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Recent advances in optical coherence tomography angiography have enabled noninvasive visualization of the vasculature around the optic disc. In this study, we investigated the clinical features of young Korean patients with OAG and compared the peripapillary vessel density of patients with normal-tension glaucoma (NTG) to those with high-tension glaucoma (HTG). The peripapillary vessel density was reduced in eyes with HTG compared with that in normal subjects (HTG: 23.18\u2009\u00b1\u20092.06% vs. normal subjects: 24.74\u2009\u00b1\u20091.88%, <jats:italic>P<\/jats:italic> value\u2009=\u20090.013). In contrast, the peripapillary vessel density of eyes with NTG was comparable with that of normal eyes (NTG: 23.98\u2009\u00b1\u20092.30% vs. normal subjects: 24.74\u2009\u00b1\u20091.88%, <jats:italic>P<\/jats:italic> value\u2009=\u20090.505). These findings suggest that young patients with HTG show greater peripapillary microvascular attenuation than healthy subjects or young patients with NTG, indicating that different levels of the initial untreated IOP may have different effects on the peripapillary vessel density in young patients with OAG.<\/jats:p>","DOI":"10.1038\/s41598-019-55707-5","type":"journal-article","created":{"date-parts":[[2019,12,16]],"date-time":"2019-12-16T11:03:32Z","timestamp":1576494212000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Peripapillary Vessel Density in Young Patients with Open-Angle Glaucoma: Comparison between High-Tension and Normal-Tension Glaucoma"],"prefix":"10.1038","volume":"9","author":[{"given":"Ji-Hye","family":"Park","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chungkwon","family":"Yoo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yong Yeon","family":"Kim","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2019,12,16]]},"reference":[{"key":"55707_CR1","doi-asserted-by":"publisher","first-page":"1711","DOI":"10.1016\/S0140-6736(04)16257-0","volume":"363","author":"RN Weinreb","year":"2004","unstructured":"Weinreb, R. 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