The American College of Radiology, with more than 30,000 members, is the principal organization of radiologists, radiation oncologists,

and clinical
medical physicists in the United States. The College is a nonprofit professional society whose primary purposes are to advance the science of radiology,
improve radiologic services to the patient, study the socioeconomic aspects of the practice of radiology, and encourage continuing education for
radiologists, radiation oncologists, medical physicists, and persons practicing in allied professional fields.

The American College of Radiology will periodically define new practice parameters and technical standards for radiologic practice to help advance the
science of radiology and to improve the quality of service to patients throughout the United States. Existing practice parameters and technical standards
will be reviewed for revision or renewal, as appropriate, on their fifth anniversary or sooner, if indicated.

Each practice parameter and technical standard, representing a policy statement by the College, has undergone a thorough consensus process in which it has
been subjected to extensive review and approval. The practice parameters and technical standards recognize that the safe and effective use of diagnostic
and therapeutic radiology requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published
practice parameter and technical standard by those entities not providing these services is not authorized.

Revised 2018 (Resolution 9)*

ACR–SPR–SSR PRACTICE PARAMETER FOR THE PERFORMANCE OF

MUSCULOSKELETAL QUANTITATIVE COMPUTED TOMOGRAPHY (QCT)
PREAMBLE

This document is an educational tool designed to assist practitioners in providing appropriate radiologic care for
patients. Practice Parameters and Technical Standards are not inflexible rules or requirements of practice and are
not intended, nor should they be used, to establish a legal standard of care 1. For these reasons and those set forth
below, the American College of Radiology and our collaborating medical specialty societies caution against the
use of these documents in litigation in which the clinical decisions of a practitioner are called into question.
The ultimate judgment regarding the propriety of any specific procedure or course of action must be made by the
practitioner in light of all the circumstances presented. Thus, an approach that differs from the guidance in this
document, standing alone, does not necessarily imply that the approach was below the standard of care. To the
contrary, a conscientious practitioner may responsibly adopt a course of action different from that set forth in this
document when, in the reasonable judgment of the practitioner, such course of action is indicated by the condition
of the patient, limitations of available resources, or advances in knowledge or technology subsequent to
publication of this document. However, a practitioner who employs an approach substantially different from the
guidance in this document is advised to document in the patient record information sufficient to explain the
approach taken.
The practice of medicine involves not only the science, but also the art of dealing with the prevention, diagnosis,
alleviation, and treatment of disease. The variety and complexity of human conditions make it impossible to
always reach the most appropriate diagnosis or to predict with certainty a particular response to treatment.
Therefore, it should be recognized that adherence to the guidance in this document will not assure an accurate
diagnosis or a successful outcome. All that should be expected is that the practitioner will follow a reasonable
course of action based on current knowledge, available resources, and the needs of the patient to deliver effective
and safe medical care. The sole purpose of this document is to assist practitioners in achieving this objective.

1 Iowa Medical Society and Iowa Society of Anesthesiologists v. Iowa Board of Nursing, ___ N.W.2d ___ (Iowa 2013) Iowa Supreme Court refuses to find
that the ACR Technical Standard for Management of the Use of Radiation in Fluoroscopic Procedures (Revised 2008) sets a national standard for who may
perform fluoroscopic procedures in light of the standard’s stated purpose that ACR standards are educational tools and not intended to establish a legal
standard of care. See also, Stanley v. McCarver, 63 P.3d 1076 (Ariz. App. 2003) where in a concurring opinion the Court stated that “published standards or
guidelines of specialty medical organizations are useful in determining the duty owed or the standard of care applicable in a given situation” even though
ACR standards themselves do not establish the standard of care.

PRACTICE PARAMETER 1 QCT

I. INTRODUCTION

This practice parameter was revised collaboratively by the American College of Radiology (ACR), the Society for
Pediatric Radiology (SPR), and the Society of Skeletal Radiology (SSR).

