[Intl_DxMedPhys] Mammography Display QC

[Niall Phelan]

On the subject of display QC.....

We have for many years employed a standard configuration of two 5MP displays side-by-side for mammography reporting and perform QC according to European guidelines (EFOMP & UK; relevant standards extracted in boxes below) which in turn are based on AAPM TG-18 and subsequently TG-270.
However, there is one additional constraint on the luminance variation between the two displays (<5%) which doesn't appear to form part of the AAPM guidance. I have always felt this constraint makes sense for diagnostic reporting with two paired displays, and we have achieved this performance in practice for years (sometimes by adjusting the L(max) of both displays independently).
Equally, all the guidance documents specify the uniformity tolerance for a single display to be <30% but in practice, we typically measure this <10% across the entire luminance range.

Recently, while testing some new large format displays (12MP) which are split into two independent windows for side-by-side reporting, we haven't been able to achieve this 5% tolerance on L(max) for what are effectively two sides of the same display. In one case, we measure >15% difference and of course the L(max) can't be adjusted as before for two independent displays.
Equally, when we consider the large format display on its own or split into independent display windows, either configuration conforms to the 30% uniformity tolerance.

Ultimately, the questions are:
Does anyone in North America (or elsewhere) impose a similar constraint on paired displays?
Does it make sense to impose a 30% uniformity limit on each single display and then a tighter 5% constraint on the paired displays?
Is 30% too high anyway for luminance uniformity (CRTs could achieve this 20+ years ago)?


EFOMP:
[cid:image002.png at 01DBB42C.BCC5EC50]

UK:
[cid:image003.png at 01DBB42C.BCC5EC50]


Grateful to hear any thoughts on this,

Niall


Niall Phelan
Chief Physicist
BreastCheck | 36 Eccles Street | Dublin 7 | DO7 Y7C6

Tel: +353 1 8826247 | +353 87 6697095
Email: niall.phelan at screeningservice.ie<mailto:niall.phelan at screeningservice.ie> https://urldefense.com/v3/__http://www.screeningservice.ie__;!!KGKeukY!3hrUJN-eI9nOaEqr5AAbwr7kQzhWHTYnATrEobbuFpG_fYv9NA_xty1vMVtYGIOVj2onapjctvJa5CkhQ3AX2IU1RKh6DGwNOgTscAeDv3DW4UOwW85JNw$ <https://urldefense.com/v3/__https://scanmail.trustwave.com/?c=8024&d=_8io4eaUV8Y6Xv3u4L1TqLQa3OnjRz04sR_rEXtJgQ&u=https*3a*2f*2fscanner*2etopsec*2ecom*2f*3ft*3dddab9df86276a2c67244b679c60f18671b56bf3e*26d*3d2120*26u*3dwww*2escreeningservice*2eie*26r*3dshow__;JSUlJSUlJSUlJSUlJSUlJQ!!KGKeukY!3hrUJN-eI9nOaEqr5AAbwr7kQzhWHTYnATrEobbuFpG_fYv9NA_xty1vMVtYGIOVj2onapjctvJa5CkhQ3AX2IU1RKh6DGwNOgTscAeDv3DW4UOF2eyz4A$ >
[cid:image004.jpg at 01DBB42C.BCC5EC50]


#####################################################################################
Scanned by MailMarshal - M86 Security's comprehensive email content security solution. 
Download a free evaluation of MailMarshal at https://urldefense.com/v3/__http://www.m86security.com__;!!KGKeukY!3hrUJN-eI9nOaEqr5AAbwr7kQzhWHTYnATrEobbuFpG_fYv9NA_xty1vMVtYGIOVj2onapjctvJa5CkhQ3AX2IU1RKh6DGwNOgTscAeDv3DW4UO5KzqMGQ$ 
#####################################################################################

This email and any files transmitted with it are confidential and intended
solely for the individual or entity to whom they are addressed. If you received
this email in error, please contact the sender immediately and delete the
email and any information transmitted with it. If you are not the intended
recipient of this email you should not disseminate, disclose, distribute, print, 
use, rely upon or copy this email or the contents of this email. Any views or 
opinions presented in this email are solely those of the author and do not 
necessarily represent those of the National Screening Service (NSS). As the 
security of this message cannot be guaranteed, the NSS does not accept any 
liability for any errors or omissions in the contents of this message arising as 
a result of email transmission. The recipient should check this email and any 
attachments for the presence of viruses. The NSS accepts no liability for any 
loss or damage caused by any virus transmitted by this email.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.osu.edu/mailman/private/intl_dxmedphys_wd_osu_list/attachments/20250423/8d7717e8/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.png
Type: image/png
Size: 15730 bytes
Desc: image002.png
URL: <https://lists.osu.edu/mailman/private/intl_dxmedphys_wd_osu_list/attachments/20250423/8d7717e8/attachment.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image003.png
Type: image/png
Size: 9791 bytes
Desc: image003.png
URL: <https://lists.osu.edu/mailman/private/intl_dxmedphys_wd_osu_list/attachments/20250423/8d7717e8/attachment-0001.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image004.jpg
Type: image/jpeg
Size: 1345 bytes
Desc: image004.jpg
URL: <https://lists.osu.edu/mailman/private/intl_dxmedphys_wd_osu_list/attachments/20250423/8d7717e8/attachment.jpg>