

charts or make them available to radiographers, it is

more difficult for radiographers to manually set mil-

liampere seconds (mAs) and optimal kilovoltage peak

(kVp). When systems have automatic exposure control

(AEC), other variables such as AEC detector cell con-

figuration and backup time also can be standardized.

Departments should establish protocols for common

digital radiography examinations and conspicuously

post them for radiographers’ use.

Radiographers should expect to consult with radi-

ologists and vendors to refine information provided

by vendors for exposure techniques and protocols.

Nuances in equipment, personal preference and learn-

ing curves for digital technology all could be factors

that contribute to inconsistencies in exposure tech-

niques. The best way for a radiographer to ensure con-

sistency is by following department protocols that are

based on established clinical research and guidelines.

Advantages of digital radiography include the ease

of incorporating images and order entry into exist-

ing radiology information systems (RIS) and picture

archiving and communication systems (PACS). In

many ways, this has positively affected radiology

department workflow, eliminating many manual

of indication or appropriateness. Radiographers should

consult with the radiologist or ordering physician or

request additional information from the ordering physi-

cian that can further indicate the correct procedure to

be performed when there is a suspicion of an inappro-

priate exam order.

On a broader scale, increased utilization of diagnos-

tic medical imaging has added to increased patient radi-

ation doses. A higher frequency of high-dose examina-

tions can directly affect individual and collective dose.

The issue of imaging overutilization is being addressed

globally with calls for standardizing of image justifica-

tion, along with social media campaigns and interven-

tion of payers or other third parties.

Organizations such as the ACR have addressed

utilization by developing guidelines to help referring

physicians select the appropriate imaging procedure.

An example is the ACR Appropriateness Criteria,

evidence-based guidelines developed by panels of

experts in imaging; the criteria cover several types of

diagnostic imaging and therapeutic uses of imaging and

ionizing radiation. The World Health Organization has

proposed development of global guidelines for appro-

priate referrals to medical imaging. WHO hosted a

conference in March 2010 with 36 experts from around

the world; the experts recommended development of

the guidelines under WHO’s umbrella. The guidelines

are expected to include radiation dose level for exami-

nations, along with efficacy ratings and a grade for

strength of existing evidence regarding each examina-

tion’s efficacy.

Tracking of previous examinations also can help

radiographers identify duplicate examinations before

beginning the procedure. Reviewing health records

can help spot duplicate examinations, but patients may

have imaging examinations performed by any number

of providers within a given time period. Many inter-

national organizations and agencies have approved or

developed systems that track radiographic procedures

in a fashion similar to vaccination records. Using a

system-based approach that standardizes input from

providers rather than patients could help facilitate iden-

tification of duplicate examinations and recording of

cumulative dose. In addition to identifying duplicate

examinations, a radiographer must review the patient’s

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Best Practices in Digital Radiography

Screening for Pregnancy

As with film-screen radiography, the radiographer

needs to carefully review the patient’s history before

beginning the digital examination to determine wheth-

er the patient is pregnant. How to verify pregnancy

varies slightly according to department protocol, but

typically includes asking women of childbearing age if

there is any possibility they are pregnant. The radiogra-

pher can use physical signs and lead-up questions to aid

in determining possible pregnancies. Tact and profes-

sional communication help put the radiographer and

the patient at ease.

The exact protocol for proceeding once a patient

responds that she might be pregnant is specific to the

department. Departments often require written docu-

mentation before pregnancy screening can occur, and

the patient’s referring physician or radiologist generally

decide whether pregnancy testing is necessary. The

physicians also decide whether the patient should have

an alternative imaging examination to avoid radiation

exposure. The screening of patients for potential

pregnancy is an essential best practice for radiation

safety in digital imaging.

Image Acquisition

The foundations of radiographic exposure technique

selection don’t change simply because a radiographer

uses a different type of image receptor. When produc-

ing images using digital technologies, radiographers

still must determine the radiation exposure needed to

produce a quality image for diagnostic interpretation. A

quality image has sufficient density/brightness to dis-

play anatomic structures, an appropriate level of subject

contrast to differentiate among the anatomic struc-

tures, the maximum amount of spatial resolution and a

minimal amount of distortion. In addition, limiting the

amount of quantum noise/mottle as a result of too few

x-rays reaching the image receptor is a common concern

in digital imaging. Many variables affect the acquisition,

processing and display of a quality image and the advent

of digital imaging has created new challenges for the

radiographer.

Digital imaging technologies continue to evolve and

vary in their construction and how the latent or invis-

ible image is acquired. Common digital image receptors

steps and improving patient care and efficiency.

For example, in facilities that have a RIS, electronic

health records (EHRs) and a PACS, the process from

order entry to report generation involves little to no

human interaction. The RIS and modality worklist

system schedules a worklist for the digital radiography

equipment, which bundles the information with the

acquired images and sends it to the PACS. This infor-

mation is available at the radiologist’s workstation, and

if the radiologist uses speech recognition software,

the report is generated automatically for radiologist

approval, then archived and distributed to referring

physicians through the EHR.

The lack of human interaction is one reason that

adopting a new technology and automating various

ordering and hand-off processes can be less disrup-

tive to patient care and decrease the potential for

errors. Another is that the transition to a digital

environment streamlines workflow. The transition

from a film to a digital radiography environment can

initially be very daunting when digital radiography

is the first, only or final modality transitioned in a

given radiology department, it is imperative to take

steps to assess, prepare and establish procedures for

digital image interpretation and storage. This prepa-

ration should involve technologists, who must have

the proper tools and procedures in place to do their

jobs correctly.

Though digital technologies simplify workflow,

planning for workflow adjustments is critical. It begins

with looking at current workflows for acquiring and

interpreting images, along with quality assurance

(QA). Radiographers and other team members must

decide whether to attempt to duplicate workflow with

digital technologies or improve them. They also must

work together—and with vendors—to identify poten-

tial gaps in workflow or function. The team must then

document the workflow and standardize protocols

and procedures. Radiographers must follow the

protocols and standards set by their departments

and actively participate in establishing and further

developing protocols that ensure consistency of

diagnostic quality images and improved practices

to reduce patient radiation dose. This is a critical

best practice in digital radiography.

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Best Practices in Digital Radiography

needed to create the differences in x-ray energies exiting

the part to produce the desired level of contrast. Given

adequate penetration of the part, kVp has less of an

effect on the contrast of the image because of computer

processing. A quality digital image is produced follow-

ing adequate penetration (kVp) along with enough mAs

to produce a diagnostic image with a minimal amount

of quantum noise/mottle.

The use of higher kVp values along with an appropri-

ate decrease in mAs is a practice advocated by some

imaging professionals for many adult digital exams.

Increasing the kVp by 15% with a corresponding

decrease in mAs reduces patient radiation exposure.

Because increasing kVp decreases image contrast and

increases scatter radiation reaching the image receptor,

the use of a grid may be necessary. Specifying the kVp

level for digital exams along with grid use are important

exposure technique variables to standardize in a radiol-

ogy department. A best practice in digital imaging is

to use the highest kVp within the optimal range for

the position and part coupled with the lowest amount

of mAs needed to provide an adequate exposure to

the image receptor.