Musculoskeletal quantitative computed tomography (QCT) can be used to accurately and reproducibly measure
bone mass [1-12] or muscle mass [13-17]. QCT is a clinically proven method of measuring bone mineral density
(BMD) in the spine and proximal femur. QCT is used primarily in the diagnosis and management of osteoporosis
and other disease states that may be characterized by abnormal BMD, as well as to monitor response to therapy
for these conditions.

For BMD measurement, QCT has some advantages over dual-energy X-ray absorptiometry (DXA). DXA
measurements may be significantly biased by severe degenerative changes of the hip or spine, vascular
calcifications, oral contrast agents, and foods or dietary supplements containing significant quantities of calcium
or other heavier minerals or elements [18-20]. QCT is also accurate in patients with extremely high or low body
mass index [21-24].

There are well-documented differences in the response of cortical and trabecular bone to aging and therapeutic
interventions. QCT spine BMD measurements are used to characterize only trabecular bone, while hip area-
density measurements obtained using QCT predominantly characterize cortical bone. QCT spine BMD
measurements provide a sensitive indication of spine fracture risk and a somewhat less sensitive indication of hip
fracture risk [25,26].

For pediatric applications, see section II.B. It should be noted that peripheral QCT (pQCT) is commonly
performed in children. It has the advantage of lower radiation dose [27].

This practice parameter outlines the principles of performing high-quality musculoskeletal QCT.

II. INDICATIONS AND CONTRAINDICATIONS

Musculoskeletal QCT measurement is indicated whenever a clinical decision is likely to be directly influenced by
the result of the test. For measurement of BMD, QCT may be considered in place of or in addition to DXA in the
following circumstances [28-35]:

A. Indications for QCT include, but are not limited to, individuals with suspected abnormal bone or muscle mass
including:

1. All women 65 years and older and men 70 years and older (asymptomatic screening).
2. All postmenopausal women younger than 65 years and men younger than 70 years who have risk
factors for osteoporosis including:
a. A history of fracture; a wrist, hip, spine, or proximal humerus fracture with minimal or no trauma,
excluding pathologic fractures
b. Family history of osteoporotic fracture
c. Low body mass (less than 127 lbs or 57.6 kg)
d. Current use of cigarettes
e. Excessive use of alcohol
f. Loss of height, thoracic kyphosis
3. Individuals of any age with findings suggestive of demineralization [36] or fragility fractures on
imaging studies, such as radiographs, computed tomography (CT), or magnetic resonance imaging
(MRI) examinations.
4. Individuals receiving (or expected to receive) glucocorticoid therapy for more than 3 months.
5. Individuals beginning or receiving long-term therapy with medications known to adversely affect
BMD (eg, anticonvulsant drugs, androgen deprivation therapy, aromatase inhibitor therapy, or
chronic heparin).

PRACTICE PARAMETER 2 QCT

 6. Individuals with an endocrine disorder known to adversely affect BMD (eg, hyperparathyroidism,
hyperthyroidism, or Cushing’s syndrome).
7. Postpubertal hypogonadal males with surgically or chemotherapeutically induced castration [37,38].
8. Individuals with medical conditions associated with abnormal BMD, such as:
a. Chronic renal failure
b. Rheumatoid arthritis and other inflammatory arthritides
c. Eating disorders, including anorexia nervosa and bulimia
d. Gastrointestinal malabsorption or sprue
e. Osteomalacia
f. Acromegaly
g. Chronic alcoholism or established cirrhosis
h. Multiple myeloma
i. Gastric bypass surgery
j. Organ transplantation
k. Prolonged immobilization
9. Individuals being monitored to:
a. Assess the effectiveness of osteoporosis drug therapy [39-41]
b. Follow-up medical conditions associated with abnormal BMD
10. Individuals with extremely high obesity or low body mass index, in whom DXA measurements of
BMD may not be accurate.
11. QCT of muscle may be indicated as a tool to measure sarcopenia (eg, for patients with cancer) [42].

