[Intl_DxMedPhys] Question on CT Bowtie filter failures

[Philip Doyle]

Hi Mark/all, Yes a few years back a filter block was reinserted back to front after a tube change on a Toshiba Aquilion CT scanner. Amazingly it fitted, the reference sensors reconnected OK and the scanner passed it's manufacturer tests. Took some time to diagnose.Since then I always take an extra CTDIair measurement off-axis from isocentre for the relevant field sizes. Once bitten....Regards,Phil.

Hi all, AAPM TG 96. B is curious if anyone has ever had any experience of discovering an issue with a bowtie filter (or inherent filtration) through annual CTDI testing. Basically, observing a whacky result in Center/Periphery doses that was










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-------- Original message --------From: Mark Supanich via Intl_dxmedphys_wd_osu_list <intl_dxmedphys_wd_osu_list at lists.osu.edu> Date: 08/04/2025  16:40  (GMT+00:00) To: intl_dxmedphys_wd_osu_list at lists.osu.edu Subject: [Intl_DxMedPhys] Question on CT Bowtie filter failures 

Hi all,

AAPM TG 96.B is curious if anyone has ever had any experience of discovering an issue with a bowtie filter (or inherent filtration) through annual CTDI testing. Basically, observing a whacky result in Center/Periphery doses that was due to a filter issue.




Feel free to respond directly to me and not the list.








--

Mark P. Supanich, Ph.D., DABR, FAAPM (he/him)

Director – Diagnostic Medical Physics

Rush University System for Health

Associate Professor & Vice Chair for Physics and Informatics

Rush Medical College Department of Diagnostic Radiology and Nuclear Medicine











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