Automatic Exposure Control

The AEC for digital radiography systems operates

identically to AEC used for film-screen systems. It is

critical that the AEC be properly calibrated to match

the image receptor system before clinical use. AEC sys-

tems use radiation detectors called ionization chambers

that are preprogrammed based on phantoms. These

systems traditionally come equipped with three ion-

ization chambers; some newer AEC systems have five

detectors from which to choose. It is important that

radiographers choose the appropriate detector configu-

ration for the examination.

The purpose of AEC is to control exposure time, so

use of this feature is critical to patient radiation safety.

AEC helps control total mAs, but the radiographer

still is responsible for selecting optimum mA (if set)

and kVp for an examination when using AEC, and

technique charts help ensure consistent use of these

factors with AEC. Although AEC use is recommended

in most radiographic examinations to help reduce

patient radiation exposure, there are times when it

in routine radiography include computed radiography

photostimulable image receptors, charge-coupled

devices and flat-panel thin-film transistor detectors.

Because the technology is changing rapidly, digital

image receptors will be discussed in general and specif-

ic differences among detectors will be described when

appropriate. Standardizing exposure technique and

emphasizing sound practices can help ensure a radiog-

rapher follows the ALARA principle when performing

digital examinations.

Standardized Exposure Technique

A digital image receptor responds to a large variance

in x-ray intensities exiting the patient. As a result, the

digital image receptor also has a wide dynamic range.

In addition, computer processing produces “accept-

able” images even when significant overexposure has

occurred. Because of this, the standardization of expo-

sure techniques used in a radiology department has

become even more essential. Digital technologies are

progressing rapidly, and departments cannot rely solely

on vendors and professional organizations to set techni-

cal standards. Setting department policies and protocols

helps the radiology department ensure consistency in

diagnostic quality of digital examinations and minimizes

the potential for exposure technique selection errors.

Standardizing exposure techniques, however, does

not mean that radiographers use the same protocols for

all patients in all situations. Exposure techniques must

be adjusted for a patient’s specific history and condition.

Appropriate and consistent use of exposure technique

charts, adequate kVp and AEC is essential to consis-

tently producing diagnostic images while minimizing

patient radiation exposures.

Kilovoltage Peak (kVp)

Image quality is dependent on a sufficient amount

and energy of x-rays reaching the image receptor. As a

general rule, kVp and mAs should be selected for digital

radiography in the same manner as the exposure factors

are selected for film-screen image receptors. However,

the amount of exposure (mAs) to the digital image

receptor does not directly affect the amount of density/

brightness produced as a result of computer process-

ing. Adequate penetration of the anatomic part (kVp) is

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to assess the programmed exposure technique for its

appropriateness to each radiographic examination.

An exposure technique chart also can be used to

standardize exposure techniques according to patient

size, procedure and position. Use of exposure technique

charts is required in some states and as a standard of

care per The Joint Commission. Departments can pro-

vide the charts with relatively simple spreadsheets that

are posted and accessible to radiographers. Although

exposure technique charts take time and effort to

develop accurately, they prevent exposure technique

errors. Routine use of the charts can provide consistent

and accurate radiation exposure to the image receptor,

thereby reducing patient dose.

Providing exposure technique charts establishes

department standards and eliminates much of the

confusion and concern regarding appropriate use

of variables such as kVp, mA, grid use and SID. The

charts also allow radiologists and technologists to work

together to determine an acceptable level of radiation

exposure that provides diagnostic quality images within

the ALARA principle. A thorough exposure technique

chart includes, at a minimum, the following variables

for each x-ray tube:

 Backup exposure time or mAs (if set).

 Source-to-image receptor distance (SID).

 kVp.

 Focal spot size.

 mA (if set).

 Use of a grid and the grid ratio.

 AEC detector(s).

 Acceptable exposure indicator range.

Typically, exposure technique charts are developed

based on patient thickness. Although measuring patient

thickness in adult imaging may not be practical in all

departments, well-developed charts that are consis-

tently used can reduce the variability in exposure tech-

niques that occurs during digital imaging. The charts

don’t take the place of radiographers carefully assessing

individual patient pathology, condition and unusual

circumstances because exposure technique charts are

designed for the average or typical patient. Exposure

technique charts should be monitored and revised con-

tinuously to ensure exposure techniques are producing

diagnostic images within the ALARA principle. A best

can’t be used. For example, if the anatomy of interest

is too small to cover at least one of the AEC’s detector

cells, AEC will not work and should not be used.

If AEC is used when the anatomy of interest is too

small, those areas of the detector not covered by the

patient’s anatomy receive more radiation than the area

of interest, causing the AEC to terminate the exposure

time prematurely and causing quantum noise in digital

images. This is especially important to consider when

performing pediatric radiography. Using AEC to image

anatomy close to the edge of the patient’s body, such

as the clavicle, also can cause the time of exposure

to prematurely terminate and result in insufficient

exposure to the image receptor resulting in increased

quantum noise. Finally, presence of large metal artifacts

such as orthopedic hardware can contraindicate the

use of AEC. Unless large metal objects can be moved

away from the area of interest, they create unexposed

areas over the AEC detectors that can affect the time of

exposure and potentially overexpose the patient.

Although use of the unit’s AEC is the best way to

control the amount of radiation exposure regardless of

the type of image receptor, doing so requires accurate

positioning and systematic calibration of the AEC.

Radiographers should ensure that the anatomy of

interest covers most of the AEC detector(s) used, and

place emphasis on proper positioning for an exami-

nation. It is important for radiographers to follow

department protocols and exposure technique charts

regarding use of AEC. A best practice in digital radi-

ography is to use AEC when indicated and to use

AEC that has been calibrated to the type of image

receptor to provide a consistent exposure to the

image receptor.

Anatomically Programmed Radiography and

Exposure Technique Charts

Anatomically programmed radiography (APR) is

a system of preprogrammed exposure technique set-

tings that is organized by position and procedure and

set through the control panel of the radiography unit.

APR settings commonly provide recommendations

for small, medium and large adult patient sizes and

include a combination of AEC and manual exposure

technique settings. It is important for the radiographer

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Best Practices in Digital Radiography

the radiologist. When multiple fields are included on one

image receptor, radiographers should keep the exposure

fields aligned, avoid overlapping fields and use flex-

ible lead shielding on all areas of the receptor not being

exposed by the x-ray beam, regardless of image receptor

technology. The literature includes several reports stat-

ing that the use of collimation that uses a smaller field

size could help lower radiation doses to patients.

A best practice in digital radiography is to colli-

mate the x-ray beam to the anatomic area appropriate

for the procedure. Electronic masking to improve

image viewing conditions should be applied in a man-

ner that demonstrates the actual exposure field edge

to document appropriate collimation. Masking must

not be applied over anatomy that was contained in

the exposure field at the time of image acquisition.

Shielding

Lack of patient shielding can contribute to increased

patient dose. Shielding is particularly important to protect

anatomic areas near the exposure field, but should not

interfere with obtaining diagnostic information. At a min-

imum, a patient’s gonads should be shielded when within

5 cm of the edge of a properly collimated x-ray beam.

Radiographers should follow department guidelines

for proper shielding. This is particularly critical for

digital examinations because shielding can interfere

with the equipment’s ability to optimize display for the

region of interest if the shielding material is included as

part of the data used for processing the image. Shielding

is a fundamental radiation safety practice that remains

important when performing digital radiography. A

best practice in digital radiography is the use of lead

shielding for anatomic parts that are adjacent to the

x-ray field.

