[Intl_DxMedPhys] GE Pristina Flat Field Uniformity

[Wunderle, Kevin]

Hi Matt,

I can offer an informed speculation. Many moons ago, I experienced something very similar on half a dozen GE Senograph FFDM units. The issue we encountered was due to imperfections in the x-ray filters and the imaging system's inability to perfectly align the filter wheel once it cycled.

Our experience mirrored your description with similar artifacts. After performing a flat-field calibration, the flat-field images looked great until the filter wheel was rotated. This could be done manually on the system interface, or it could happen automatically when the system was rebooted.

I suggest you (or your service person) perform your flat-field calibration, reshoot your flat-field artifact eval (which should look great), then manually cycle the filter several times and reshoot. If this is the cause, those artifacts will reappear. Repeat this for both the Rh and Ag filters.

Unfortunately, on the older GE systems, there was no way to improve the filter wheel positioning accuracy. When we experienced the issue, we shut down six units and GE flew in mammo experts from Buc, France to investigate and mitigate the problem. The only solution was to obtain hand-picked filters from China that were as close to perfectly flat as possible which, for all intent and purpose, resolved the issue.

Let us know if this turns out to be the root cause.

All the best,
Kevin

[The Ohio State University]
Kevin Wunderle, PhD, FAAPM, FACR
Professor, Department of Radiology
Diagnostic Medical Physicist
395 W. 12th Avenue,
Floor 4, Room 424
Columbus, OH, 43210
216-245-5513 Mobile
kevin.wunderle at osumc.edu<mailto:kevin.wunderle at osumc.edu>


From: Intl_dxmedphys_wd_osu_list <intl_dxmedphys_wd_osu_list-bounces at lists.osu.edu> On Behalf Of Palmer, Matthew R. (BIDMC - Radiology) via Intl_dxmedphys_wd_osu_list
Sent: Monday, January 26, 2026 4:39 PM
To: DxMedPhys List <intl_dxmedphys_wd_osu_list at lists.osu.edu>
Subject: [Intl_DxMedPhys] GE Pristina Flat Field Uniformity

Dear Colleagues, Multiple times recently, I've found artifacts when performing the Artifact Eval and Flat Field uniformity test, on the 2D Rh/Ag acquisitions for the GE Pristina mammo unit. I've pasted in a portion of my iPhone snapshot
Dear Colleagues,

Multiple times recently, I've found artifacts when performing the Artifact Eval and Flat Field uniformity test, on the 2D Rh/Ag acquisitions for the GE Pristina mammo unit.  I've pasted in a portion of my iPhone snapshot from the AWS display.  The image quality isn't pristine(a) and I've introduced a Moire pattern (there's no 'zipper'-like artifact in reality) but I think you can see the mottled appearance pretty clearly.

After the FSE runs the gain cal, the artifacts disappear - for about a day then reappear.

FSE's feedback from GE experts is that not to worry - the artifacts won't affect clinical images.  That's hard to swallow.

I was astonished that the tech's weren't picking up the artifacts in their weekly QC so I ran their Flat Field test from the tech IQST Weekly QC page.  The images shown briefly (but not saved as far as I can tell) during the test sequence look perfect (although you can't adjust the window/level).

I'm wondering if anyone has had this problem or can shed any light on it.

Matt Palmer
BIDMC Radiology



Matthew R. Palmer, PhD, DABR
Director, Medical Imaging Physics, Department of Radiology
Assistant Professor, Harvard Medical School
Beth Israel Deaconess Medical Center
330 Brookline Avenue
Boston, MA 02215
office: 617-667-0176 fax: 617-667-2770
mobile: 617-794-1736 pager: 617-632-7243 #32214

________________________________
PLEASE NOTE: This message is intended for the use of the person to whom it is addressed. It may contain information that is privileged, confidential and exempt from disclosure under applicable law. If you are not the intended recipient, your use of this message for any purpose is strictly prohibited. If you have received this communication in error, please delete the message and notify the sender so that we may correct our records. See our web page at https://urldefense.com/v3/__http://www.bilh.org__;!!KGKeukY!yt9JpJEOf2q1wUEH6eCNKxbfnF5c9tZDOeFU90GRaUC6iKs2wXToaENsVthHhagZPoFUd17GXOpAEkXJMjXcEVO7ff8tjfWzMGFtttzrq3NPqvQLlg$ <https://urldefense.com/v3/__http:/www.bilh.org__;!!KGKeukY!yPXjQjwtVfXFt-7mTxRycQxsuL5wT3jVEnZVQtVDhgKLkcWAtRAcVpzHasCOwejFq3t4iE207kdiJ4S7kfrqV3zLI7pq7IHjXHYpMUWnz72j2EY$> for a full directory of Beth Israel Lahey Health sites, staff, services and career opportunities.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.osu.edu/mailman/private/intl_dxmedphys_wd_osu_list/attachments/20260127/00eb4a10/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.png
Type: image/png
Size: 3605 bytes
Desc: image001.png
URL: <https://lists.osu.edu/mailman/private/intl_dxmedphys_wd_osu_list/attachments/20260127/00eb4a10/attachment.png>