B. Pediatric Indications and Considerations

Indications for performing BMD examinations and its subsequent assessment in children differ significantly from
those in adults. Interpreting BMD measurements in children is complicated by the growing skeleton [43,44].
DXA is unable to take into account changes in body and skeletal size during growth, limiting its usefulness in
longitudinal studies. For example, an increase in DXA-measured areal BMD in the spine is more likely a
reflection of change of vertebral size than a change in BMD [45]. Because QCT can assess both volume and
density of bone in the axial and appendicular skeleton, it may be more useful than DXA in children [46]. Due to
its lower radiation dose, pQCT, which assesses the extremities, may be preferable to central QCT in pediatric
patients.

In children and adolescents, BMD measurement is indicated whenever a clinical decision is likely to be directly
influenced by the result of the test. Indications for QCT/pQCT include, but are not limited to [47]:

1. Individuals receiving (or expected to receive) glucocorticoid therapy for more than 3 months.
2. Individuals receiving radiation or chemotherapy for malignancies.
3. Individuals with an endocrine disorder known to adversely affect BMD (eg, hyperparathyroidism,
hyperthyroidism, growth hormone deficiency or Cushing’s syndrome).
4. Individuals with bone dysplasias known to have excessive fracture risk (osteogenesis imperfecta,
osteopetrosis) or high BMD, such as prolonged exposure to fluoride
5. Individuals with medical conditions that could alter BMD, such as:
a. Chronic renal failure
b. Rheumatoid arthritis and other inflammatory arthritides
c. Eating disorders, including anorexia nervosa and bulimia
d. Organ transplantation
e. Prolonged immobilization
f. Sprue, inflammatory bowel disease, malnutrition
g. Cystic fibrosis
h. Osteomalacia
i. Acromegaly
j. Cirrhosis
k. HIV infection, prolonged exposure to fluorides
l. Hematologic disorders (Thalassemia, Sickle cell disease)

PRACTICE PARAMETER 3 QCT

C. Contraindications
1. There are no absolute contraindications to performing QCT. However, a QCT examination may be of
limited value or require modification of the technique or rescheduling of the examination in some
situations, including:
a. Administration of intravascular iodinated contrast. If a QCT of the spine and contrast enhanced
examination of the abdomen are performed simultaneously, the bone or muscle may be altered by the
contrast enhancement [48].
b. Pregnancy
c. Severe degenerative changes or fracture deformity in the measurement area
d. Implants, hardware, devices, or other foreign material in the measurement area
e. Inability to position the patient completely within the scanning field of view

2. For the pregnant or potentially pregnant patient, see the ACR–SPR Practice Parameter for Imaging
Pregnant or Potentially Pregnant Adolescents and Women with Ionizing Radiation [49].

III. QUALIFICATIONS AND RESPONSIBILITIES OF PERSONNEL

For the physician, medical physicist, and radiologic technologist qualifications, see the ACR Practice Parameter
for Performing and Interpreting Diagnostic Computed Tomography (CT) [50]. Additional specific qualifications
and responsibilities include:

A. Physician [51]

1. The examination must be performed under the supervision of and interpreted by a licensed physician with
the following qualifications:
a. Documented training in and understanding of the physics of X-ray absorption and radiation
protection, including the potential hazards of radiation exposure to both patients and personnel and
the monitoring requirements.
b. Knowledge and understanding of the process of QCT data and image acquisition, including proper
patient positioning and placement of regions of interest, and artifacts and anatomic abnormalities that
may falsely increase or decrease measured values.
c. Knowledge and understanding of the analysis and reporting of QCT, including, but not limited to:
BMD values, T-score, Z-score, and fracture risk.
d. Knowledge and understanding of the criteria for comparison of serial measurements, including
limitations of comparing measurements made by different techniques and different devices.
e. Knowledge and understanding of other bone densitometry techniques, including DXA, peripheral
DXA, pQCT, and quantitative ultrasound, to fulfill a consultative role in recommending further bone
densitometry studies, future serial measurements, or diagnostic procedures to confirm suspected
abnormalities seen on QCT images.

2. The supervising physician is responsible for overseeing the QCT facility and its equipment quality control
program. The physician accepts final responsibility for the quality of all QCT examinations.