Anatomic Side Markers

Radiographers should use lead anatomic side

markers that are placed on the image receptor

for digital radiography examinations. Electronic

annotations of anatomic side on the image during

postprocessing are not an acceptable substitute for

lead markers captured during the exposure to the

image receptor as part of the original image. Failing

to use lead markers to denote the side or to identify

practice in digital radiography is to use exposure

technique charts that are continuously improved and

applicable to a wide range of patient sizes.

Collimation and Electronic Masking

It is essential that radiographers carefully use col-

limation to the appropriate anatomy of interest when

performing digital examinations to minimize patient

exposure and prevent errors in processing of the digital

image data. By limiting the anatomy that receives radia-

tion, a smaller area of the patient’s tissue is exposed,

thereby reducing patient dose and minimizing scatter

radiation to the image receptor. Collimation is very

important in digital radiography because digital image

receptors are more sensitive to low levels of radiation,

and the resulting digital image might demonstrate

reduced image contrast because of excess scatter radia-

tion striking the receptor.

Digital radiography systems have software that pro-

vides electronic masking (collimation) based on recog-

nition of the borders of the exposed area of the image

receptor; radiographers may need to adjust the electron-

ic masking to accurately align it to the exposure field.

The unexposed area of the image outside of the collimat-

ed exposure field has a bright appearance on the display

monitor that affects viewing conditions. The purpose

of the masking is to reduce the eye strain of the viewer

caused by high brightness levels. To document appropri-

ate collimation for an examination, the mask should be

applied to the image with a small distance between the

exposure field and the start of the mask overlay.

Masking, shuttering or cropping should not be used

as replacements for beam restriction achieved through

physical collimation of the x-ray field size. The appro-

priate use of masking is to act as an overlay on the areas

outside of the collimated exposure field; masking never

should be used to cover anatomy that is contained with-

in the exposure field at the time of image acquisition

because of legal and radiation safety concerns.

The appropriateness of including multiple exposures

on one image receptor depends on the type of image

receptor being used. If the image receptor is capable of

acquiring more than one image prior to image process-

ing, the decision to do so should be determined by the

department protocol established in consultation with

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Best Practices in Digital Radiography

the radiographer performing the examination can be

a legal issue. The ACR also emphasizes consistent

use of lead markers in its digital practice guidelines. A

best practice in digital radiography is the consistent

use of lead anatomic side markers captured on the

original image during the x-ray exposure.

Grids

The fact that digital imaging technology is more

sensitive to low-level radiation exposure makes the use

of antiscatter grids critical to ensuring quality images.

A major disadvantage of using a grid is the required

increase in radiation exposure to the patient. However,

using a grid decreases the amount of scatter radia-

tion that reaches the image receptor and improves

image quality. Department guidelines and exposure

technique charts should assist radiographers in deter-

mining whether to use grids for specific radiographic

examinations. As a general rule, grids are appropri-

ate for anatomy that is 10 cm thick or more and for

examinations using kVp settings of 70 or higher. Grid

use could vary for pediatric patients, however, or

based on department protocol or recommendations of

the equipment vendor. In addition, it is important to

consult with the vendor to match the appropriate grid

design to the digital imaging system to prevent arti-

facts. A best practice in digital imaging is the use of a

grid with specifications recommended by the digital

imaging equipment vendor, generally for body parts

that exceed 10 cm.

Positioning

Accurate positioning is critical to radiographic

image quality. Positioning errors have been identified

in several studies as the number one reason for hav-

ing to repeat digital radiography examinations. The

increase in exposure latitude in digital radiography

seems to have led to an overall reduction in repeats,

and the cause of most repeat imaging has shifted to

positioning errors. Inaccurate positioning of the part

relative to the image receptor, along with a poorly

collimated exposure field, often results in poor qual-

ity digital images. Independent of the image receptor

system, it is critical that all positioning be performed

accurately according to national standards and depart-

ment protocol with accommodation for the patient’s

condition to prevent the need for a repeat exposure.

Immobilization is a critical component of position-

ing that helps to prevent retakes, particularly in exami-

nations of pediatric patients. The radiographer must

note that some immobilization devices used in posi-

tioning patients, such as sandbags and sponges with

plastic coverings, can cause artifacts in digital imag-

ing and must be kept out of the exposure field. A best

practice in digital imaging is to use immobilization

devices when needed and prevent repeat exposures

by appropriately positioning the patient.

Considerations for Pediatric Patients

Pediatric patients are not just small adults; they

require special attention from the radiographer.

Therefore, many of the factors radiographers must con-

sider during adult radiographic examinations should be

given special consideration when performing radiogra-

phy of pediatric patients. Pediatric patients have devel-

oping organs and are up to 10 times more sensitive to

ionizing radiation than are adults. They also have longer

life expectancies, so attention to ALARA for pediatric

digital examinations is essential.

Beam Attenuation and Tissue

Tissue thickness, body habitus and tissue composi-

tion result in differences in x-ray beam attenuation.

This is the basis on which digital and all radiologic

imaging creates radiographs. For example, muscle tissue

is more dense than fat tissue, and requires an increase

in technique so that the beam can adequately pen-

etrate the muscle tissue, regardless of the patient’s size.

Reconfiguring techniques applied to adult tissues for

use on children does not work; the dimensions of chil-

dren’s anatomies vary much more than those of adults.

This makes it difficult to estimate exposure technique

because patient thickness depends not only on a child’s

age, but also on the child’s individual characteristics.

In addition to the variation in growth along the age

continuum and from one child to another, children’s

body parts grow at different rates. For example, the

femur of an infant is one-fifth the size of an adult femur,

and represents the extreme in development from birth

to adulthood. On the other hand, an infant’s skull grows

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Best Practices in Digital Radiography

more slowly, only tripling in size by adulthood. Grids

typically are not used when anatomy is less than 10 cm

thick, so radiographers must carefully consider whether

to use grids based on the patient’s actual size and tissue

composition. Because the tissue composition is differ-

ent in pediatric patients, a grid should not be considered

for body parts less than 12 cm in thickness.

Exposure Technique

In pediatric radiography, APR and exposure

technique charts must be adjusted for patients who

may vary from premature infants to obese adults.

Radiographers must carefully select optimal kVp

to penetrate the pediatric patient’s anatomy under

study. Selection of appropriate kVp is more critical

with exams of infants and children because their bod-

ies typically display less subject contrast. Infants and

young children have bones with less calcification than

adult bones, which requires lower kVp compared to

that required in adult exams. As a result, radiographers

can reduce kVp, but still adequately penetrate the bone

with the x-ray beam for a diagnostic-quality image.

Adult AEC settings cannot be used for pediatric

patients. Radiographers who use AEC settings for

imaging pediatric patients should follow the Imaging

Gently digital safety checklist, which emphasizes

that radiographers must be diligent in ensuring that

the appropriate kVp, backup time, image recep-

tor and detector (or detectors) have been selected.

Radiographers may need to use manual technique

selection in pediatric radiography when the part is

smaller than the ionization chamber.

