{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T02:17:12Z","timestamp":1778638632187,"version":"3.51.4"},"reference-count":48,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,11,10]],"date-time":"2021-11-10T00:00:00Z","timestamp":1636502400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Information"],"abstract":"<jats:p>A growing body of research in retinal imaging is recently considering vascular tortuosity measures or indexes, with definitions and methods mostly derived from cardiovascular research. However, retinal microvasculature has its own peculiarities that must be considered in order to produce reliable measurements. This study analyzed and compared various derived metrics (e.g., TI, TI_avg, TI*CV) across four existing computational workflows. Specifically, the implementation of the models on two critical OCT images highlighted main pitfalls of the methods, which may fail in reliably differentiating a highly tortuous image from a normal one. A tentative, encouraging approach to mitigate the issue on the same OCT exemplificative images is described in the paper, based on the suggested index TI*CV.<\/jats:p>","DOI":"10.3390\/info12110466","type":"journal-article","created":{"date-parts":[[2021,11,11]],"date-time":"2021-11-11T23:02:41Z","timestamp":1636671761000},"page":"466","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Tortuosity Index Calculations in Retinal Images: Some Criticalities Arising from Commonly Used Approaches"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6963-8331","authenticated-orcid":false,"given":"Francesco","family":"Martelli","sequence":"first","affiliation":[{"name":"Department of Cardiovascular, Endocrine-Metabolic Diseases and Aging, Istituto Superiore di Sanit\u00e0, 00161 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6950-4934","authenticated-orcid":false,"given":"Claudia","family":"Giacomozzi","sequence":"additional","affiliation":[{"name":"Department of Cardiovascular, Endocrine-Metabolic Diseases and Aging, Istituto Superiore di Sanit\u00e0, 00161 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1016\/j.preteyeres.2017.07.002","article-title":"Optical Coherence Tomography Angiography: A Comprehensive Review of Current Methods and Clinical Applications","volume":"60","author":"Kashani","year":"2017","journal-title":"Prog. 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