Mammography Equipment Evaluations

Questions  Decision Tree  Table  Key Words/Related Topics

Citation:

900.12(e)(10): Mammography equipment evaluations. Additional evaluations of mammography units or image processors shall be conducted whenever a new unit or processor is installed, a unit or processor is disassembled and reassembled at the same or a new location, or major components of a mammography unit or processor equipment are changed or repaired. These evaluations shall be used to determine whether the new or changed equipment meets the requirements of applicable standards in paragraphs (b) and (e) of this section. All problems shall be corrected before the new or changed equipment is put into service for examinations or film processing. The mammography equipment evaluation shall be performed by a medical physicist or by an individual under the direct supervision of a medical physicist.

Approved Alternative Standard:

Conducting the Mammography Equipment Evaluation After a Software Upgrade Under Medical Physicist Oversight

Manufacturer's software modification of the AEC

Discussion:

According to Section 900.12(e)(10) of the regulations, mammography equipment evaluations must be conducted by a medical physicist for x-ray units and processors that are newly installed, have been disassembled and reassembled, or have undergone major repairs. Furthermore, such evaluations “shall be used to determine whether the new or changed equipment meets the requirements of applicable standards in paragraphs (b) and (e) of this section.”

For an x-ray unit that is new to the facility, the word “applicable” refers to the following:

Performing all the annual tests listed in section (e)(5) [except (e)(5)(viii), which need not be included if no new cassettes are added], the “other modality” tests listed in (e)(6) (if applicable), the compression device performance test listed in (e)(4)(iii)(B), and the phantom image test listed in (e)(2); and

Verifying that the new x-ray unit meets the equipment standards listed in Sections (b)(1-10). These standards relate to the design aspects of the unit as provided by the manufacturer. Furthermore, if the new unit is a film-screen unit and is the first and/or the only one at the facility, then (b)(11), (b)(12), (b)(14), and (b)(15), which relate to the screen-film combination and the lighting and viewing conditions used at the facility, must also be verified.

Note: If new cassettes are also added, then the screen-film contact test listed in (e)(4)(ii) and the uniformity of screen speed listed in (e)(5)(viii) must be performed.

Note that an evaluation of the facility’s QA program, including the QC tests and corrective actions taken by the facility, is not included in mammography equipment evaluations (as described in paragraphs 1 and 2 above). However, such an evaluation is always included in the annual survey. 21 C.F.R. 900.12(e)(9).

For a new processor, the “applicable” equipment evaluation tests are described in question 7 below.

Question 1: When are "mammography equipment evaluations" required and who must conduct the evaluations?

Question 2: When performing an annual physics survey or mammography equipment evaluation on a unit with multiple target/filter combinations, what tests or measurements must be performed for each combination?

Question 3: Must a currently certified facility or a facility undergoing certification for the first time have the "final" written report of the equipment evaluation before clinically using a newly added or modified unit?

Question 4: Can a medical physicist sign-off on mammography equipment evaluation done by a surrogate if the medical physicist was not present during the evaluation?

Question 5: What are the minimum tests and/or reviews that the medical physicist must perform for a facility survey, survey of a mammography unit, mammography equipment evaluation of a unit or processor that has been installed or disassembled and reassembled, and an equipment evaluation of a unit or processor that has undergone a major repair?

Question 6: While performing a facility survey, unit survey, or equipment evaluation, the medical physicist determines that the unit fails a required test(s) and needs to be adjusted, changed, or repaired. After the adjustment, change, or repair has been completed, does the test(s) have to be repeated and must the medical physicist perform the test(s)?

Question 7: What constitutes a mammography equipment evaluation (what tests must the medical physicist perform) for a processor that has undergone major repairs or is a new processor to the facility?

Question 8: Must the mammography equipment evaluation report be sent to the facility within 30 days?

Question 9: The bucky assembly (cassette holder) is being replaced on our x-ray unit. Is it necessary that the medical physicist test and pass this prior to its use on patients?

Question 10: Under what circumstances must our medical physicist actually visit our facility in order to successfully carry out his/her responsibility to oversee our equipment-related quality assurance practices?

Question 11: For test failures, equipment evaluations and other adjustments, changes, or repairs, are there specific timeframes defining when the verification test(s) must be performed?

Question 1: When are "mammography equipment evaluations" required and who must conduct the evaluations?

