{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T11:36:07Z","timestamp":1785411367621,"version":"3.56.0"},"reference-count":22,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T00:00:00Z","timestamp":1776124800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"crossref","award":["RS-2024-00335770"],"award-info":[{"award-number":["RS-2024-00335770"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"crossref"}]},{"award":["RS-2024-00335770"],"award-info":[{"award-number":["RS-2024-00335770"]}],"id":[{"id":"https:\/\/ror.org\/013aysd81","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Korea Hydro & Nuclear Power Co. Ltd","award":["A21IP11"],"award-info":[{"award-number":["A21IP11"]}]},{"award":["A21IP11"],"award-info":[{"award-number":["A21IP11"]}],"id":[{"id":"https:\/\/ror.org\/00twdhr48","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Purpose: No prior clinical studies have quantitatively evaluated the effect of low-dose radiation therapy (LDRT) on Alzheimer\u2019s disease (AD) brain changes using multi-modal MRI. This study examined the feasibility of using conductivity, diffusion, and brain tissue volume measures to detect treatment effects in patients with AD receiving LDRT. Methods: Nine patients with mild AD were enrolled in three groups. Three patients in each group were assigned to the control group (0 cGy) and the treated groups [24 cGy\/6 fractions (4 cGy for each fraction) and 300 cGy\/6 fractions (50 cGy for each fraction)]. Conductivity, diffusivity, and brain tissue volume were acquired at baseline and 6 months post-treatment and were evaluated to assess within-group MRI changes and evaluate associations between MRI measures and Mini-Mental State Examination (MMSE) scores. Results: Region-of-interest (ROI) analyses identified substantial changes in high-frequency conductivity (HFC) (e.g., left insula), cerebrospinal fluid (CSF) volumes (e.g., anterior cingulate, limbic regions), and diffusion tensor imaging (DTI) metrics, such as axial diffusivity (AxD) and fractional anisotropy (FA), in fusiform, thalamic, hippocampal, and occipital areas. Correlation analysis showed strong associations between MRI measures and cognition, most notably HFC in the left fusiform gyrus (r = 0.843, p = 0.0043) after treatment. Diffusion indices across multiple regions also showed significant positive or negative correlations with MMSE. Conclusions: This exploratory clinical study demonstrates that LDRT induces measurable physiological and microstructural alterations in the brain detectable via conductivity and diffusion MRI. Conductivity emerged as the sensitive biomarker, showing strong cognitive correlations. These exploratory findings suggest that multi-modal quantitative MRI can serve as an effective tool for evaluating treatment response in clinical LDRT for AD.<\/jats:p>","DOI":"10.3390\/diagnostics16081163","type":"journal-article","created":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T14:24:58Z","timestamp":1776176698000},"page":"1163","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Evaluation of Low-Dose Radiation Treatment Effects Using Conductivity, Diffusivity, and Brain Tissue Volumes Treated in Patients with Mild Alzheimer\u2019s Disease: Exploratory Investigation"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8158-4700","authenticated-orcid":false,"given":"Weon Kuu","family":"Chung","sequence":"first","affiliation":[{"name":"Department of Radiation Oncology, Kyung Hee University Hospital at Gangdong, Kyung Hee University College of Medicine, Seoul 05278, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-3218-0849","authenticated-orcid":false,"given":"Hwang Mi","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, College of Electronics and Information, Kyung Hee University, Gyeonggi-do 17104, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mun Bae","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Mathematics, College of Basic Science, Konkuk University, Seoul 05029, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8387-9476","authenticated-orcid":false,"given":"Kisoo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, College of Electronics and Information, Kyung Hee University, Gyeonggi-do 17104, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oh-In","family":"Kwon","sequence":"additional","affiliation":[{"name":"Department of Mathematics, College of Basic Science, Konkuk University, Seoul 05029, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3838-8739","authenticated-orcid":false,"given":"Ye Jin","family":"Yoo","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Kyung Hee University Hospital at Gangdong, Kyung Hee University College of Medicine, Seoul 05278, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3016-2591","authenticated-orcid":false,"given":"Hak Young","family":"Rhee","sequence":"additional","affiliation":[{"name":"Department of Neurology, Kyung Hee University Hospital at Gangdong, Kyung Hee University College of Medicine, Seoul 05278, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8881-1884","authenticated-orcid":false,"given":"Geon-Ho","family":"Jahng","sequence":"additional","affiliation":[{"name":"Department of Radiology, Kyung Hee University Hospital at Gangdong, Kyung Hee University College of Medicine, Seoul 05278, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"329","DOI":"10.1056\/NEJMra0909142","article-title":"Alzheimer\u2019s disease","volume":"362","author":"Querfurth","year":"2010","journal-title":"N. 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