B. Radiologic Technologist

1. The examination must be performed by a technologist with the following responsibilities and
qualifications:
a. Ensuring patient comfort and safety, preparing and properly positioning the patient, placing regions of
interest, monitoring the patient during the procedure, and obtaining the measurements prescribed by
the supervising physician.
b. Determining the precision error of the equipment (see section VII).
c. Documented formal training in the use of the QCT equipment, including performance of all
manufacturer-specified quality assurance (QA) procedures.

PRACTICE PARAMETER 4 QCT

 d. Knowledge of and familiarity with the manufacturer’s operator manual for the specific scanner model
being used.
e. State licensure and/or certification, if required.
f. Certification by the American Registry of Radiologic Technologists in CT is also desirable.

2. Continuing Medical Education

The technologist’s continuing medical education should be in accordance with the national registry or
state licensure requirements, where applicable.

IV. SPECIFICATIONS AND ANALYSIS OF THE EXAMINATION

A. The written or electronic request for a QCT examination should provide sufficient information to demonstrate
the medical necessity of the examination and allow for the proper performance and interpretation of the
examination.

Documentation that satisfies medical necessity includes 1) signs and symptoms and/or 2) relevant history
(including known diagnoses). The provision of additional information regarding the specific reason for the
examination or a provisional diagnosis would be helpful and may at times be needed to allow for the proper
performance and interpretation of the examination.

The request for the examination must be originated by a physician or other appropriately licensed health care
provider. The accompanying clinical information should be provided by a physician or other appropriately
licensed health care provider familiar with the patient’s clinical problem or question and consistent with the state
scope of practice requirements. (ACR Resolution 35, adopted in 2006 – revised in 2016, Resolution 12-b)

B. QCT

For BMD measurement, QCT may involve phantom-based or phantomless acquisition. Most commonly, adults
may have QCT of the spine and/or hip. Children usually have only a spine QCT or pQCT. Anatomic areas of
prior surgery or known fracture should be excluded from measurement.

1. Phantom-based QCT acquisition

a. Phantom-based QCT acquisition can be performed with simultaneous scanning patient and phantom
or with asynchronous scanning of patient and phantom:QCT has historically been performed with
simultaneous scanning of the patient and a calibration phantom. There are a number of different
techniques, with technical parameters dependent on manufacturer [52]. The QCT software uses
known phantom densities and measured CT attenuation to calculate BMD of the spine or hip. The
primary advantage of this technique is that any variation in CT scanner output is corrected for by the
simultaneous scan.
b. Asynchronous techniques allow for scanning of the calibration phantom at a different time from the
scanning patient. This is possible because of greater stability of x-ray output by modern CT scanners
[11,52,53]. The temporal decoupling of phantom and patient scanning allows more convenient
scanning because there is no need to use the phantom for each patient scan. In addition, BMD can be
calculated from CT examinations originally obtained for purposes other than BMD measurement
(opportunistic screening).

2. Phantomless QCT Acquisition

Various phantomless techniques for QCT are gaining in popularity [11,52]. All of these techniques have
the obvious benefit of not requiring a calibration phantom. One technique uses the patient’s muscle and
fat for calibration when calculating BMD [54]. Another technique estimates BMD by performing calcium
material decomposition using dual-energy CT acquisition [55]. Other phantomless techniques do not
attempt to measure BMD, but instead use the actual CT attenuation values to screen for osteoporosis [56].
This technique has broad appeal in that it can be easily performed by measuring the mean CT attenuation
on PACS viewers. However, CT attenuation of bone can vary significantly with varying CT parameters

PRACTICE PARAMETER 5 QCT

 such as kVp [57]. Like asynchronous techniques, phantomless techniques can be applied to CT
examinations originally obtained for purposes other than BMD measurement (opportunistic screening).

C. Diagnosis of osteoporosis

1. Hip QCT measurements

Two-dimensional areal BMD of the proximal femur can be obtained from 3-D QCT. This technique
(CTXA) generates a 2-D image that is analogous to hip DXA image and can be analyzed using the same
regions of interest [9,58]. The CTXA femoral neck T-scores can be directly compared to DXA T-scores
that use the NHANES reference data [39]. WHO diagnostic categories should only be assigned based on
CTXA hip T-score, not spine QCT T-score. The femoral neck CTXA BMD measurement can also be
used to determine fracture risk using the Fracture Risk Assessment Tool (FRAX) [59].

