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I was able to get the tech to do a retro recon with FC23 instead of FC26. Here are a couple of sample images (the original FC26 on top, and FC23 on the bottom). I think we found the culprit behind that weird enhancement! Per Tim’s comment, I</div>
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<p class="MsoNormal">I was able to get the tech to do a retro recon with FC23 instead of FC26. Here are a couple of sample images (the original FC26 on top, and FC23 on the bottom). I think we found the culprit behind that weird enhancement! Per Tim’s comment,
I also reminded her to pay attention to using the thins to make the MPRs. <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><img width="518" height="390" style="width:5.3958in;height:4.0625in" id="Picture_x0020_3" src="cid:image002.png@01DD1532.11F993E0"><o:p></o:p></p>
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<p class="MsoNormal"><img width="526" height="379" style="width:5.4791in;height:3.9479in" id="Picture_x0020_9" src="cid:image001.png@01DD1532.9F1BA4C0"><o:p></o:p></p>
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<p class="MsoNormal"><b><span style="font-family:"Arial",sans-serif;color:#639044;mso-ligatures:standardcontextual">Stephanie M. Leon, PhD, DABR, DABSNM</span></b><span style="font-family:"Arial",sans-serif;color:#78BE20;mso-ligatures:standardcontextual"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#00664F;mso-ligatures:standardcontextual">Chief of Diagnostic Medical Physics<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#00664F;mso-ligatures:standardcontextual">Associate Professor of Radiology<br>
<br>
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#00664F;mso-ligatures:standardcontextual">Tel (603) 650-3796<br>
Dartmouth-Health.org<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-top:12.0pt"><a href="https://urldefense.com/v3/__https://www.dartmouth-health.org/__;!!KGKeukY!3SswjjJmvvEmubaM7r0tukZVAx1a9cRC7Cy40KtrWLwfRYx-OBhxDByk-VCOa4Qq2XuL9u4l6Ktx5Y-E_iZqO9RXW3KhPvAV6t48jqialeGZ4ktZDuKNKw$"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#7F7F7F;text-decoration:none"><img border="0" width="211" height="60" style="width:2.1979in;height:.625in" id="Picture_x0020_15" src="cid:image005.png@01DD1532.11F993E0"></span></a><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#7F7F7F;mso-ligatures:standardcontextual"><o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Intl_dxmedphys_wd_osu_list <intl_dxmedphys_wd_osu_list-bounces@lists.osu.edu>
<b>On Behalf Of </b>Szczykutowicz, Timothy P via Intl_dxmedphys_wd_osu_list<br>
<b>Sent:</b> Thursday, July 16, 2026 10:58 AM<br>
<b>To:</b> intl_dxmedphys_wd_osu_list@lists.osu.edu<br>
<b>Subject:</b> Re: [Intl_DxMedPhys] [External] Re: CT artifact **EXTERNAL**<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="mso-line-height-alt:.75pt"><span style="font-size:1.0pt;color:white">Hey list, does anyone have a canon that could do a rretro-recon with FC 20-26 and share? Canon materials say the 26 kernel enhances contrast, wondering if this
could be explaining the hyper dense gyri near the skull? (it goes down when you move<o:p></o:p></span></p>
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<p class="MsoNormal" style="mso-line-height-alt:.75pt"><span style="font-size:1.0pt;color:white">Hey list, does anyone have a canon that could do a rretro-recon with FC 20-26 and share? Canon materials say the 26 kernel enhances contrast, wondering if this
could be explaining the hyper dense gyri near the skull? (it goes down when you move<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;color:black">Hey list, does anyone have a canon that could do a rretro-recon with FC 20-26 and share? Canon materials say the 26 kernel enhances contrast, wondering if this could be explaining the hyper dense
gyri near the skull? (it goes down when you move away from the skull, I spoke with Stephanie). I dont have a canon with these older kernel options. <o:p></o:p></span></p>
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<p class="elementtoproof"><span style="font-size:10.0pt;font-family:"Tahoma",sans-serif;color:black">Timothy P. Szczykutowicz, Ph.D., DABR<br>
Professor<br>
Departments of Radiology, Medical Physics and BME<br>
University of Wisconsin Madison<br>
Cell# </span><a href="tel:(716)%20560-7751" target="_blank"><span style="font-size:10.0pt;font-family:"Tahoma",sans-serif">1-716-560-7751</span></a><span style="font-size:10.0pt;font-family:"Tahoma",sans-serif;color:black"><br>
Office# 1-608-263-5729<br>
he/him/his</span><o:p></o:p></p>
<p class="elementtoproof"> <o:p></o:p></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black"> Intl_dxmedphys_wd_osu_list <</span><a href="mailto:intl_dxmedphys_wd_osu_list-bounces+tszczykutowicz=uwhealth.org@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list-bounces+tszczykutowicz=uwhealth.org@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">>
