Revision History


All ACR Nuclear Medicine accredited facilities and those applying for accreditation must maintain a documented quality control (QC) program. As part of the accreditation process, facilities must demonstrate compliance with the ACR requirements for QC by providing:

  • The most recent physicist report for each unit, including the annual performance tests descripted below including the most recent dose calibrator quarterly linearity and annual accuracy testing

  • Documentation of corrective action (if the physicist report indicates areas where corrective action is needed)

  • The most recent NRC and/or state inspection results (report) for the facility

  • Documentation of written responses to any violations noted in the NRC and/or state inspection report


Acceptance Testing

Acceptance tests must be performed on systems when they are installed. Initial testing of imaging equipment must be performed upon installation and should be completed before clinical use. This testing should be more comprehensive than periodic performance testing and should be consistent with current acceptance testing practice.


Annual Physics Survey

A physics survey must be performed on each nuclear medicine unit at least annually. The ACR realizes that surveys cannot usually be scheduled exactly on the anniversary date of the previous survey; therefore, a period of up to 14 months between surveys is acceptable. These tests do not need to be as rigorous as acceptance tests but must be a comprehensive suite of individual measurements that ensure adequate sensitivity for detecting detrimental changes in performance. A practicing qualified medical physicist (QMP) may perform these tests. Alternatively, the tests may be performed by properly trained individuals approved by the medical physicist using National Electrical Manufacturers Association (NEMA) protocols and/or other appropriate testing protocols developed and approved by the QMP. The test results must be reviewed by the QMP and documented in the annual survey report. As a part of this annual survey the QMP should meet with the supervising physician and the QC technologist to review the results of the survey and the effectiveness of the technologist QC program, and to recommend any corrective action or repairs that are needed. The supervising physician is responsible for assuring compliance with the recommendations of the medical physicist.


The annual physics survey must include, but not be limited to, the following performance tests:


Nuclear Medicine Performance Tests

Test

Description

Intrinsic Uniformity

Performed to ensure that the intrinsic detector integral and differential uniformity are sufficient to minimize the production of artifacts and ensure that patient abnormalities can be visualized without interference from the imaging system. These tests also monitor a scintillation unit for electronic problems and crystal deterioration (hydration).

System Uniformity

Performed to check all commonly used collimators for defects that might produce artifacts in planar and tomographic studies.

Intrinsic or System Spatial Resolution

Performed to ensure that the detector resolution is sufficient to provide satisfactory detection of lesions and delineate detail in clinical images.

Relative Sensitivity

Performed to verify that count rate per time between the two heads is within 5%.

Energy Resolution

Performed to verify that scatter rejection is sufficient to provide optimal contrast in clinical studies. Note: On some systems, energy resolution is very difficult to measure precisely.

Count Rate Parameters

Performed to measure the max count rate.

Monitor Evaluation

Performed to ensure that systems used to produce hard copy and monitors that are used for interpretation of clinical studies provide satisfactory image quality in terms of uniformity and spatial resolution.

Overall System Performance for SPECT Systems

Performed to quantitatively verify that SPECT systems provide satisfactory tomographic uniformity, contrast, and spatial resolution.

System Interlocks

Performed to verify that all system interlocks are operating as designed and that the system is safe and reliable for the nuclear medicine technologist to operate and for imaging patients.

Dose Calibrators

Performed annually to verify that readings from this instrument are accurate (accuracy test). All basic measurements of performance must be done at the time of installation and repeated after major repair. This test must be done according to protocols accepted by the appropriate state regulatory agencies or the NRC.

  • “Test” measurement of battery voltage (if applicable)

  • Zero adjustment (if applicable)

  • Background adjustment

  • Accuracy with NIST traceable standard

  • Linearity

  • Constancy test

Thyroid Uptake and Counting Systems

Performed to verify energy calibration, energy linearity, energy resolution, sensitivity, and reliability (Chi-squared test) for the measurement of organ function and the assay of patient samples.

  • I-123 capsule or long-lived standard calibration check

  • Count of background

  • High voltage/gain checks

  • Energy resolution

  • Chi-square test


Continuous Quality Control

The nuclear medicine technologist is responsible for verifying day-to-day operation of instruments and performing a few additional tests on a quarterly basis. These requirements represent the standard of practice and are in compliance with requirements and recommendations of the Joint Commission on the Accreditation of Healthcare Organizations (JCAHO) and state and federal agencies. Documentation of compliance with all quality control tests and corrective action is required as part of the application process.


The technologist QC program must include, but not be limited to, the following:


Nuclear Medicine Technologist's Quality Control Tests

Test

Description

Frequency

Intrinsic or System Uniformity

Performed to verify that components are properly functioning and provide a uniform image in response to a uniform flux of radiation

Each day of use

Intrinsic or System Spatial Resolution

Performed to quantitatively verify that detector spatial resolution is satisfactory for clinical imaging – The weekly resolution phantom is not necessary on cameras with pixilated detectors but a resolution image using either the ACR SPECT phantom (preferred) or a 4-quadrant bar phantom must be done at least semi-annually and also submitted with the accreditation application

Weekly

Center of Rotation

Performed to maintain ability to resolve details in clinical SPECT studies

Monthly

High-Count Floods for Uniformity Correction

Performed to correct for residual detector and collimator non-uniformity and to minimize the production of artifacts in clinical studies

As recommended by a qualified medical physicist

Overall System Performance for SPECT Systems

Performed to qualitatively verify that the system has maintained its capabilities with respect to tomographic uniformity, contrast, and spatial resolution that maximize the benefit in clinical studies. Technetium must be done at least semiannually; other radionuclides may be tested on alternate quarters.

Semiannually (quarterly recommended)

Dose Calibrators

  • Daily: Tests are performed to verify that the calibrator is accurate and reliable for the assay of doses administered to patients

  • Quarterly: A linearity test must be performed to document that accurate readings are provided through the entire range of activities used clinically. Other qualified personnel may do these tests

  • Semiannually: All non-exempt radionuclide sources must be tested to verify that radioactivity is not leaking from the sources. Other qualified personnel may also do these tests

Daily, quarterly, and semiannually, as indicated

Thyroid Uptake and Counting Systems

Standards are measured to verify energy calibration and sensitivity for the measurement of organ function and the assay of patient samples

Each day of use


Preventive Maintenance

Preventive maintenance must be scheduled, performed, and documented by a qualified service engineer on a regular basis. Service performed to correct system deficiencies must also be documented and service records maintained by the facility.



Revision History for this Article

Date

Section

Description of Revision(s)

12-12-19

All

Article created; FAQs incorporated; No criteria changes




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