Unlike spine QCT measurements, which are optimally obtained using noncontrast CT examinations,
CTXA values from both enhanced and unenhanced CT scans can be used [60].

2. Spine QCT measurements

Currently there are no consensus standards for assigning diagnostic categories based on spine QCT
measurements. Although some QCT software manufacturers provide spine T-scores, these should not be
used to assign a diagnostic category using the World Health Organization (WHO) DXA guidelines.
Instead, the following diagnostic cut points may be used for assigning a spine QCT diagnostic category
approximately equivalent to the WHO guidelines

QCT Trabecular Spine BMD Range Equivalent WHO Diagnostic Category

BMD > 120 mg/cm3 Normal
80 mg/cm3 ≥ BMD ≥ 120 mg/cm3 Osteopenia
BMD < 80 mg/cm3 Osteoporosis

The above categories were derived by selecting thresholds that result in approximately the same fraction
of the population being assigned to a specific category based on QCT spine T-score as would be assigned
based on QCT hip T-score. The use of T-scores has been avoided in this categorization to reinforce the
fact that QCT spine T-scores and hip T-scores are frequently different. Assigning a WHO diagnostic
category based on a QCT spine T-score may result in overestimating a patient’s fracture risk.

D. For premenopausal women and men younger than 50 years, the BMD and Z-score should be reported for each
skeletal site examined. The WHO classification does not apply to these individuals (except for women in
menopausal transition). Z-scores above −2.0 are considered within the expected range for age. Individuals with Z-
scores of −2.0 and lower are considered to have low bone density for their age.

E. For children and adolescents, T-scores should not be reported. The WHO classification does not apply; the
terms “osteopenia” and “osteoporosis” should not be used. When BMD Z-scores are less than or equal to −2.0,
“Low bone mineral mass or bone mineral density” is the preferred terminology for pediatric QCT reports [64].

F. For follow-up examinations, comparison should be made to any prior comparable QCT examinations of the
same site. The precision error of the specific scanner(s) should be determined to identify whether any changes are
statistically significant [65]. Comparable scans include, in order of decreasing validity:

1. Previous examinations on the same well-maintained unit.

2. Previous examinations on another unit from the same manufacturer.
3. Previous examinations on a unit from another manufacturer, with results reported in standardized units.

G. Because of radiation dose considerations, least significant change parameters are not used for clinical
evaluations, although they may be obtained for research purposes. Appropriate quality assurance procedures
should be performed according to hardware and software manufacturers’ guidelines. In children, QCT protocols
should be modified and optimized to minimize radiation exposures [66].

PRACTICE PARAMETER 6 QCT

H. When assessing muscle mass using QCT, additional factors should be considered:

1. Muscle is the largest protein reservoir in the body and is considered an important biomarker of a patient's
physiologic reserves.
2. Muscle depletion may be seen with numerous conditions, including age-related sarcopenia and cancer-
related cachexia, and is associated with increased risk for adverse outcomes including functional decline
and mortality[67].
3. Most commonly measured muscle metrics on QCT are muscle cross-sectional area (in cm2) and muscle
attenuation (in HU) [68].
4. A single-axial abdominopelvic CT image at the L3 or L4 level commonly used to segment the psoas, the
paraspinous, or all visualized muscles on the image.
5. There is no consensus on analytic protocols (eg, measurement level, anatomy measured, software used)
and diagnostic cut-points normalization for age, sex, height, and ethnicity) [68]. For example, the L3
Skeletal Muscle Index values for diagnosing sarcopenia (measured in cm2/m2) are often stratified by sex,
BMI, and disease (eg, for patients with cancer, <41 for women, <34 for normal or underweight men, <53
for overweight or obese men) [69]. Low muscle attenuation has also been used to help diagnose
sarcopenia, with diagnostic cut points ranging from 30 HU [70] to 41 HU [69].
6. Intravenous contrast administration and the timing of subsequent CT image acquisition can significantly
change the attenuation values of muscles [71].
7. QCT for the diagnosis of sarcopenia is expected to grow because of a new ICD‐ 10 diagnostic code
(M62.84) [72], many pharmaceutical agents in development [73,74], and the evolution of machine
learning techniques for automated image analysis [75].

