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<p class="MsoNormal"><span style="font-size:11.0pt">It appears to me that the JC requirement only states that spatial accuracy must be “evaluated,” but, in typical JC fashion, it does not define what that means or how it should be assessed. The good part of
that is that you get to define what that means and of course document what you are doing to meet that requirement.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">I believe a visual assessment using one of the standard test patterns could be reasonably defended. We know what the SMPTE, TG-18, and TG-270 patterns are supposed to look like, and one could document that
no warping or other spatial distortion is present in the displayed objects, thereby demonstrating that spatial accuracy was evaluated.
<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">While measurements are probably preferable and more closely aligned with the applicable AAPM reports, I do not read the JC requirement as making them strictly necessary.
<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">All the best,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Kevin W<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal" style="line-height:115%;background:white"><span style="font-size:9.0pt;line-height:115%;font-family:"Arial",sans-serif;color:#333333"><img width="224" height="45" style="width:2.3333in;height:.4687in" id="Picture_x0020_1" src="cid:image001.png@01DD4B41.CB16A800" alt="The Ohio State University"><span style="mso-ligatures:standardcontextual"><br>
</span></span><b><span style="font-size:11.0pt;line-height:115%;font-family:"Times New Roman",serif;color:#BB0000;background:white;mso-ligatures:standardcontextual">Kevin Wunderle, PhD, FAAPM, FACR</span></b><span style="font-size:11.0pt;line-height:115%;font-family:"Times New Roman",serif;color:#333333;mso-ligatures:standardcontextual"><br>
Professor, Department of Radiology<o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:115%;background:white"><span style="font-size:11.0pt;line-height:115%;font-family:"Times New Roman",serif;color:#333333;mso-ligatures:standardcontextual">Diagnostic Medical Physicist<br>
395 W. 12th Avenue,<o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:115%;background:white"><span style="font-size:11.0pt;line-height:115%;font-family:"Times New Roman",serif;color:#333333;mso-ligatures:standardcontextual">Floor 4, Room 410<o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:115%;background:white"><span style="font-size:11.0pt;line-height:115%;font-family:"Times New Roman",serif;color:#333333;mso-ligatures:standardcontextual">Columbus, OH, 43210<br>
216-245-5513 Mobile<br>
<a href="mailto:kevin.wunderle@osumc.edu"><span style="background:white">kevin.wunderle@osumc.edu</span></a><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+kevin.wunderle=osumc.edu@lists.osu.edu>
<b>On Behalf Of </b>Douglas Pfeiffer via Intl_dxmedphys_wd_osu_list<br>
<b>Sent:</b> Wednesday, September 23, 2026 9:41 AM<br>
<b>To:</b> Little, Kevin <Kevin.Little@osumc.edu><br>
<b>Cc:</b> DxMedPhys List <intl_dxmedphys_wd_osu_list@lists.osu.edu><br>
<b>Subject:</b> Re: [Intl_DxMedPhys] TJC acquisition monitor requirements<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">I guess I have to question how important this is, in the grand scheme. If the internal calipers are correct, does the aspect ratio being off impact anything? Yes,
we do the measurement, and that is a reasonable interpretation of this TJC requirement,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt">I guess I have to question how important this is, in the grand scheme. If the internal calipers are correct, does the aspect ratio being off impact anything? Yes, we do the measurement, and that is a reasonable
interpretation of this TJC requirement, but I can’t help but wonder why this one matters much. I’m happy to be educated if I’m missing something!<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Best regards,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Doug<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Douglas Pfeiffer, MS, DABR FACR, FAAPM (he/him)<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Medical Physicist, Radiation Safety Officer<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Boulder Community Health<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><a href="mailto:xraydoug@me.com">xraydoug@me.com</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;color:black">303.415.7515<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">The opinions expressed in this message are the product of the gray and white matter loitering in my cranium. I speak for myself and no one else, unless I say otherwise.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt">On Sep 23, 2026, at 7:28</span><span style="font-size:12.0pt;font-family:"Arial",sans-serif"> </span><span style="font-size:12.0pt">AM, Little, Kevin <<a href="mailto:Kevin.Little@osumc.edu">Kevin.Little@osumc.edu</a>>
wrote:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt">Hi Doug,</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt">We use the<span class="apple-converted-space"> </span><a href="https://urldefense.com/v3/__https:/aapm.onlinelibrary.wiley.com/doi/10.1118/1.1861159__;!!KGKeukY!zgTSlfKsb3VeeyrH7YQ5-5_CYxfPGVYxiCUSyDaKeqROvWA64QL0YXKJYqkjwzO39wwZjD-GrSycCHo-Z04Nq087KCunfKAN--2l$"><span style="color:#467886">TG-18</span></a><span class="apple-converted-space"> </span>geometric
