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The purpose of the current study was to determine cross-sectional and longitudinal associations between papilledema severity and retinal vessel tortuosity (RVT) in IIH.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Images from 24 eyes of 15 patients diagnosed with papilledema were acquired at two visits. Papilledema severity was graded by Frisen score (FS). Images were analyzed to determine RVT in arteries and veins within the peripapillary region using the first-order derivative method. Inter-visit differences in FS (\u0394FS) and RVT (\u0394RVT) were calculated. Generalized estimating equation models determined associations of FS and \u0394FS with RVT and \u0394RVT, respectively.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Based on compiled arterial or venous RVT data from both visits, there was no significant association between RVT and FS (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.89), whereas venous RVT (0.31\u2009\u00b1\u20090.02;\n                      <jats:italic>N<\/jats:italic>\n                      \u2009=\u200948) was significantly higher than arterial RVT (0.24\u2009\u00b1\u20090.01;\n                      <jats:italic>N<\/jats:italic>\n                      \u2009=\u200948) (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.03). Compared to the \u0394FS\u2009=\u20090 group, venous \u0394RVT was higher in the \u0394FS\u2009=\u20093 group (\u03b2\u2009=\u20090.05,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.005), while arterial \u0394RVT was higher in \u0394FS\u2009\n                      <jats:italic>\u2265<\/jats:italic>\n                      \u20091 (\u03b2\u2009\n                      <jats:italic>\u2265<\/jats:italic>\n                      \u20090.04; p\u2009\n                      <jats:italic>\u2264<\/jats:italic>\n                      \u20090.04).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>The finding of an association between improvement in papilledema and reduction in RVT shows promise for vessel tortuosity as a biomarker for monitoring disease progression and response to therapeutic interventions, as well as advancing knowledge of retinal vascular changes due to papilledema.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00417-026-07254-9","type":"journal-article","created":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T03:52:28Z","timestamp":1777693948000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Association of papilledema severity with retinal vessel tortuosity in idiopathic intracranial hypertension"],"prefix":"10.1007","author":[{"given":"Yuhang","family":"Zou","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Farzan","family":"Abdolahi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anthony E.","family":"Felder","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Connie","family":"Huang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kimberly K.","family":"Gokoffski","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mahnaz","family":"Shahidi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2026,5,2]]},"reference":[{"key":"7254_CR1","doi-asserted-by":"publisher","first-page":"78","DOI":"10.1001\/archneur.1993.00540010072020","volume":"50","author":"K Radhakrishnan","year":"1993","unstructured":"Radhakrishnan K, Ahlskog JE, Cross SA, Kurland LT, O\u2019Fallon WM (1993) Idiopathic intracranial hypertension (pseudotumor cerebri). 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