Collimation/Shielding

Appropriate collimation and minimizing the anat-

omy exposed to radiation can reduce radiation dose to

pediatric patients. As with adult examinations, proper

alignment is critical to ensure essential anatomy is

included in the image. Studies have found that poor

collimation of lumbar spines led to unnecessary radia-

tion exposure for children. Proper shielding also can

help reduce dose. Lap shields and half-shields can help

protect children’s gonads. Specially shaped shields

can be helpful for male gonads or female breasts. It is

important, however, with some digital radiography

systems that shields not interfere with the software’s

ability to identify the exposure field. Protocols may

be established that allow for the use of a shield on one

projection when multiple projections in the same area

of the gonads are required. Radiographers should fol-

low department protocols regarding collimation and

shielding for pediatric examinations.

Positioning and Immobilization

Because pediatric patients have more trouble com-

plying during positioning and image capture, the

anatomy might not be centered accurately or consis-

tently within collimation boundaries compared with

adult positioning. In some digital imaging systems,

improper centering affects how the digital system soft-

ware forms the image. Immobilization devices may

help ensure that the pediatric patient can be imaged

without need for repeat. However, care needs to be

taken when using some standard immobilization aids

that can create artifacts on digital image receptors. A

variety of toys, books and other distraction tools also

can be used to help comfort or focus pediatric patients

to support their compliance with the positioning

requirements of the procedure.

A best practice in pediatric digital radiography is

to take appropriate actions to use ALARA principles,

radiation protection, and size-appropriate exposure

techniques. Proper positioning and immobilization

also are necessary to decrease repeat exposures.

Image Critique

Radiographers must ensure that they thoroughly

critique their radiographs to review each image for the

following:

 Correct patient and examination information.

 Brightness/contrast.

 Exposure indicator.

 Processing errors.

 Required anatomy.

 Positioning accuracy.

 Artifacts.

In short, the radiographer’s review is important to

ensure that the images contain the information the radi-

ologist needs to interpret the image for pathology and

clinical reporting.

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Image Appearance

The visual cues of underexposure and overexposure

errors are more difficult to recognize or are missing

in digital radiography as a result of what happens to

the image data during imaging processing. A com-

mon misconception is that the digital system “fixes”

exposure errors, when in fact it does not. During the

analysis of the image data, the potential exists for the

digital system to make adjustments to the image data

so that the image has an acceptable brightness level in

the presence of underexposure and overexposure. The

exposure error remains regardless of what occurs dur-

ing imaging processing. Underexposure appears on the

digital image as quantum noise/mottle that is clearly

visible in the thicker portions of the anatomy contained

in the image. Overexposure results in a loss of image

contrast throughout the image because of the increase

in radiation striking the image receptor. In the event of

significant overexposure, the result is the radiologist’s

inability to see all anatomical structures normally vis-

ible in the image because of saturation. The saturation

can be seen regardless of image brightness and contrast

settings. It is up to the radiographer and radiologist to

determine whether an underexposed or overexposed

image is of diagnostic quality.

Exposure Indicator

Digital systems lack the visual cues that lead to the

recognition of exposure errors when working with film-

screen imaging systems. As a result, the radiographer

needs to monitor the exposure indicator (EI) associated

with the digital imaging system. Monitoring the EI for

each image helps to track and eliminate trends that can

lead to dose creep. Radiographers should assess EIs as

part of image critique, keeping in mind the variability

among vendors and the limitations of the EI.

Exposure indicators have been developed by most

equipment manufacturers. The purpose of the EI is to

allow the radiographer to assess the level of exposure

the receptor has received and thereby determine if the

correct exposure technique for the image was used.

At the present time, the name of the EI varies widely

among manufacturers. In addition to the variations in

name between manufacturers, the relationship between

a change in the level of exposure and the corresponding

change in EI is anything but uniform among manufac-

turers. The lack of a standardized name and response

relationship between dose and exposure indicator cre-

ates confusion for radiographers who work with equip-

ment from multiple manufacturers, or of different ages

from the same manufacturer. It is critical to note that

EIs are not measures of radiation dose to the patient

and reiterate that EI records the level of exposure to the

image receptor.

The vendor community has responded, and by

a joint effort of the International Electrotechnical

Commission, the Medical Imaging and Technology

Alliance (MITA) and the American Association of

Physicists in Medicine (AAPM), manufacturers are

implementing an international standard for EIs called

IEC 62494-1. The IEC standard provides common

EI values for use with all types of digital image recep-

tors. The standard EI values do not provide an actual

patient dose, but instead provide an estimated value of

the incident radiation exposure to the detector for each

acquired image.

In 2009, the AAPM published AAPM Report 116:

An Exposure Indicator for Digital Radiography. The

report contains multiple recommendations regarding

the standardization of an exposure indicator. The rec-

ommendations of greatest significance to the radiogra-

pher are the use of consistent terminology among man-

ufacturers; a uniform response relationship between

receptor exposure and exposure indicator; identifica-

tion of target exposure values for examinations and a

clinically relevant exposure level indicator. Another of

the many recommendations contained in the report is

that each technologist workstation include a prominent

display of the DI following each image.

The deviation index (DI) is an important term to

recognize and understand. The deviation index is

based upon the established target exposure index val-

ues for the examination. The purpose of the deviation

index is to provide the radiographer with feedback

related to the level of exposure used to create the

image and to aid in determining whether corrective

action is required.

As a best practice in digital radiography,

radiographers must become familiar with the

specific EI standards for their equipment, and with

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the newer standardized EI and DI as they become

available in new and upgraded equipment used for

digital radiography.

Exposure Indicator Limitations

It is important to remember that currently the EI is

an indication of incident exposure at the image receptor

and not the radiation dose to the patient. A radiogra-

pher must understand the exposure technique factors

that lead to the EI value. During the processing of the

image data, a portion of the sequence involves the

identification of exposure field borders. Errors during

exposure field recognition can cause inaccurate stan-

dard deviation readings, and causes of exposure field

recognition errors vary among vendors.

Other limitations are the varying methods that

manufacturers use to determine relevant image regions

to analyze when generating EI values. Further, the

wide exposure range afforded by digital imaging and

issues such as poor collimation, patient positioning or

a patient’s unusual body habitus can cause EIs to be

higher or lower than expected. Completing an exami-

nation with an acceptable EI should not automatically

be accepted as verification of proper technique. A best

practice in digital radiography is the effective use of

the EI to determine whether adequate exposure has

reached the image receptor. The EI provides valuable

information about exposure to the image receptor,

and when evaluated along with image quality, assists

the radiographer in determining whether the digital

image meets departmental standards. Because the

EI has limitations, the radiographer must carefully

assess whether a repeat exam is necessary.

Artifact Analysis

Artifacts are unwanted densities in the image that

are not part of the patient’s anatomy and may nega-

tively affect the diagnostic quality of the image. The

classification of artifacts with film-screen imaging are

based upon how and when the artifact is recorded on

the image. Radiographers are accustomed to identify-

ing artifacts in film-screen radiographs, along with

their causes. Artifacts are classified according to cause:

exposure, processing and handling/storage. Artifacts

on digital images also can be classified into exposure,

processing and handling/storage. Regardless of the

acquisition method, radiographers should determine

the cause of any artifact on a digital image and report it

according to departmental policy.

