[Intl_DxMedPhys] MQSA - Manufacturer PM vs ACR DM QC manual

Hintenlang, David David.Hintenlang at osumc.edu
Mon Jun 1 12:35:44 EDT 2026


Is it possible that they just did not test tube output and dose during the PM and therefore cannot confirm that it passed?
David

David Hintenlang, PhD, DABR, FACR, FAAPM, FACMP
Professor and Chief of Medical Physics
Department of Radiology, Ohio State University Wexner Medical Center
Suite 450, 395 W. 12th Avenue, Columbus , OH 43210
614-366-0684 Office
[The Ohio State University]



From: Intl_dxmedphys_wd_osu_list <intl_dxmedphys_wd_osu_list-bounces at lists.osu.edu> On Behalf Of Milman, Rebecca via Intl_dxmedphys_wd_osu_list
Sent: Monday, June 1, 2026 12:21 PM
To: Tao, Ashley T <attao at emplifyhealth.org>; DxMedPhys List <intl_dxmedphys_wd_osu_list at lists.osu.edu> <intl_dxmedphys_wd_osu_list at lists.osu.edu>
Subject: Re: [Intl_DxMedPhys] MQSA - Manufacturer PM vs ACR DM QC manual

Update: I just received a PM service report (from Hologic) that stated that, “System passed all tests…to the exception of tube output and dose for all techniques. ” This raises a couple of questions, and I’m interested in other people’s experiences. 
Update:

I just received a PM service report (from Hologic) that stated that, “System passed all tests…to the exception of tube output and dose for all techniques.”

This raises a couple of questions, and I’m interested in other people’s experiences.

As a physicist, I don’t really know what it means if the “tube output and dose for all techniques” doesn’t pass during a PM. Without more information - including their internal pass/fail criteria - I’m not sure how to interpret this service report.

The other issue is related to Ashley’s original post. If the manufacturer’s tolerance for HVL is 0.01 mm Al, then it is problematic when you’re measuring HVL with a device with a measurement error > 0.01 mm Al. My experience has been that Hologic FSEs use the Raysafe X2 systems, which have a measurement error of 5% (below 25 kV) or 10% (above 25 kV). For a system with an HVL ~ 0.5 mm Al at 28 kV, then the measurement error is well above 0.01 mm Al.

So how do we (QMPs) address the situation where a manufacturer cites an issue based on a problematic performance criterion? For any other modality I would make a note of why the manufacturer’s criteria are problematic, but with the added regulatory requirements of mammography and the authority that MQSA wields over us all, what is a reasonable approach?

Should we start reporting measured values as a range of values to represent errors in the measurement equipment? There are regulations saying that manufacturers need to provide the facility with a service report, but how much information are they required to provide? It seems reasonable that they would need to provide a description of the test that failed and what their measurements were, but does anyone get that in their service reports?

Rebecca.



Rebecca Milman, Ph.D., DABR
Division Chief, Radiological Sciences | Associate Professor
Department of Radiology
University of Colorado Anschutz
720.848.6625

From: Intl_dxmedphys_wd_osu_list <intl_dxmedphys_wd_osu_list-bounces at lists.osu.edu<mailto:intl_dxmedphys_wd_osu_list-bounces at lists.osu.edu>> on behalf of Tao, Ashley T via Intl_dxmedphys_wd_osu_list <intl_dxmedphys_wd_osu_list at lists.osu.edu<mailto:intl_dxmedphys_wd_osu_list at lists.osu.edu>>
Date: Tuesday, May 19, 2026 at 2:27 PM
To: DxMedPhys List
<intl_dxmedphys_wd_osu_list at lists.osu.edu<mailto:intl_dxmedphys_wd_osu_list at lists.osu.edu>>
Subject: [Intl_DxMedPhys] MQSA - Manufacturer PM vs ACR DM QC manual
[External Email - Use Caution]
Dear DxMedPhys Listerv,

 I am wondering if anyone who is using the ACR DM QC manual has had any experience with MQSA inspectors giving citations for not following up with PM specifications.

Let me set the scene:

  1.  Our biomed engineer performed service on our unit and determined HVL to be outside of Hologic specs of +/-0.01 mm Al from their baseline/reference value. At 28kV, hologic baseline was 0.513 mm Al, and biomed measured 0.517. We were due for annual testing about a month and a half from the discovery. biomed asked if they could schedule PM for the day before physics testing. Since we were well above the minimum HVL requirement of 0.28 mm Al, we agreed.
MQSA inspectors said that ACR DM QC Test summary (mee report), Beam quality (HVL) assessment failures must be corrected before clinical use. Our HVL passes the ACR DM QC manual, but because biomed failed it, they said we needed to correct before clinical use and have an MEE.

  1.  Our biomed engineer performed service on our unit and determined AEC performance to be outside Hologic's specifications @ 2cm. Hologic references a range of EI values, whereas ACR DM QC manual specifies the SNR needs to be within +/-15% of the MEE. These two metrics are not comparable. We did perform a partial MEE because we were not certain whether or not we needed to. It turns out the MEE SNR was 22.34 and after AEC calibration, the new MEE SNR was 22.21. The MEE was completed 34 days after service but we were cited because it needed to be within 30 days. How do you reconcile the metrics used by Hologic vs ACR DM QC manual if they are not comparable?

  1.  Our biomed engineer performed service on our unit and determined target dose to be outside Hologic's specifications of +/-0.1 mGy. The ACR DM QC manual specifies the target dose for a CC view of the ACR DM QC phantom to be <=3 mGy and that the unit AGD must be within +/-25% of the calculated AGD. Again, Hologics metrics are different than the ACR DM QC manual. We are well within specifications, but because biomed failed it and we did not service it within 30 days, we were cited.

We showed the MQSA inspectors the service report and explained what the results were but they didn't seem to care and said that we would need to provide a corrective action letter before escalating to their next level inspector. It is my understanding that Hologic PM specs are more stringent for optimal performance. The ACR DM QC manual does not specify a timeline to address deficiencies in PM except for if there is relevant service and a finding were to be out of compliance with the ACR DM QC manual then you would need appropriate follow-up (e.g. immediately before clinical use versus 30 days). We are writing a response letter addressing these citations, but I would appreciate any input this group may have regarding their experience w/ inspectors and PMs being out of spec.

On a side note, if HVL is out of Hologic spec (but within MQSA requirements), and my biomed engineer needs to recalibrate but it also requires them to recalibrate AEC as part of the process, it seems that there would need to be on-site physicist testing of the AEC because according to  ACR DM QC manual - Table 3 Medical Physicist Involvement in Equipment Adjustments, Changes or Repairs(pg 138) - are any of you basically having to do MEEs every time your PMs are just a little bit out of spec?

Looking forward to hearing about your experiences.

Thanks
Ashley
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osu.edu/pipermail/intl_dxmedphys_wd_osu_list/attachments/20260601/7d27efc3/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.png
Type: image/png
Size: 8636 bytes
Desc: image001.png
URL: <http://lists.osu.edu/pipermail/intl_dxmedphys_wd_osu_list/attachments/20260601/7d27efc3/attachment.png>


More information about the Intl_dxmedphys_wd_osu_list mailing list