The American College of Radiology (ACR) was founded in 1963 to promote continuous quality improvement for imaging facilities. In 1995, to further its mission, the college introduced an ultrasound accreditation program. Today the program encompasses many different standards that facilities must meet and maintain for accreditation. Those standards apply to the sonographers performing the exams, the physicians reading the exams, the physical environment in which the exams are performed, policies and procedures, and—last but not least—the quality control program for the equipment, which is the focus of this article.

ACR ultrasound accreditation offers many benefits, and biomeds can play a crucial role in helping secure it for their facilities. But in order to support the efforts of departments seeking accreditation, HTM teams need to understand how to define, meet, and document ACR standards.

Benefits of ACR Accreditation

What are the advantages of ACR accreditation? While accreditation is voluntary, imaging facilities with accreditation from ACR or similar organizations have two distinct advantages over unaccredited facilities. The first is prestige: A facility can distinguish itself from others by having that seal of approval. The second is financial: Some state agencies and private insurance companies tie reimbursements to facilities with accreditation by ACR or a comparable national group.

Where do we as service and support providers fit into this equation? The ACR’s quality control standards for ultrasound systems specify maintenance procedures that must be performed on every ultrasound system within the accredited department at specific intervals, in order for that department to qualify for accreditation. Note that within a given facility, there are ultrasound systems in many departments—radiology, cardiology, emergency, obstetrics, labor and delivery, oncology, urology, and vascular—but not all departments may be accredited. Each organization should determine which specific departments aim to receive ACR certification. In most facilities, the department that performs breast imaging is the first to become ACR-accredited.

Preventive Maintenance Criteria

The ACR quality control program establishes performance and safety standards for gray-scale imaging that address penetration, sensitivity, and uniformity. Topics like electrical safety, mechanical operation, cleanliness, vertical/horizontal measurement accuracy, and low-contrast object detectability are also included in the standards. The images and reports documenting compliance must be available for every ultrasound system in hard-copy format.

The ACR standards also address safety and mechanical inspection of the system and transducers, which can be completed using eight standard questions.

  • Are all cables and cords intact?
  • Are the transducers intact?
  • Are the probes cleaned after each use?
  • Are the monitors cleaned after each use?
  • Are the air filters cleaned after each use?
  • Do the brakes work?
  • Are the casters securely fastened to the system?
  • Are the peripherals secured to the system?

When performing standard imaging tests, biomeds should evaluate the same two probes throughout the entire process using specific imaging parameters. This is done so that future evaluations will provide consistent results. Although all probes should be inspected, ACR mandates that the two tested probes also be the two most commonly used. Ideally, they should also be in different formats (for example, linear and curved). The imaging testing parameters include depth, output power, transmit zone location, and frequency. Each inspection should include these parameters to maintain the integrity of test results and to measure changes in system performance over time.

New Requirements

In June 2014, ACR introduced a new accreditation requirement to evaluate geometric accuracy. This test uses the ultrasound system calipers to measure known distances between test targets, although testing is only required for the mechanically scanned directions. The caliper readouts of the distance between the two targets must agree to within 1.5% axially, or vertically, and 2% laterally, or horizontally.

ACR also added a requirement to test ultrasound systems’ primary interpretation display performance. This test is only required if the reading takes place at the facility where the ultrasound is performed. The display characteristics evaluated may include gray-scale response, luminance calibration, presence of pixel defects, and overall image quality. As in the procedures detailed above, all test results and corrective actions must be documented. For example, if you discover signal dropout with a transducer during a preventive maintenance check, that condition needs to be recorded. After the transducer is repaired or replaced, the follow-up action taken also needs to be reported. All maintenance and repair documents must be kept onsite in hard copy for inspection. The department is required to document all quality assurance (QA) and maintenance visits for all accredited equipment.

More information on the latest ultrasound accreditation program requirements is available on the ACR website.

OEM Challenges

Meeting the ACR accreditation requirements can be complicated if your facility holds a service contract with an original equipment manufacturer (OEM) or uses a third-party service provider. You may have trouble acquiring the appropriate reports, or determining if your service provider follows the processes outlined by ACR.

For example, to meet several of its requirements, ACR recommends the use of a tissue-mimicking phantom or test object for tests verifying uniformity, geometric accuracy, system sensitivity, and contrast or spatial resolutions. Although use of a phantom is only recommended, performing some tests without one is not practical, especially if you are not well versed in operating the particular system you are maintaining. ACR does not specify that a particular phantom be used for these tests, but it does require that the phantom be serialized.

In addition, according to the ACR quality control document, “Continual quality control consists of performing the tests previously discussed annually, with routine QC testing being performed semiannually.” This routine QC testing consists of the same tests as in the annual inspection. Performing both the annual and routine inspections is crucial to evaluate the certified systems for degradation. In these instances, you need to communicate with your OEM or service provider in order to ensure their compliance and secure proper documentation.

Do you know how often the ultrasound equipment within an accredited department is tested? Are all ultrasound systems within that department being tested, including portable systems? (ACR does not distinguish between standard, mainframe-type systems, and portable systems.) Does your department’s PM or QA program meet ACR standards? Chances are that you are missing the answer to one or more of these questions.

Keep in mind also that manufacturer-recommended intervals for PMs have changed in recent years as equipment has evolved. A service manual from one major ultrasound manufacturer states that because the system does not have any high-wear items, no PM is mandatory. At the same time, this manufacturer recommends performing certain tests and procedures on a regular basis or taking other steps to conform to accrediting standards.

What does this mean? Even if your ultrasound system is under warranty or you have a service agreement, there is a good chance you are not in compliance with ACR requirements. The bottom line: It is not the manufacturer’s responsibility to perform semiannual inspections to maintain accreditation. The responsibility rests with the owner of the systems. We, as service and maintenance providers, must assist other departments with the technical portion of the accreditation process.

Other Standards

Besides ACR, there are many other ultrasound accreditation organizations. The American Institute of Ultrasound in Medicine (AIUM), the Intersocietal Commission for the Accreditation of Vascular Testing (formerly ICAVL), and the Intersocietal Commission for the Accreditation of Echocardiography Laboratories (ICAEL), among others, all set quality assurance standards for facilities. The ICAEL and IAC Vascular Testing protocols call for annual accuracy testing, using a phantom and routine cleaning program of the system, probes, and filters, while the AIUM standards call for “regular maintenance and calibration” and “appropriate electrical inspection of the equipment on a regular basis.”

Whichever group’s standards your facility follows, the biomedical team needs to be involved in order to support the efforts of departments seeking accreditation. Understanding each department’s accreditation goals allows us as service providers to comply with the standards. Communicating with your OEMs and third-party service providers will also help ensure your compliance and guarantee that all necessary documentation is available. For additional questions on the latest requirements, be sure to visit the appropriate website of the accrediting agency.

James K. Rickner is the training director at Conquest Imaging located in Stockton, Calif. Jim has worked on various electronic systems for over 25 years and in the ultrasound industry for over 9 years. Contact editorial director John Bethune at [email protected]

References

  1. American College of Radiology. Ultrasound Accreditation Program Requirements. Available at http://www.acr.org/Quality-Safety/Accreditation/Ultrasound. Accessed June 29, 2015.