Storage Phosphor Artifacts

Storage phosphor based image receptors used in CR

may be cassette-based or cassette-less. Because of the

manner in which the image data is captured and sub-

sequently processed, storage phosphor based receptors

present artifacts that are unique to their design. The

phosphor plate may be the source of the artifact. Dust,

stains, cracks and scratches are some of the causes of

artifacts in the image. Identifying plate artifacts is a

straightforward process because the artifact only occurs

with one particular plate. Removing the damaged

plate or cleaning the dirty plate corrects the problem.

Cleaning of the phosphor plate should be done in accor-

dance with the manufacturer’s directions.

When artifacts occur routinely across multiple exam-

inations, they most likely are caused by problems that

occur during the reading of the plate. A description of

the components of the plate reader is beyond the scope

of this paper. However, a few key components that often

are involved with artifacts that occur at the time of plate

processing are the light guide, mirror optics, laser sys-

tem and plate transport mechanism. Determining the

source of a plate reader artifact can be challenging. The

artifact needs to be described in terms of its brightness,

size, shape and location on the image.

Another source of image artifacts that occur across

multiple examinations involves the electronic and soft-

ware components associated with the image creation.

Identifying the specific source of this type of artifact is

particularly difficult because of the frequency of their

occurrence and the complexity of the electronic cir-

cuitry. The appearance of these types of artifacts also

should be described in terms of their brightness, size,

shape and location on the image.

Finally, some CR image artifacts are caused by prob-

lems with the hardcopy printer; these closely resemble

film-screen artifacts. Fog, pressure marks and static

electricity can appear on printed images. Image dis-

tortion, abnormal shading and uneven distribution of

line scans can occur when the printer’s film conveyor

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Best Practices in Digital Radiography

system malfunctions. Radiographers also can cause

artifacts on the printed CR image if they place single-

emulsion film upside down in the printer.

Direct Digital Receptor Artifacts

The flat-panel TFT and CCD-based receptors are

highly integrated and use complex electronic systems.

The flat-panel TFT receptors may be cassette-based

or cassette-less. At the time of this writing, the CCD-

based receptor is cassette-less. The appearance of

artifacts on these systems is described in terms of their

brightness, size, shape and location on the image. The

appearance of an artifact with direct digital systems can

be the loss of an individual pixel within the image or the

loss of rows or columns of pixels. In addition, system

calibration issues can affect the entire image, resulting

in an image that does not have the proper brightness

and gray scale. Correction of the artifacts associated

with direct digital systems may occur by using a built-in

calibration software or may require contacting service

personnel to repair the equipment.

Image Processing Software Artifacts

Digital systems have elaborate software that is used

to process the image data to produce a specific image

appearance. The radiographer’s selection of the process-

ing menu (specific to the body part and examination)

is a critical step during the imaging process that helps

minimize the likelihood of image processing artifacts.

Each examination menu has associated computer

analysis codes that are specific to the examination and

designed to determine the image appearance.

On some systems, the processing menu also deter-

mines how the EI is calculated for that examination. It is

because of this specificity that the radiographer needs to

select the appropriate processing menu to avoid process-

ing artifacts and miscalculation of EIs. The selection of

the processing menu affects the display qualities of the

image, and in some systems menu selection can affect

the spatial resolution of the image. The common display

qualities of the image that menu selection can control

are brightness, contrast, edge enhancement and equal-

ization. The specifics of how each of these display char-

acteristics is manipulated are beyond the scope of this

paper. In the circumstance that a selected processing

menu does not produce the desired image appearance,

the radiographer needs to determine whether how the

exam was performed caused the poor quality image or

whether the menu needs correction. The menu should

only be corrected by someone with a thorough under-

standing of image processing as it applies to the specific

piece of equipment. It is important to note that when

used inappropriately, edge enhancement and equaliza-

tion can degrade the diagnostic quality of the image sub-

mitted to PACS and therefore potentially affect the final

image interpretation.

A best practice in digital radiography is to recog-

nize image artifacts and prevent future artifacts from

occurring by properly maintaining or acquiring ser-

vice for the digital radiography equipment. In addi-

tion, a best practice in digital radiography is selection

of the correct processing menu for an examination to

ensure image quality.

Medical-legal Considerations

The radiographer must review the image from a

medical-legal standpoint, taking into consideration

such indications as ensuring that lead markers were

used and are visible on the digital image, and that

patient name and date of exam are imbedded in the

image. All departments should have documented

policies and procedures regarding digital imaging.

Radiographers should adhere to these policies and

should document sound reasons for deviations from

these policies and procedures for a given examina-

tion. Radiographers must review the image not only

for adequate exposure technique and image quality

with radiation safety in mind, but also for medical-

legal implications.

Following Examination Completion

It is helpful for radiographers to remember that

image acquisition, processing and display are separate

stages in digital imaging. As a result, images can be

evaluated and optimized throughout each stage. As a

best practice, however, radiographers should resist the

urge to modify image features after images have been

processed and displayed. There are steps radiogra-

phers should take after the examination is completed,

though, to ensure that data associated with the image

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Best Practices in Digital Radiography

(dose and demographics) are recorded and that the

final image is prepared for diagnostic interpretation.

Postprocessing

Digital imaging offers postprocessing capabilities

that are not possible with film-screen radiography.

Regardless, radiographers should perform postprocess-

ing of digital images only if necessary. Any electronic

masking that the radiographer performs on the image

should take place only outside of the actual exposure

field, and not be confused with collimation during the

image acquisition stage.

The digital image has original, raw data that should

be kept intact. Postprocessing can change the original

raw data and the set point that establishes the levels of

gray scale assigned to the pixels. A change in the raw

data can cause loss of information and thereby affect

the viewing capabilities in the PACS where it will be

accessed by the radiologist or referring physician for

diagnosis. Therefore, radiographers should adjust

window level or width settings only if absolutely nec-

essary. As described in the previous section on image

processing software artifacts, if radiographers find that

the processing menu chosen does not provide adequate

image quality, they should identify the cause of the

poor image quality and determine appropriate correc-

tive action. The processing menus are designed to pro-

vide optimum image quality relative to the anatomical

part exposed to x-rays. If the processing menu consis-

tently provides inadequate image quality, the radiogra-

pher should report the problem for adjustment.

Recording of Exposure and Dose Data

All EI and exposure technique information (such

as mAs and kVp) should be included with the digital

image. All exposure information should be displayed

for the radiographer upon image review, and should

be retained as part of digital imaging and communica-

tions in medicine (DICOM) information imbedded

in the DICOM header. In digital radiography systems

where the x-ray control panel is not connected to

the image receptor electronically, such as with many

cassette-based systems, the radiographer should record

the technical factor information in the electronic data

associated with the image.

It is best practice that all radiation exposure infor-

mation be recorded without radiographer interven-

tion to eliminate errors or incomplete records, and

international standards have been issued to ensure

this occurs. The standards may not apply, however,

to all types and brands of equipment, particularly

cassette-based systems. Radiology departments

should work closely with vendors and PACS admin-

istrators to determine how EIs and technique factors

can be recorded according to departmental policy and

attached to and transmitted with the image. Currently,

radiographers can add missing information only in

technologist notes.

