{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,16]],"date-time":"2026-03-16T08:53:20Z","timestamp":1773651200316,"version":"3.50.1"},"reference-count":43,"publisher":"PeerJ","license":[{"start":{"date-parts":[[2026,3,16]],"date-time":"2026-03-16T00:00:00Z","timestamp":1773619200000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>To compare macular and choroidal findings in patients with diabetic peripheral neuropathy but no diabetic retinopathy with healthy patients.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Method<\/jats:title>\n                    <jats:p>We compared the ganglion cell-inner plexiform layer (GCIPL), retinal nerve fiber layer (RNFL), central macular thickness (CMT), subfoveal choroidal thickness (SFCT) and choroidal vascular index (CVI) measurements in patients with diabetic peripheral neuropathy (DPN) without diabetic retinopathy (DR) with healthy individuals.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Mean CMT, RNFL and SFCT values were compared in the study and control groups. There was no statistically significant difference between the groups (\n                      <jats:italic>p<\/jats:italic>\n                      = 0.139, 0.372, and 0.594, respectively). The mean, minimum, superonasal, superior, superotemporal, inferotemporal, inferior and inferonasal GCIPL values were compared in the study group. Only the inferior and inferonasal sectors showed a significant difference (\n                      <jats:italic>p<\/jats:italic>\n                      = 0.012 and 0.023, respectively), while no difference was found in the other sectors (\n                      <jats:italic>p<\/jats:italic>\n                      &gt; 0.05). Mean stromal area (SA), luminal area (LA) and total choroidal area (TCA) values were compared in the study and control groups. While a significant difference was found between the study and control groups in LA and TCA (\n                      <jats:italic>p<\/jats:italic>\n                      = 0.009 and\n                      <jats:italic>p<\/jats:italic>\n                      = 0.008, respectively), no significant difference was found in SA (\n                      <jats:italic>p<\/jats:italic>\n                      = 0.121). The CVI was 0.68850 in the study group and 0.68575 in the control group, and no significant difference was found between the groups (\n                      <jats:italic>p<\/jats:italic>\n                      = 0.456).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>The results obtained demonstrated a statistically significant increase in LA and TCA in the study group, although CVI remained constant. Furthermore, a statistically significant decrease in GCIPL thickness in the inferior and inferonasal sectors of the study group was identified.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.7717\/peerj.20662","type":"journal-article","created":{"date-parts":[[2026,3,16]],"date-time":"2026-03-16T08:05:45Z","timestamp":1773648345000},"page":"e20662","source":"Crossref","is-referenced-by-count":0,"title":["Retrospective evaluation of choroidal and retinal changes in patients with diabetic peripheral neuropathy but no diabetic 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