distortion test. Essentially, we are looking for an incorrect aspect ratio (which we have found, especially for replacement monitors). We use a ruler to measure the same number of squares on the SMPTE or TG-18 QC pattern in both directions. Then we calculate
the percent difference, using the smallest measurement as the reference. TG-18 says that operator’s consoles are secondary displays for everything other than contrast response, so the limit is 5%.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Kevin</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><a name="x__MailAutoSig"><b><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#BB0000;background:white">Kevin J Little, PhD, DABR, DABSNM, CIIP</span></b></a><span style="mso-bookmark:x__MailAutoSig"></span><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#333333"><br>
<span style="background:white">Associate Professor</span><br>
<span style="background:white">Imaging Medical Physics Residency Program Director</span><br>
</span><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#BB0000;background:white">The Ohio State University Wexner Medical Center</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#333333;background:white">Department of Radiology</span><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#333333"><br>
<span style="background:white">395 W 12th Avenue, 4th Fl, Columbus, OH, 43210</span></span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black;background:white"><a href="mailto:ImagingPhysics@osumc.edu">ImagingPhysics@osumc.edu</a></span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#333333;background:white">On-call Physicist:<span class="apple-converted-space"> </span></span><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black;background:white"><a href="https://webxchange.osumc.edu/webxchange/ViewProfile.aspx?profileid=08701">Internal
link</a></span><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#333333;background:white"> or call<span class="apple-converted-space"> </span></span><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black;background:white">614-293-7243,8701#</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span class="apple-converted-space"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> </span></span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Intl_dxmedphys_wd_osu_list
<<a href="mailto:intl_dxmedphys_wd_osu_list-bounces@lists.osu.edu"><span style="color:#467886">intl_dxmedphys_wd_osu_list-bounces@lists.osu.edu</span></a>><span class="apple-converted-space"> </span><b>On Behalf Of<span class="apple-converted-space"> </span></b>Douglas
Pfeiffer via Intl_dxmedphys_wd_osu_list<br>
<b>Sent:</b><span class="apple-converted-space"> </span>Wednesday, September 23, 2026 8:31 AM<br>
<b>To:</b><span class="apple-converted-space"> </span>DxMedPhys List <<a href="mailto:intl_dxmedphys_wd_osu_list@lists.osu.edu"><span style="color:#467886">intl_dxmedphys_wd_osu_list@lists.osu.edu</span></a>><br>
<b>Subject:</b><span class="apple-converted-space"> </span>[Intl_DxMedPhys] TJC acquisition monitor requirements</span><o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:1.0pt;color:white">Good morning! I just received a document to prepare us for upcoming TJC inspections. It includes the following: My question is about the last item - spatial accuracy. I’ve never measured spatial
accuracy on an acquisition display, and I don’t</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Good morning!</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt">I just received a document to prepare us for upcoming TJC inspections. It includes the following:</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><image001.png></span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt">My question is about the last item - spatial accuracy. I’ve never measured spatial accuracy on an acquisition display, and I don’t remember anyone ever talking about it. The only time I could imagine it being
an issue at all is during MR- and CT-guided biopsies, but that is accuracy of the system calipers and not a function of the display. What are folks doing with this one?</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:12.0pt">Best regards,</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Doug</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Douglas Pfeiffer, MS, DABR FACR, FAAPM (he/him)</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Medical Physicist, Radiation Safety Officer</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Boulder Community Health</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><a href="mailto:xraydoug@me.com"><span style="color:#467886">xraydoug@me.com</span></a></span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt">303.415.7515</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:12.0pt">The opinions expressed in this message are the product of the gray and white matter loitering in my cranium. I speak for myself and no one else, unless I say otherwise.</span><o:p></o:p></p>
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