V. DOCUMENTATION

Reporting should be in accordance with the ACR Practice Parameter for Communication of Diagnostic Imaging
Findings [76].

A. For evaluation of osteoporosis in postmenopausal women and men older than 50 years using phantom-based
QCT, reports of the hip should include the BMD (in g/cm²) for area density, T-score, and WHO diagnostic
classification while reports of the spine should include BMD (in mg/cm3) for trabecular volumetric density.

B. QCT hip BMD (CTXA) may be used to obtain a fracture risk using the FRAX tool.

C. In premenopausal women, men younger than 50, and children, the QCT reports should include BMD values
and Z-scores. Z-scores above −2.0 are within the expected range. Z-scores of −2.0 or lower are considered to be
below the expected range for age.

D. In children and adolescents, QCT reports should include BMD values and Z-scores. Z-scores should be height
adjusted, when possible. Z-scores above −2.0 are within the expected range. Z-scores of −2.0 or lower are
considered to be below the expected range for age. The terms “osteopenia” and “osteoporosis” should not be used
in QCT reports [77]. T-scores should not be reported.

E. The QCT report should indicate whether artifacts or other technical issues may have influenced the reported
BMD measurement(s). A statement comparing the current study to prior available comparable studies should
include an assessment of whether any changes in measured BMD are statistically significant. Recommendations
for and the timing of follow-up QCT studies may be included. When appropriate, recommendations for alternative
modality densitometry examinations, ancillary imaging tests, or other diagnostic measures should be provided.

F. The QCT report should mention relevant incidental finding, such as vertebral compression fractures or other
fragility fractures. These findings may result in initiation of treatment for osteoporosis, regardless of the measured
BMD. Guidance regarding reporting of additional incidental findings not related to bones can be found elsewhere
[78].

PRACTICE PARAMETER 7 QCT

VI. EQUIPMENT QUALITY CONTROL

QCT quality control is extremely important for accuracy in sequential monitoring of the effectiveness of therapy
or progression of disease. All three of the methods for acquiring QCT provide accurate BMD determinations
suitable for assessing bone status. There are, however, differences in their precision, which results in different
sensitivities in detecting significant change in BMD through serial measurement comparisons. Precision is
typically best when the patient and the calibration standard are imaged simultaneously, and volumetric QCT units
often have better precision because of their reduced dependence on operator skills, such as patient positioning and
data processing.

Quality control is generally implemented at 2 levels. The first is maintenance of the CT system used to acquire
image data. The second is maintenance of the QCT software, phantoms, and associated accessories.

A. CT System – For the CT system, basic quality control procedures, as specified by the manufacturer, should be
performed and recorded by a trained technologist. The results should be interpreted immediately upon completion
according to the guidelines provided by the manufacturer to ensure proper system performance. If a problem is
detected according to manufacturer guidelines, the service representative should be notified, and patients should
not be examined until the equipment has been cleared for use.

B. QCT Phantoms – Precision error measurements of the phantom or standard should be performed on a
schedule according to manufacturer’s specifications and the results recorded. The results of the phantom
measurements should not exceed the specifications or recommendations of the manufacturer and generally should
be within 1%.

C. For the QCT software, basic quality control procedures, as specified by the manufacturer, should be
performed and recorded by a trained technologist. The results should be interpreted immediately upon completion
according to the guidelines provided by the manufacturer to ensure proper system performance. If a problem is
detected according to manufacturer guidelines, the service representative should be notified, and patients should
not be examined until the software has been cleared for use.

D. Equipment performance monitoring should be in accordance with the ACR-AAPM Technical Standard for
Diagnostic Medical Physics Performance Monitoring of Computed Tomography (CT) Equipment [79].