on behalf of Szczykutowicz, Timothy P via Intl_dxmedphys_wd_osu_list <</span><a href="mailto:intl_dxmedphys_wd_osu_list@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">><br>
<b>Sent:</b> Thursday, July 16, 2026 9:28 AM<br>
<b>To:</b> Stephanie M. Leon <</span><a href="mailto:Stephanie.M.Leon@hitchcock.org"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Stephanie.M.Leon@hitchcock.org</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">>;
</span><a href="mailto:intl_dxmedphys_wd_osu_list@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">
<</span><a href="mailto:intl_dxmedphys_wd_osu_list@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">>;
Li, Baojun <</span><a href="mailto:baojunli@bu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">baojunli@bu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">>; Tang, Xiangyang <</span><a href="mailto:xiangyang.tang@emory.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">xiangyang.tang@emory.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">><br>
<b>Subject:</b> Re: [Intl_DxMedPhys] [External] Re: CT artifact</span> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-line-height-alt:.75pt"><span style="font-size:1.0pt;color:white">It is a little sus that the cerebellum is enhancing so much within the well defined borders of the tentorium cerebelli (that hyper dense strip between the cerebelum
and the rest of the brain). I think the hyperdense region in the middle of the<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;color:black">It is a little sus that the cerebellum is enhancing so much within the well defined borders of the tentorium cerebelli (that hyper dense strip between the cerebelum and the rest of the brain).
I think the hyperdense region in the middle of the cerebellum on the images you showed is partly a result of some beam hardening near the t bone anatomy like previously discussed, but no cone angle or BH artifact is going to enhance the entire cereblumm like
that. If the complaint is just about the slightly higher hyperdensities here (see the image below from a routine head from my place, I put a cross hair on an axial and SA, you can see the hyper density part if away from the borders of the hounsfield's bar
region), this may be some BH from the temporal bone anatomy.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;color:black">So this dark/bright appearance can be thought of as the darkness from hounsdield bar between the t bone, and the brightness from traditional bone bleed through into brain, causing that cereblum
to have the appearance it does. But this is pretty common on most heads. I would have the rad review a few cases with you, or compare some CT priors for another patient who got the same protocol on the same scanner but has scans from another CT scanner in
your fleet as a prior. <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;color:black">As an aside, I would check how your site is making the reformats, they look like they are being made form too thick of source recons. On a canon scanner that you have, you can set the source volume
to have thin, like 0.5 or 1 right? Then make reformats from that thicker? The reformats you show look like they are thick made from this. Compare to my SA below, the correlations in noise are uniform image top-bottom left-right, wheraes your are longer top-bottom
which tells me the source slice was possibly too large? <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;color:black"><img border="0" width="1722" height="542" style="width:17.9375in;height:5.6458in" id="Picture_x0020_2" src="cid:image008.png@01DD1532.11F993E0"></span><span style="font-size:11.0pt;color:black"><o:p></o:p></span></p>
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<p class="xelementtoproof"><span style="font-size:10.0pt;font-family:"Tahoma",sans-serif;color:black">Timothy P. Szczykutowicz, Ph.D., DABR<br>
Professor<br>
Departments of Radiology, Medical Physics and BME<br>
University of Wisconsin Madison<br>
Cell# </span><a href="tel:(716)%20560-7751" target="_blank"><span style="font-size:10.0pt;font-family:"Tahoma",sans-serif">1-716-560-7751</span></a><span style="font-size:10.0pt;font-family:"Tahoma",sans-serif;color:black"><br>
Office# 1-608-263-5729<br>
he/him/his</span><o:p></o:p></p>
<p class="xelementtoproof"> <o:p></o:p></p>
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<div class="MsoNormal" align="center" style="text-align:center">
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black"> Intl_dxmedphys_wd_osu_list <</span><a href="mailto:intl_dxmedphys_wd_osu_list-bounces@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list-bounces@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">>
on behalf of Tang, Xiangyang via Intl_dxmedphys_wd_osu_list <</span><a href="mailto:intl_dxmedphys_wd_osu_list@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">><br>
<b>Sent:</b> Wednesday, July 15, 2026 3:12 PM<br>
<b>To:</b> Stephanie M. Leon <</span><a href="mailto:Stephanie.M.Leon@hitchcock.org"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Stephanie.M.Leon@hitchcock.org</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">>;