Inclusion of exposure information on every final

digital radiograph will help radiographers to take note

of and use the information for refinement of exposure

technique selection. Inclusion of data related to tech-

nical factors on every final exam’s DICOM header

should ensure that the radiology department can

maintain quality and adherence to the ALARA con-

cept. It is essential that EI values and exposure tech-

nique factors be recorded and tracked along with dose

information. It is a best practice in digital radiogra-

phy to electronically record exposure technique, EI

and dose data with the radiographic image to allow

for assessment and refinement of technique selec-

tion practices.

Quality Assurance

The need for sound quality control (QC) practices

as part of a quality management program is important

in digital imaging. Radiographers are the operators

of complex imaging equipment and therefore are

the individuals who may first recognize equipment

malfunction. In addition, as with film-screen radiog-

raphy, human error can occur with digital imaging,

and these errors must be acknowledged and corrected

to prevent trends that could jeopardize patient radia-

tion safety. Even more important, problems that

occur in digital acquisition or processing equipment

tend to be systematic problems, which can affect the

quality of every image and the radiation exposure of

every patient until the problems are identified and

corrected. Acceptance testing, regular calibration

and proactive and consistent QC can prevent these

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Best Practices in Digital Radiography

systematic errors; repeat analyses can contribute to

overall department quality improvement.

Equipment Acceptance Testing and Calibration

Digital equipment is calibrated at the manufac-

turer’s site, but conditions change when the equipment

is installed on site. A sound QC program begins with

thorough and organized acceptance testing imme-

diately following equipment installation and before

clinical use. The facility’s medical physicist should be

actively involved in the acceptance testing, following

the most current AAPM task force recommendations

for establishing standards of performance for digital

equipment. Initial testing and equipment calibration

often is followed by a period of observation while the

device undergoes routine use. Initial acceptance testing

and calibration also helps the physicist establish a base-

line performance for the equipment and subsequent

QC testing, which should occur systematically to rees-

tablish a baseline.

Systematic Quality Control

Generators and x-ray tubes generally remain the

same when converting to digital systems, but other

parts of digital systems are new to radiographers

and require updated QC policies and procedures.

Departments transitioning to digital may have to

revise their QC procedures to accommodate digital

imaging. Regular performance testing and calibra-

tion of equipment should be done in accordance with

equipment manufacturer specifications, industry stan-

dards and any applicable state and federal regulations.

ACR guidelines recommend that a medical physicist

assist in establishing the systematic QC program,

monitor results and assist with corrective actions. In

addition, radiographers must become familiar with

the performance operation of the equipment in an

effort to identify potential equipment malfunction and

report their concerns to the appropriate individuals.

The guidelines also recommend that an on-site

radiographer be responsible for conducting routine

QC noninvasive activities. Radiographers should per-

form daily and periodic checks of equipment that do

not require physicist involvement. For example, the

radiographer should inspect the digital system daily

for possible physical defects, perform weekly phantom

testing for image quality and artifacts, and inspect

and clean image receptors routinely. It may not be

possible to perform every QC test daily, but periodic

testing can identify potential equipment malfunction.

Examples follow below, but each department may

vary, depending on the established quality assurance

program, along with institutional, state and federal

regulations or accrediting standards.

Image Receptors

QC procedures on image receptors may vary

depending on the type of digital imaging equipment

and manufacturer. It is important for the radiographer

to follow the manufacturer’s recommendations and

recognize performance malfunctions. At a minimum,

radiographers should perform routine equipment self-

tests and calibration procedures where appropriate

or image a QC phantom to assess equipment perfor-

mance on a regular basis. In addition, CR imaging

plates should be visually inspected for damage or arti-

facts and cleaned appropriately. Radiographers also

should perform secondary erasure of plates daily at the

start of their shifts to prevent exposure artifacts.

Display Monitor

Display monitor performance has taken on added

importance because digital images only are viewed

electronically for quality review and diagnostic inter-

pretation. Though most QC activities for monitors

are not the responsibility of radiographers, it is help-

ful to understand the basics of monitor performance.

Radiologists’ display monitors used for interpretation

(primary) should be tested and monitored according

to specifications set forth by the manufacturers and

the ACR Quality Control Manual, along with appli-

cable state and federal regulations. Devices degrade at

different rates, but generally should be tested at least

monthly, and more frequently as they become older.

There are more stringent guidelines in place for diag-

nostic monitors than for secondary display monitors,

which are found at the radiographer workstations. It

is important that monitors throughout a work area be

consistent in terms of spatial resolution, luminance

(the amount of light emitted) and contrast resolution.

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Best Practices in Digital Radiography

Radiographers should physically inspect their

digital workstation monitors daily. Physicists use

Society for Motion Picture and Television Engineers

(SMPTE) or AAPM test patterns as minimum QC

checks for display monitors as well. A QC test pattern

should be imaged and displayed to test normal opera-

tion and stored to compare results over time.

Repeat Analysis

A repeat analysis should be a component of any qual-

ity assurance program in radiology. The monitoring of

repeats allows for the assessment of overall image qual-

ity, modification of examination protocols, the need for

in-service education, and tracking of patient radiation

exposures. Radiographers need to accurately identify

and document the reason for a repeat image. Analysis of

the department’s repeat rate provides valuable informa-

tion for process improvement and the overall perfor-

mance of the radiology department, and helps minimize

patient radiation exposure.

It is a best practice in digital radiography to imple-

ment a comprehensive quality assurance program

that involves aspects of quality control and continu-

ous quality improvement, including repeat analyses

that are specific to the digital imaging system.

Workplace Culture

When departments convert to digital environ-

ments, the effects are felt beyond the demands of

learning to operate new equipment. Digital imaging

affects workflow within and outside of the radiol-

ogy department. Although numerous personnel

must adjust, the implementation of digital radiogra-

phy affects radiographers more than any other staff

members. The electronic transmission of images

from radiographer to radiologist and other workflow

issues have significantly reduced the amount of direct

contact between the radiographer and the radiolo-

gist, thereby affecting their working relationship.

Radiographers have less opportunity to discuss image

quality or other issues with the radiologist. Only

teamwork and open efforts at communication can

ensure a smooth transition and an ongoing culture

of quality, safety and efficiency. It is up to radiog-

raphers to personally emphasize a culture of safety

and professionalism and to pursue open discussions

regarding digital radiography to learn from and sup-

port radiologists and other technologists.

Safety and Professionalism

Digital radiography is expected to improve workflow

and patient throughput. As a result, radiographers often

are expected to work faster or manage more patients. It

is critical that radiographers continue to adhere to pro-

tocols and retain their responsibilities for patients even

in this fast-paced environment. The potential for harm

in performing radiologic examinations is high. A cul-

ture of safety and professionalism emphasizes patient

safety and advocacy, and recognizes the radiographer’s

critical role as the professional who delivers radia-

tion to patients. The American Registry of Radiologic

Technologists (ARRT) Code of Ethics and ASRT

Practice Standards for Medical Imaging and Radiation

Therapy both emphasize professionalism and radiogra-

phers’ participation in and adherence to patient safety

activities. The ASRT Practice Standards also emphasize

innovation and lifelong learning.