VII. RADIATION SAFETY IN IMAGING

Radiologists, medical physicists, registered radiologist assistants, radiologic technologists, and all supervising
physicians have a responsibility for safety in the workplace by keeping radiation exposure to staff, and to society
as a whole, “as low as reasonably achievable” (ALARA) and to assure that radiation doses to individual patients
are appropriate, taking into account the possible risk from radiation exposure and the diagnostic image quality
necessary to achieve the clinical objective. All personnel that work with ionizing radiation must understand the
key principles of occupational and public radiation protection (justification, optimization of protection and
application of dose limits) and the principles of proper management of radiation dose to patients
(justification,optimization and the use of dose reference levels)
http://www-pub.iaea.org/MTCD/Publications/PDF/Pub1578_web-57265295.pdf

Nationally developed guidelines, such as the ACR’s Appropriateness Criteria® should be used to help choose the
most appropriate imaging procedures to prevent unwarranted radiation exposure.

Facilities should have and adhere to policies and procedures that require varying ionizing radiation examination
protocols (plain radiography, fluoroscopy, interventional radiology, CT) to take into account patient body habitus
(such as patient dimensions, weight, or body mass index) to optimize the relationship between minimal radiation
dose and adequate image quality. Automated dose reduction technologies available on imaging equipment should
be used whenever appropriate. If such technology is not available, appropriate manual techniques should be used.

PRACTICE PARAMETER 8 QCT

Additional information regarding patient radiation safety in imaging is available at the Image Gently® for
children (www.imagegently.org) and Image Wisely® for adults (www.imagewisely.org) websites. These
advocacy and awareness campaigns provide free educational materials for all stakeholders involved in imaging
(patients, technologists, referring providers, medical physicists, and radiologists).

Radiation exposures or other dose indices should be measured and patient radiation dose estimated for
representative examinations and types of patients by a Qualified Medical Physicist in accordance with the
applicable ACR technical standards. Regular auditing of patient dose indices should be performed by comparing
the facility’s dose information with national benchmarks, such as the ACR Dose Index Registry, the NCRP
Report No. 172, Reference Levels and Achievable Doses in Medical and Dental Imaging: Recommendations for
the United States or the Conference of Radiation Control Program Director’s National Evaluation of X-ray
Trends. (ACR Resolution 17 adopted in 2006 – revised in 2009, 2013, Resolution 52).

VIII. QUALITY CONTROL AND IMPROVEMENT, SAFETY, INFECTION CONTROL, AND

PATIENT EDUCATION

Policies and procedures related to quality, patient education, infection control, and safety should be developed and
implemented in accordance with the ACR Policy on Quality Control and Improvement, Safety, Infection Control,
and Patient Education appearing under the heading Position Statement on QC & Improvement, Safety, Infection
Control, and Patient Education on the ACR web site (https://www.acr.org/Clinical-Resources/Practice-
Parameters-and-Technical-Standards).

ACKNOWLEDGEMENTS

This practice parameter was revised according to the process described under the heading The Process for
Developing ACR Practice Parameters and Technical Standards on the ACR website
(https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards) by the Committee on
Body Imaging (Musculoskeletal) of the Commission on Body Imaging and the Committee on Practice Parameters
– General, Small, and Rural and the Committee on Practice Parameters – Pediatric Radiology, of the
Commissions on General, Small, Emergency and/or Rural Practice, and Pediatric Radiology, in collaboration with
the SPR and the SSR.

Collaborative Committee
Members represent their societies in the initial and final revision of this practice parameter.