Whenever a new unit or processor is installed, or a unit or processor is reassembled, or major components are changed or repaired, an evaluation of the mammography unit or image processor is required. The medical physicist should decide which tests need to be performed following a particular repair, and should explain the rationale behind his or her decision. Examples of major changes or repairs that would call for equipment evaluations are: replacement of an x-ray tube, collimator, AEC unit, AEC sensor, or x-ray filter. For the processor, a total overhaul would be an example of a major repair. Routine preventive maintenance, pump replacement, replacement of the developer or fixer racks, replacement of the control board or changes in chemistry brand are not examples of major changes or repairs and would not require evaluation by a medical physicist.

The mammography equipment evaluation is needed to verify that all functions that may have been affected by the change or repair have been successfully restored even if a full survey had recently been completed. The mammography equipment evaluation must be performed by a qualified medical physicist or by an individual under the direct supervision of the medical physicist. The evaluation will be used to determine whether the new or changed equipment meets the requirements of applicable standards in 900.12(b) and (e). All problems shall be corrected before the new or changed equipment is put into service for examinations or film processing. The facility must maintain (until the next inspection that verifies compliance) the report of the mammography equipment evaluation and all documentation showing that all problems identified in the mammography equipment evaluation were corrected before the equipment was used on patients. 21 C.F.R. 900.12(d)(2). The report should document the date(s) on which the mammography equipment evaluation was performed and who performed the evaluation.

Question 2: When performing an annual physics survey or mammography equipment evaluation on a unit with multiple target/filter combinations, what tests or measurements must be performed for each combination?

For a unit with multiple target/filter combinations, the following tests must be performed for each clinically used target/filter combination:

• Focal spot condition (for different target materials [tracks] only)

• X-ray field/light field/image receptor/compression paddle alignment (for different target materials [tracks] only)

• Beam quality and half-value layer

• System artifacts

Question 3: Must a currently certified facility or a facility undergoing certification for the first time have the "final" written report of the equipment evaluation before clinically using a newly added or modified unit?

No, however, the currently certified facility or a facility undergoing certification for the first time must have, at a minimum, a written document of the test results, provided by the medical physicist, before any clinical use of the new or modified equipment. This initial documentation can simply be a list of all applicable tests performed on the equipment with an indication that the equipment passed all the tests. Mammography equipment evaluations must be performed by qualified medical physicists and must determine whether the new or modified equipment meets the requirements of applicable standards stated in sections 900.12(b) and (e) of the final regulations.

Question 4: Can a medical physicist sign-off on an mammography equipment evaluation done by a surrogate if the medical physicist was not present during the evaluation?

No. The qualified physicist would have to be present during the equipment evaluation and, at a minimum, provide direct supervision over his/her surrogate (supervisee). Direct supervision means that the supervisor (if the supervision is done after 4/28/99, the supervising medical physicist must have qualified under the Master’s or higher pathway) is present to observe and correct, as needed, the performance of the supervisee. 21 C.F.R. 900.2(o)(2). This requires that the supervisor be in the room during the performance of the individual equipment tests to assure that any mistakes made by the supervisee are corrected before the test is completed. The supervisor must review any calculations made from, and any conclusions drawn from the test results, before those results are provided to the facility.

The goal of direct supervision is to provide reasonable assurance that any mistakes made by the supervisee are corrected before the tests are completed.

The supervisor must be identified in the report. The qualifications of the supervising medical physicist will be checked during the inspection. The names of all those being supervised should also be identified in the report.

Question 5: What are the minimum tests and/or reviews that the medical physicist must perform for a facility survey, survey of a mammography unit, mammography equipment evaluation of a unit or processor that has been installed or disassembled and reassembled, and an equipment evaluation of a unit or processor that has undergone a major repair?

For more information, check additional guidance about the specific item being installed, reassembled or repaired.

Question 6: While performing a facility survey, unit survey, or equipment evaluation, the medical physicist determines that the unit fails a required test(s) and needs to be adjusted, changed, or repaired. After the adjustment, change, or repair has been completed, does the test(s) have to be repeated and must the medical physicist perform the test(s)?

After the adjustment, change, or repair has been completed, the test(s) have to be repeated and must show that the unit is within the appropriate action limit (verification test). For failures of the tests described in 900.12(e)(8)(ii)(A), 900.12(e)(6), 900.12(e)(7) and/or after adjustments, changes, or repairs that are classified as major, the verification test must be passed prior to using the item clinically. Note: verification testing performed after a major repair must be performed on-site by the medical physicist as required by 900.12(e)(10).

For failures of the tests described in 900.12(e)(8)(ii)(B), the facility has a maximum of 30 days from the date of the initial test failure to correct the problem and pass the verification test. Facilities should have the verification test(s) performed (either by the medical physicist or by a qualified individual) as soon as possible after the adjustment, change, or repair is done, so as to allow time to repeat the adjustment, change, or repair if the equipment does not pass the verification test. Note: if the verification test is not passed within the 30 day time period, the item cannot be used clinically until such time as it is truly repaired and passes the test.