</span><a href="mailto:intl_dxmedphys_wd_osu_list@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">
<</span><a href="mailto:intl_dxmedphys_wd_osu_list@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">>;
Li, Baojun <</span><a href="mailto:baojunli@bu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">baojunli@bu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">><br>
<b>Subject:</b> Re: [Intl_DxMedPhys] [External] Re: CT artifact</span> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-line-height-alt:.75pt"><span style="font-size:1.0pt;color:white">Hi Stephanie, In addition to Baojun's comments, another possibility for the root cause for the artifacts can be the data inconsistency that is induced by the cone
angle during data acquisition, which may exist in either helical or axial scan.</span><span style="font-size:1.0pt;font-family:"Arial",sans-serif;color:white"> </span><span style="font-size:1.0pt;color:white"><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black">Hi Stephanie,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="color:black">In addition to Baojun's comments, another possibility for the root cause for the artifacts can be the data inconsistency that is induced by the cone angle during data acquisition, which may exist in either helical
or axial scan.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="color:black">Best regards,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="color:black">Xiangyang<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#174E86">Xiangyang Tang, PhD, DABR, FSPIE, FAAPM & FAIMBE<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#174E86">Professor of Radiology and Imaging Sciences<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#174E86">PI, Translational Research in CT Lab<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#174E86">Director, Medical Physics Imaging Residency Program<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#174E86">Department of Radiology and Imaging Sciences<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#174E86">Emory University School of Medicine<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#174E86"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#174E86">The book entitled "</span><span style="color:black"><a href="https://urldefense.com/v3/__https:/www.amazon.com/Spectral-Multi-Detector-Computed-Tomography-sMDCT/dp/0367137534?source=ps-sl-shoppingads-lpcontext&ref_=fplfs&psc=1&smid=ATVPDKIKX0DER__;!!KGKeukY!0OUypJHAAFg21kS7W3auLfH133sr72DMejboDtUYaxJXzaMB0DG8MxB799_4PdMGaaVlHi4SKKTXpW5M0nBDjacrHLFStAE_Z8b1uT7BM84iY1Jeyg$" title="https://www.amazon.com/Spectral-Multi-Detector-Computed-Tomography-sMDCT/dp/0367137534?source=ps-sl-shoppingads-lpcontext&ref_=fplfs&psc=1&smid=ATVPDKIKX0DER"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Spectral
Multi-Detector CT (sMDCT): Data Acquisition, Image Formation, Quality Assessment and Contrast Enhancement</span></b></a></span><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#174E86">"</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#174E86"><o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-family:"Calibri",sans-serif;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">Mail address:<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">Woodruff Memorial Research Building Rm 1215<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">101 Woodruff Circle<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">Atlanta, GA 30322<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">email:
</span><span style="color:black"><a href="mailto:xiangyang.tang@emory.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">xiangyang.tang@emory.edu</span></a></span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black"> Intl_dxmedphys_wd_osu_list <</span><a href="mailto:intl_dxmedphys_wd_osu_list-bounces+xiangyang.tang=emory.edu@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list-bounces+xiangyang.tang=emory.edu@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">>
on behalf of Li, Baojun via Intl_dxmedphys_wd_osu_list <</span><a href="mailto:intl_dxmedphys_wd_osu_list@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">><br>
<b>Sent:</b> Wednesday, July 15, 2026 2:40 PM<br>
<b>To:</b> Stephanie M. Leon <</span><a href="mailto:Stephanie.M.Leon@hitchcock.org"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Stephanie.M.Leon@hitchcock.org</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">>;
</span><a href="mailto:intl_dxmedphys_wd_osu_list@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">
<</span><a href="mailto:intl_dxmedphys_wd_osu_list@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">><br>
<b>Subject:</b> [External] Re: [Intl_DxMedPhys] CT artifact</span> <o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-line-height-alt:.75pt"><span style="font-size:1.0pt;color:white">Hi Stephanie, The cerebellum is near the temporal bone and the skull base, so it tends to be affected by beam hardening. The BH effect makes the pixels brighter.