ACR SPR SSR

Leon Lenchik, MD Jeannette M. Pérez-Rosselló, MD Mary G. Hochman, MBA, MD
Robert D. Boutin, MD Richard E. A. Walker, MD
Kevin B. Hoover, MD
Sue C. Kaste, DO
Imran M. Omar, MD
Humberto Rosas, MD
Sandra Rutigliano, MD
Robert J. Ward, MD
Daniel E. Wessell, MD, Ph.D

Committee on Body Imaging (Musculoskeletal)

(ACR Committee responsible for sponsoring the draft through the process)

William B. Morrison, MD, Chair

Dawn M. Hastreiter, MD, PhD Kambiz Motamedi, MD
Mary K. Jesse, MD Catherine C. Roberts, MD
Kenneth S. Lee, MD David A. Rubin, MD, FACR
Suzanne S. Long, MD Naveen Subhas, MD
Jonathan S. Luchs, MD, FACR

PRACTICE PARAMETER 9 QCT

Committee on Practice Parameters – General, Small, Emergency and/or Rural Practices
(ACR Committee responsible for sponsoring the draft through the process)

Sayed Ali, MD, Chair

Marco A. Amendola, MD, FACR Pil S. Kang, MD
Gory Ballester, MD Jason B. Katzen, MD
Lonnie J. Bargo, MD Serena McClam Liebengood, MD
Christopher M. Brennan, MD, PhD Steven E. Liston, MD, MBA, FACR
Resmi A. Charalel, MD Gagandeep S. Mangat, MD
Charles E. Johnson, MD Tammam N. Nehme, MD
Candice A. Johnstone, MD Jennifer L. Tomich, MD
Padmaja A. Jonnalagadda, MD

Committee on Practice Parameters – Pediatric Radiology

(ACR Committee responsible for sponsoring the draft through the process)

Beverley Newman, MB, BCh, BSc, FACR, Chair

Lorna P. Browne, MB, BCh Sue C. Kaste, DO
Timothy J. Carmody, MD, FACR Tal Laor, MD
Brian D. Coley, MD, FACR Terry L. Levin, MD
Lee K. Collins, MD Marguerite T. Parisi, MD, MS
Monica S. Epelman, MD Sumit Pruthi, MBBS
Lynn Ansley Fordham, MD, FACR Nancy K. Rollins, MD
Kerri A. Highmore, MD Pallavi Sagar, MD

Lincoln Berland, MND, FACR, Chair, Commission on Body Imaging

Robert S. Pyatt, Jr, MD, FACR, Chair, Commission on General, Small, Emergency and/or Rural Practice
Marta Hernanz-Schulman, MD, FACR, Chair, Commission on Pediatric Radiology
Jacqueline Anne Bello, MD, FACR, Chair, Commission on Quality and Safety
Matthew S Pollack, MD, FACR, Chair, Committee on Practice Parameters & Technical Standards

Comments Reconciliation Committee

Johnson Lightfoote, MD, FACR, Chair Leon Lenchik, MD
Mark Alson, MD, FACR, Co-Chair William B. Morrison, MD
Sayed Ali, MD Beverley Newman, MB, BCh, BSc, FACR
Jacqueline Anne Bello, MD, FACR Marguerite T. Parisi, MD, MS
Lincoln L. Berland, MD, FACR Jeannette M. Pérez-Rosselló, MD
Robert D. Boutin, MD Matthew S. Pollack, MD, FACR
Richard Duszak, Jr., MD Robert S Pyatt Jr, MD, FACR
Jonathan Flug, MD, MBA Humberto G. Rosas
Marta Hernanz-Schulman, MD, FACR Sandra Rutigliano, MD
Mary G. Hochman, MBA, MD Timothy L. Swan, MD, FACR, FSIR
Kevin B. Hoover, MD Robert J. Ward, MD
Sue C. Kaste, DO Richard E. A. Walker, MD
Paul A. Larson, MD, FACR

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*Practice parameters and technical standards are published annually with an effective date of October 1 in the
year in which amended, revised, or approved by the ACR Council. For practice parameters and technical
standards published before 1999, the effective date was January 1 following the year in which the practice
parameter or technical standard was amended, revised, or approved by the ACR Council.

Development Chronology for this Practice Parameter

2008 (Resolution 33)
Amended 2009 (Resolution 11)
Revised 2013 (Resolution 32)
Amended 2014 (Resolution 39)
Revised 2018 (Resolution 9)

PRACTICE PARAMETER 14 QCT