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If they're not accounting for the specific patient population, I don't think it is particularly useful. Cancer patients being scanned to monitor treatment response or for adaptive radiotherapy are going to get much higher CED than trauma patients</div>
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If they're not accounting for the specific patient population, I don't think it is particularly useful.</div>
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Cancer patients being scanned to monitor treatment response or for adaptive radiotherapy are going to get much higher CED than trauma patients getting a CT on admission and one follow-up scan 6-24 hours later to monitor for changes. Comparing the RERL for
a large cancer centre with in-house imaging to the DI department at a smaller ER isn't a meaningful comparison.</div>
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I could see it being a potentially useful metric if they're calculating it based on the clinical indication or for equivalent patient populations, but even then I'm not sure how it would offer anything useful over DRLs and number of scans separately, both of
which are more directly actionable. You can reduce the dose per scan or the number of scans, but you can't reduce the CED without doing at least one of the two.</div>
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Devin</div>
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<b>From:</b> Intl_dxmedphys_wd_osu_list <intl_dxmedphys_wd_osu_list-bounces+devin.baillie=cancercarealberta.ca@lists.osu.edu> on behalf of Bill Erwin via Intl_dxmedphys_wd_osu_list <intl_dxmedphys_wd_osu_list@lists.osu.edu><br>
<b>Sent:</b> February 24, 2026 1:39 PM<br>
<b>To:</b> intl_dxmedphys_wd_osu_list@lists.osu.edu <intl_dxmedphys_wd_osu_list@lists.osu.edu><br>
<b>Subject:</b> [Intl_DxMedPhys] Recurrent CT imaging and strategies for patient radiation protection</div>
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Caution - This email came from an external address and may contain unsafe content. Ensure you trust this sender before opening attachments or clicking any links in this message</div>
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An article was just published regarding cumulative CT dose and a so-called recurrent exposure reference level (RERL). (I came across it via AuntMinnie. ) I am thinking there might be some opinions about this amongst the listers. Discussion</div>
<div style="direction: ltr;" class="elementToProof">An article was just published regarding cumulative CT dose and a so-called recurrent exposure reference level (RERL). (I came across it via AuntMinnie.) I am thinking there might be some opinions about this
amongst the listers. Discussion commences ...</div>
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<div style="direction: ltr;" class="elementToProof"><a data-auth="NotApplicable" class="OWAAutoLink" id="OWA636455eb-4c02-0007-9409-da32356cfe5e" href="https://urldefense.com/v3/__https://iopscience.iop.org/article/10.1088/1361-6498/ae4521__;!!KGKeukY!0xsXpnIvIam9SVWOPEGMQWIzdeNEEt19uAjta45VhWA_Y-kAfvKdXOrwOr7_zNNYa6f4ZiK2Xnwy8g8HgOzR8AmGzDtx-cdNNcKVDFCY$">https://iopscience.iop.org/article/10.1088/1361-6498/ae4521</a></div>
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<div style="direction: ltr;" class="elementToProof">Regards,</div>
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