I also observed some radial banding patterns, which may be the result of helical<o:p></o:p></span></p>
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<p class="xxxmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Hi Stephanie,</span><o:p></o:p></p>
<p class="xxxmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="xxxmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">The cerebellum is near the temporal bone and the skull base, so it tends to be affected by beam hardening. The BH effect makes the pixels brighter. I also
observed some radial banding patterns, which may be the result of helical interpolation or sagittal reformatting.</span><o:p></o:p></p>
<p class="xxxmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="xxxmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Baojun</span><o:p></o:p></p>
<p class="xxxmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="xxxmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="xxxmsonormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Intl_dxmedphys_wd_osu_list <</span><a href="mailto:intl_dxmedphys_wd_osu_list-bounces@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list-bounces@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">>
<b>On Behalf Of </b>Stephanie M. Leon via Intl_dxmedphys_wd_osu_list<br>
<b>Sent:</b> Wednesday, July 15, 2026 12:21 PM<br>
<b>To:</b> </span><a href="mailto:intl_dxmedphys_wd_osu_list@lists.osu.edu"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">intl_dxmedphys_wd_osu_list@lists.osu.edu</span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><br>
<b>Subject:</b> [Intl_DxMedPhys] CT artifact</span><o:p></o:p></p>
<p class="xxxmsonormal"> <o:p></o:p></p>
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<p class="xxxmsonormal"><span style="font-size:1.0pt;color:white">Hi all, I have an odd CT artifact that a radiologist brought to my attention. The top image has bright gyri on the right cerebrum. The 2nd image shows the gyri okay in the left cerebrum, but
very bright in the cerebellum. The cerebellum is also</span><o:p></o:p></p>
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<p class="xxxmsonormal">Hi all,<o:p></o:p></p>
<p class="xxxmsonormal"> <o:p></o:p></p>
<p class="xxxmsonormal">I have an odd CT artifact that a radiologist brought to my attention. The top image has bright gyri on the right cerebrum. The 2<sup>nd</sup> image shows the gyri okay in the left cerebrum, but very bright in the cerebellum. The cerebellum
is also very bright in the 3<sup>rd</sup> image. <o:p></o:p></p>
<p class="xxxmsonormal"> <o:p></o:p></p>
<p class="xxxmsonormal">This is from a Canon Aquilion Prime SP, helical acquisition, AIDR 3D recon and FC26 kernel. It is apparent in the axial images too, just a bit harder to see. The patient received an MRI to follow up, which was normal.<o:p></o:p></p>
<p class="xxxmsonormal"> <o:p></o:p></p>
<p class="xxxmsonormal">Any ideas??<o:p></o:p></p>
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<p class="xxxmsonormal"><img border="0" width="463" height="416" style="width:4.8229in;height:4.3333in" id="x_x_x_Picture_x0020_5" src="cid:image009.png@01DD1532.11F993E0"><o:p></o:p></p>
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<p class="xxxmsonormal"><img border="0" width="598" height="536" style="width:6.2291in;height:5.5833in" id="x_x_x_Picture_x0020_6" src="cid:image010.png@01DD1532.11F993E0"><o:p></o:p></p>
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<p class="xxxmsonormal"><img border="0" width="611" height="590" style="width:6.3645in;height:6.1458in" id="x_x_x_Picture_x0020_7" src="cid:image011.png@01DD1532.11F993E0"><o:p></o:p></p>
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<p class="xxxmsonormal"><b><span style="font-family:"Arial",sans-serif;color:#639044">Stephanie M. Leon, PhD, DABR, DABSNM</span></b><o:p></o:p></p>
<p class="xxxmsonormal"><span style="font-family:"Arial",sans-serif;color:#00664F">Chief of Diagnostic Medical Physics</span><o:p></o:p></p>
<p class="xxxmsonormal" style="margin-bottom:12.0pt"><span style="font-family:"Arial",sans-serif;color:#00664F">Associate Professor of Radiology</span><o:p></o:p></p>
<p class="xxxmsonormal"><span style="font-family:"Arial",sans-serif;color:#00664F">Tel (603) 650-3796<br>
Dartmouth-Health.org</span><o:p></o:p></p>
<p class="xxxmsonormal" style="margin-top:12.0pt"><a href="https://urldefense.com/v3/__https:/www.dartmouth-health.org/__;!!KGKeukY!2BMW4djsl7LXDAsQP936Qdzwr_YKg1h0l_kriJsSkyF7oufIrZiymtwpUxcw_3OatOTY0fNJNQSZ3B2_wV_rIGFyKD6iM202yv9vYKvmJbu4NciqPtp8Yg$"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#7F7F7F;text-decoration:none"><img border="0" width="211" height="60" style="width:2.1979in;height:.625in" id="x_x_x_Picture_x0020_15" src="cid:image012.jpg@01DD1532.11F993E0"></span></a><o:p></o:p></p>
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