For non-major equipment adjustments, changes, or repairs that are performed for any reason other than for failure of a required test, the facility must correct any problems found and perform verification tests to ensure that the equipment remains in compliance with the regulations. This should be accomplished as soon as reasonably possible.

If the adjustment, change, or repair constitutes a "major repair (see Medical Physicist Involvement in Equipment Adjustments, Changes, or Repairs table )," the medical physicist must repeat the test(s) as part of the required follow-up equipment evaluation. If the adjustment, change, or repair does not constitute a "major repair," the test(s) can be performed by any qualified person (e.g. radiologic technologist or service representative with appropriate training/experience). However, in this circumstance, FDA recommends that the medical physicist be consulted during this process.

The following decision trees may be used to help in determining the timing and extent of physicist and facility involvement in response to test failures, equipment adjustments/changes/repairs and equipment evaluations.

Decision Tree #1. Failure of a test(s) described in 900.12(e)(8)(ii)(A): Use of test results, 900.12(e)(6): Quality control tests -- other modalities, 900.12(e)(7): Mobile units.

Decision Tree #2. Failure of a test(s) described in 900.12(e)(8)(ii)(B): Use of test results.

*Note: In some cases, failures of the test(s) described in 900.12(e)(8)(ii)(B) and non-major adjustments, changes, or repairs may necessitate a verification test(s) described in 900.12(e)(8)(ii)(A). In those cases where an item fails its 900.12(e)(8)(ii)(A) verification test(s), the item cannot be used until such time as the verification test is passed.

Decision Tree #3. Non-major equipment adjustment, change, or repair for any reason other than failure of a required test.

*Note: In some cases, failures of the test(s) described in 900.12(e)(8)(ii)(B) and non-major adjustments, changes, or repairs may necessitate a verification test(s) described in 900.12(e)(8)(ii)(A). In those cases where an item fails its 900.12(e)(8)(ii)(A) verification test(s), the item cannot be used until such time as the verification test is passed.

Decision Tree #4. Equipment evaluations (new equipment, reassembly, or major adjustments, changes, or repairs).

Question 7: What constitutes a mammography equipment evaluation (what tests must the medical physicist perform) for a processor that has undergone major repairs or is a new processor to the facility?

At a minimum, the following tests must be done for a processor that has been replaced, undergone major repairs, or is a new processor to the facility: processor testing as described in 900.12(e)(1), phantom testing as described in 900.12(e)(2), and applicable portions of the system artifact evaluation as described in 900.12(e)(5)(ix). The medical physicist must also verify that the appropriate chemical solutions are being used, as described in 900.12(b)(13). If a change in clinical technique factors (for the standard breast) is involved such that the dose could reasonably exceed 300 mrad (3.0 mGy), a determination of dose as described in 900.12(e)(5)(vi) must be done.

We recommend that the fixer retention test described in 900.12(e)(3)(i) be performed and, in those cases where the integrity of the darkroom has been compromised, that the darkroom fog test described in 900.12(e)(4)(i) also be performed.

Note also that these processor evaluations apply to all processors used clinically by the facility, even those at remote sites (if any).

Question 8: Must the mammography equipment evaluation report be sent to the facility within 30 days?

The regulations do not specify when the mammography equipment evaluation report must be sent to the facility. However, the facility cannot use the equipment until it has documentation (written preliminary or final equipment evaluation report) showing that the equipment passes all the appropriate tests.

Question 9: The bucky assembly (cassette holder) is being replaced on our x-ray unit. Is it necessary that the medical physicist test and pass this prior to its use on patients?

If the replacement includes the AEC detector, the medical physicist must evaluate the assembly prior to use on patients. If, however, the installation does not involve the replacement of the AEC detector(s) on the system, the exchange of bucky assemblies would not be considered a major repair and would therefore not require the medical physicist to evaluate the assembly prior to use on patients. There are tests that should be performed when the bucky is replaced (table artifacts, grid artifacts, and x-ray field/image receptor alignment). These particular tests require evaluation of images obtained with the new or modified equipment. In many cases, such images may be generated by facility personnel in consultation with the medical physicist but do not require the medical physicist to be physically present in the facility. The images may then be sent to the medical physicist for evaluation. If approved by the medical physicist, the facility may begin using the equipment. The medical physicist can then repeat the tests at the next annual survey.