It is essential that radiographers continue to learn

in an industry with technological advancements as the

norm. Radiographers should learn from one another as

well as from vendors, supervisors, physicians and formal

education or continuing education programs. Most

of all, a culture of safety and professionalism recog-

nizes improvement and modification of systems and

operations over punishment of individuals. Successful

safety cultures are proactive, working to prevent error

events. Prevention of errors requires transparent

reporting without fear of reprisal and with the intent

of continuous improvement. Thus, a strong teamwork

environment is imperative.

Promote Collaboration and Radiation Safety in the

Workplace

The culture of safety and improvement must take

place within a fluid workforce. This can be positive

if members approach it professionally and as a team.

For example, ARRT data show that by 2015, the age

of radiologic technologists in the workplace will “bal-

ance,” and workers from the baby boom, generation

X and generation Y demographics will each make up

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Best Practices in Digital Radiography

about one-third of the workforce. In a 2011 ASRT

workplace survey of hospital-based radiologic tech-

nologists, 11 percent of registered radiologic technolo-

gists said they had left the radiologic sciences field.

Of those 11 percent, nearly 26 percent said they left

because they retired.

Most recent graduates have been educated using

digital radiography, and can contribute to the under-

standing of practicing radiographers regarding the

technology and workflow. To do so, however, experi-

enced radiographers must be open to the recent gradu-

ates’ input. On the other hand, recent graduates must

appreciate and respect the backgrounds and practical

knowledge of experienced technologists.

Donnelly et al implemented a comprehensive

approach to patient safety in a radiology department

that included teamwork with other hospital depart-

ments, addressing staffing, opening communication

and feedback mechanisms, teamwork, nonpunitive

error responses and support from supervisors and

hospital management for patient safety. The number

of days between serious safety events increased nearly

fourfold. Emphasizing teamwork and implementing

formal safety programs can shift the culture toward

one focused on overall patient safety instead of simply

reporting errors or concerns about exposure alone.

A best practice in digital radiography is the devel-

opment of a collaborative and supportive work team

in which team members learn from one another and

practice radiography safely and ethically.

Applications Training and Support

The ACR guideline for digital imaging recommends

that radiographers performing digital examinations be

trained to properly operate the systems they routinely

use. The training should include image acquisition

technology, image processing protocols, proper selec-

tion of protocol options for specific examinations,

image review, EIs and radiation safety during proce-

dures. Though it is appropriate for radiographers and

their supervisors to rely on applications training to sup-

ply equipment-specific training in these skills, it is the

responsibility of the radiographer to have base knowl-

edge regarding digital radiography while using radiation

exposure techniques and ALARA principles designed

to minimize patient radiation exposure.

The ASRT Practice Standards state that radiogra-

phers should be educationally prepared and clinically

competent to perform their jobs. Education and clinical

preparation include being prepared to perform digital

examinations should their departments use the tech-

nology. Managers should support these efforts, but it

is the responsibility of radiographers to take advantage

of the literature, seminars and other educational tools

available to them to become clinically competent. The

radiographer must retain all skills necessary for per-

forming examinations and work cooperatively with

radiologists to reduce radiation exposure.

The variation in vendor-specific features necessitates

thorough and ongoing applications training for digital

equipment. Radiology departments and radiographers

should be proactive in seeking help from vendors, par-

ticularly during equipment installations and upgrades to

provide appropriate training; however, vendors also must

ensure that their applications specialists and support per-

sonnel are continuously trained and updated on changes

to technology. Vendors and radiology department man-

agers must work together to determine training expec-

tations in advance, which includes preassessment and

postassessment of trainees’ skills and time expectations.

Once applications trainers arrive on site, managers must

support radiographers’ attendance at training, and train-

ees must remain engaged throughout training comple-

tion. It also is essential that all members of the digital

imaging team, including service engineers, have training

and updated competencies in radiation protection.

Review of Best Practices

The following best practices for digital radiography

have been identified in this paper. This is not an all-

inclusive list but one that highlights the actions most

pertinent to digital radiography, radiation safety and

ethical practice.

It is best practice to:

Select the appropriate exposure technique factors

for the patient’s size and condition, based on a

planned exposure system, designed in collabora-

tion with radiologists, to determine adequate

image quality for diagnosis.

Consistently include information regarding

the image receptor exposure in the image data

provided throughout the image archiving process.

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Best Practices in Digital Radiography

Carefully review the examination ordered to

prevent potential duplication and to ensure

appropriateness as related to the patient’s his-

tory. If there is a possibility that the examination

might be inappropriate, the radiographer then

should consult with the radiologist and/or order-

ing physician to ensure the appropriate examina-

tion is being obtained.

Follow the protocols and standards set by

the department and actively participate in

establishing and further developing protocols

that ensure consistency of diagnostic-quality

images and improved practices to reduce patient

radiation dose. This is a critical best practice in

digital radiography.

Screen patients for potential pregnancy.

Use the highest kVp within the optimal range

for the position and part coupled with the lowest

amount of mAs as needed to provide an adequate

exposure to the image receptor.

Use automatic exposure control (AEC) when

indicated and use AEC that has been calibrated to

the type of image receptor to provide a consistent

exposure to the image receptor.

Use exposure technique charts that are continu-

ously improved and applicable to a wide range of

patient ages and sizes.

Collimate the x-ray beam to the anatomic area

appropriate for the procedure.

Apply electronic masking in a manner that dem-

onstrates the actual exposure field edge to docu-

ment appropriate collimation.

Electronic masking must not be applied over

anatomy that was contained in the exposure field

at the time of image acquisition.

Use lead shielding for anatomic parts that are

adjacent to the x-ray field.

Consistently use lead anatomic side markers

captured on the original image during the x-ray

exposure.

Use a grid with specifications recommended by

the digital imaging equipment vendor, generally

for body parts that exceed 10 cm.

Use immobilization devices when needed and

prevent repeat exposures by appropriately posi-

tioning the patient.

Take appropriate actions to follow ALARA prin-

ciples, radiation protection, proper positioning,

immobilization and size-appropriate exposure

techniques in pediatric digital radiography.

Become familiar with the specific exposure indi-

cator standards for equipment and with the stan-

dardized EI as it becomes available in new and

upgraded equipment used for digital radiography.

Effectively use the EI and deviation index to

determine whether adequate exposure has

reached the image receptor.

Evaluate EI values, along with image quality

to determine whether the digital image meets

departmental standards.

Recognize that because the EI has limitations

and other variables can affect the value, carefully

assess whether a repeat examination is necessary.

Recognize image artifacts and prevent future

artifacts from occurring by properly maintaining

or acquiring service for the digital radiography

equipment.

Select the correct processing menu for an exami-

nation to ensure image quality.

Electronically record exposure techniques, EI

and dose data with the radiographic image to

allow for assessment and refinement of technique

selection practices.

Implement a comprehensive quality assurance

program that involves aspects of quality control

and continuous quality improvement, including

repeat analyses that are specific to the digital

imaging system.

Develop a collaborative and supportive work team

in which team members learn from one another

and practice radiography safely and ethically.

Recommendations

This committee makes several recommendations

for the future of digital radiography based on best prac-

tices to help ensure continued quality and improved

patient safety:

Industry societies and vendors must continue

to work together to improve standardization

of exposure indicator values. This includes

consistency in exposure indicators and standard

deviation indexes.

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Best Practices in Digital Radiography

Equipment manufacturers should provide

radiographers access to EI and DI information

clearly displayed on each image when viewed and

retained as part of the PACS DICOM headers to

ensure accurate exposures and data recording.

At the institutional level, all radiology depart-

ments should develop and post exposure tech-

nique charts with radiologist and radiologic tech-

nologist involvement; the charts must identify

acceptable exposure indicator ranges.

Members of the radiology team must collaborate

to promote patient radiation safety. This includes

medical physicists, radiologists, radiologic tech-

nologists and radiographers just graduating from

programs who have a more formal education

involving digital imaging skills.

Radiographers, equipment manufacturers and

physicists should investigate and perform research

into grid construction as appropriate for digital

imaging.

Radiographers, equipment manufacturers and

physicists should investigate and perform research

to further investigate kVp effects on patient dose

and the use of 15 percent increases (the 15 per-

cent rule) in digital radiography image receptor

systems.

Ensure that managers, radiologic technologists

and applications trainers collaborate to prepare

for applications training and base knowledge

before training begins on digital equipment.

Institutions that care for children must develop

radiologic and digital imaging equipment proto-

cols for pediatric radiography.

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Best Practices in Digital Radiography

Glossary

Bit depth. The number of bits, or binary digits, per

pixel. They encode the signal intensity (gray scale) of

each pixel for the digital image.

Collective dose. A measure of the total amount of

effective dose multiplied by the size of the exposed

population. Usually measured in units of person-rem or

person-sievert, or man-rem or man-sievert.

Computed radiography (CR). The imaging system,

most often cassette-based, that requires the cassette to

be manually inserted into a plate reader. CR uses pho-

tostimulable phosphor technology to capture images

that are then scanned by a laser to release the energy

absorbed, which is then to produce digital data that are

converted to an image.

Contrast resolution: also known as gray-scale reso-

lution. This is a digital system’s ability to display objects

at different signal (x-ray) intensities so that they can be

easily distinguished.

DICOM. Digital Imaging and Communications in

Medicine. DICOM is a standard developed to intercon-

nect medical digital imaging devices. The standard is

sponsored by the ACR and NEMA and aims to have

both a standard image file format and a standard com-

munications protocol.

Digital radiography. Any form of radiography in

which the acquisition and display of the image are elec-

tronic in nature; the imaging system may be cassette-

based or cassette-less This may include CR or DR as

defined in this glossary.

Direct digital radiography (DR). The imaging sys-

tem may be cassette-based or cassette-less. DR may use

a flat- panel with thin-film transistor or a charge-cou-

pled device. The image reading process occurs immedi-

ately after the termination of the exposure and does not

require the radiographer to initiate the reading process.

Effective dose. Effective dose is the quantity that

relates more closely to stochastic radiation risk. The

effective dose totals the absorbed dose to tissues and

the weighting factors that apply to particular tissues or

organs being irradiated.

Exposure indicator (EI). A quantitative method,

expressed as an EI value, to estimate the incident radia-

tion exposure required to acquire a diagnostic-quality

radiograph. The EI is called by many other names,

depending on the vendor.

Gray scale. The different shades of gray that a com-

puter system can store and display in relation to the

number of bits the system uses to digitize images.

Luminance. The measure that describes the amount

of light that passes through or is emitted from a surface.

In DR, this is the display monitor.

Pixel. A picture element, or the smallest component

of a digital image and piece of information that a digital

monitor can display. Pixels are represented by numeri-

cal codes.

Spatial resolution. Spatial resolution is the ability to

differentiate between small and adjacent objects. It is

measured in line pairs per millimeter (lp/mm).

Standard deviation index (DI). An index that pro-

vides feedback based on signal-to-noise ratio and the

target index value for each digital examination. The

purpose of the index is to help radiographers know

if the technique they used for a specific examination

was appropriate for optimal display of the anatomy of

interest.

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Best Practices in Digital Radiography

Exposure Indicators

Exposure indicators (EIs) vary among manufacturers, and even have different names, symbols and units. This chart

shows a list of select manufacturers and details regarding their EIs as of 2011.

Manufacturer EI Name EI Symbol Units Exposure Dependence Detector Calibration

Conditions

Agfa Log of median of

histogram

1gM Bels 1gM + 0.3 = 2X 400 speed class, 75 kVp + 1.5

mm Cu; 1gN = 1.96 @ 2.5 µGy

Alara CR Exposure indicator

value

EIV Mbels EIV + 300 = 2X 1 mR @ RQA5, 70 kV, +21 mm

A1 => EIV=2000

Canon Reached exposure

value

REX Unitless for brightess=c1, contrast=c2,

REX α X (mR)1

brightness = 16, contrast = 10,

1 mR = 1061

Canon EXP EXP Unitless EXP = X 80 kVp, 26 mm

A1, HVL=8.2 mm

A1, DFEI=1.5

Carestream

(formerly Kodak)

Exposure index EI Mbels EI + 300=2X 80 kVp. 1. 0 mm

A1 + 0.5 mm Cu; EI=2000 @

1mR

Fujifilm S value SUnitless 200/S X (mR) 80 kVp, 3 mm

A1 “total filtration”

S=200 @ 1 mR

GE Uncompensated

detector exposure

UDExp µGy air

kerma

UDExp α X (µ Gy) 80 kVp, standard filtration, no

grid

GE Compensated

detector exposure

CDExp µGy air

kerma

CDExp α X (µ Gy) kVp, grid, and additional filter

compensation

GE Detector exposure

index

DEI Unitless DEI≈ratio of actual exposure

to expected exposure scaled

by technique, system param-

eters. Expected exposure can

be edited by user.

Not available.

Konica Sensitivity number SUnitless for QR=k, 200/S α X(mR) For QR=200, 80 kVp, S=200 @

1 mR

Philips Exposure index EI Unitless 1000/X (µ Gy) RQA5, 70 kV + 0.6 mm Cu,

HVL=7.1 mm A1

Siemens Exposure index EI µ Gy air

kerma

X(µ Gy)=EI/100 RQA5, 70 kV+0.6 mm Cu,

HVL=6.8 mm A1

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Best Practices in Digital Radiography

Task Force Members

Tracy Herrmann, M.Ed, R.T.(R), University of Cincinnati, Blue Ash College, Professor and Radiologic

Technology Program Director

Terri L. Fauber, Ed.D., R.T.(R)(M), Virginia Commonwealth University, Radiography Program Director

Julie Gill, Ph.D., R.T.(R)(QM), University of Cincinnati, Blue Ash College, Chairperson and Associate

Professor, Allied Health

Colleen Hoffman, R.T.(R)(M)(CT), Atlantic Medical Imaging, PACS Administrator

Denise Orth, M.S., R.T.(R)(M), Fort Hays State University, Assistant Professor/Clinical Coordinator

Paulette Peterson, M.Ed, R.T.(R)(M)(QM), Monroe Community College, Associate Professor/Clinical

Coordinator

Randy Prouty, B.S., R.T.(R), Regional West Medical Center, Diagnostic Supervisor

Andrew Woodward, M.A., R.T.(R)(CT)(QM), The University of North Carolina at Chapel Hill, Assistant

Professor

Best Practices In Digital Radiography Asrt12 Bstpracdigradwhp

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