Question 10: Under what circumstances must our medical physicist actually visit our facility in order to successfully carry out his/her responsibility to oversee our equipment-related quality assurance practices?

At a minimum, the medical physicist must be on-site to perform or to provide direct supervision for the performance of:

1. The annual survey;

2. Mammography equipment evaluations. A mammography equipment evaluation must be conducted whenever a new unit or processor is installed, a unit or processor is disassembled and reassembled at the same or a new location, or major components of a mammography unit or processor are changed or repaired.

Determining when a medical physicist must be on-site in connection with adjustments, changes, or repair of equipment requires further discussion. Adjustments, changes, or repairs of equipment can occur as corrective actions for problems that caused the equipment to fail a quality control test, as the result of an unexpected equipment failure, or as a measure intended to prevent possible future inadequate equipment performance. All adjustments, changes, or repairs must include some form of verification testing to demonstrate that the affected equipment meets the applicable standards.

As noted, in the case of major adjustments, changes, or repairs, the medical physicist is required to conduct a mammography equipment evaluation on-site to confirm that the applicable standards in 21 CFR 900.12(b) and (e) are met. FDA also recommends that the medical physicist have a role in some other changes or repairs through the provision of "medical physicist (MP) oversight." By "MP oversight," we mean that the medical physicist should be consulted as to whether an on-site visit is required or if other personnel can verify that the standards are met, with direction by telephone or printed material from the medical physicist if needed. Finally, FDA recognizes that there are adjustments, changes, or repairs for which verification (that the adjusted, changed, or repaired equipment meets standards) can be performed by other qualified personnel (e.g. radiologic technologist or service representative with appropriate training/experience) without involving the medical physicist. However, the facility can consult their medical physicist in these situations if they wish.

The first column of the table, "Medical Physicist Involvement in Equipment Repairs," lists the adjustments, changes, or repairs in which the regulations require a mammography equipment evaluation. It also includes a number of adjustments, changes, or repairs that do not require a mammography equipment evaluation. The second column indicates whether the item is considered by FDA to be a major adjustment, change, or repair. If so, it is stated in the third column that the "MP conducts evaluation in person." For other adjustments, changes, or repairs, the third column indicates that FDA recommends either "MP oversight" or "MP involvement optional." In cases where the recommendation is "MP oversight" or "MP involvement optional", the verification may be accomplished by a qualified individual (as described in the previous paragraph) other than the medical physicist.

It is important to remember that in all cases, even those where FDA is recommending "MP oversight" or verification by a non-medical physicist, that some form of verification testing must be included as part of the adjustment, change, or repair.

Table: Medical Physicist Involvement in Equipment Adjustments, Changes, or Repairs

For any adjustment, change, or repair not listed in the table below, or if the facility is unsure as to the full extent of the adjustment, change, or repair, the facility should consult their medical physicist to determine the proper extent of his or her involvement in evaluating the item.

* Internal adjustments refer to equipment adjustments that typically cannot be made by the operator

Question 11: For test failures, equipment evaluations and other adjustments, changes, or repairs, are there specific timeframes defining when the verification test(s) must be performed?

For failures of the tests described in 900.12(e)(8)(ii)(A), 900.12(e)(6), 900.12(e)(7) and/or after adjustments, changes, or repairs that are classified as major, the verification test must be passed prior to using the item clinically. Note: verification testing performed after a major adjustment, change, or repair must be performed on-site by the medical physicist.

For failures of the tests described in 900.12(e)(8)(ii)(B), the facility has a maximum of 30 days from the date of the initial test failure to correct the problem and pass the verification test. Facilities should have the verification test(s) performed (either by the medical physicist or by a qualified individual) as soon as possible after the adjustment, change, or repair is done, so as to allow time to repeat the adjustment, change, or repair if the equipment does not pass the verification test. Note: if the verification test is not passed within the 30 day time period, the item cannot be used clinically until such time as it is truly repaired and passes the test.

For non-major equipment adjustments, changes, or repairs that are performed for any reason other than for failure of a required test, the facility must correct any problems found and perform verification tests to ensure that the equipment remains in compliance with the regulations. This should be accomplished as soon as reasonably possible.

The decision trees included in the Question 6 answer may be used to help in determining the timing and extent of physicist and facility involvement in response to test failures, equipment adjustments/changes/repairs and equipment evaluations.

Key Words:

Equipment Evaluation

Repaired Equipment

Moved Equipment

Changed Equipment

Medical Physicist

Direct Supervision

Related Topics:

Medical Physicist Responsibilities

Medical Physicist Annual Survey

QC Records Retention Requirement for Replaced Equipment