Jessica Westwood, India Mayhook-Walker, Ciaran Simpkins, Andrew Darby-Smith, Dan Morris, Eduardo Normando
{"title":"视网膜血管对缺氧反应的改变:一项高海拔探险研究。","authors":"Jessica Westwood, India Mayhook-Walker, Ciaran Simpkins, Andrew Darby-Smith, Dan Morris, Eduardo Normando","doi":"10.1089/ham.2023.0084","DOIUrl":null,"url":null,"abstract":"<p><p>Westwood, Jessica, India Mayhook-Walker, Ciaran Simpkins, Andrew Darby-Smith, Dan Morris, and Eduardo Normando. Retinal vascular changes in response to hypoxia: a high-altitude expedition study. <i>High Alt Med Biol</i>. 25:49-59, 2024. <b><i>Background:</i></b> Increased tortuosity and engorgement of retinal vasculature are recognized physiological responses to hypoxia. This can lead to high-altitude retinopathy (HAR), but incidence reports are highly variable, and our understanding of the etiological mechanisms remains incomplete. This study quantitatively evaluated retinal vascular changes during an expedition to 4,167 m. <b><i>Methods:</i></b> Ten healthy participants summited Mount Toubkal, Morocco. Fundus images were taken predeparture, daily throughout the expedition, and 1 month postreturn. Diameter and tortuosity of four vessels were assessed, in addition to vessel density and features of HAR. <b><i>Results:</i></b> Significant (<i>p</i> ≤ 0.05) increases in tortuosity and diameter were observed in several vessels on high-altitude exposure days. There was a strong correlation between altitude and supratemporal retinal artery diameter on days 2, 3, and 6 of the expedition (<i>r</i> = 0.7707, 0.7951, 0.7401, respectively; <i>p</i> < 0.05). There was a significant increase in median vessel density from 6.7% at baseline to 10.0% on summit day. Notably there were no incidences of HAR. <b><i>Conclusion:</i></b> Physiological but not pathological changes were seen in this cohort, which gives insight into the state of the cerebral vasculature throughout this expedition. These results are likely attributable to relatively low altitude exposure, a conservative ascent profile, and the cohort's demographic. Future study must include daily retinal images at higher altitudes and take steps to mitigate environmental confounders. This study is relevant to altitude tourists, patients with diabetic retinopathy or retinal vein occlusion, and critically ill patients.</p>","PeriodicalId":12975,"journal":{"name":"High altitude medicine & biology","volume":null,"pages":null},"PeriodicalIF":1.6000,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Retinal Vascular Changes in Response to Hypoxia: A High-Altitude Expedition Study.\",\"authors\":\"Jessica Westwood, India Mayhook-Walker, Ciaran Simpkins, Andrew Darby-Smith, Dan Morris, Eduardo Normando\",\"doi\":\"10.1089/ham.2023.0084\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Westwood, Jessica, India Mayhook-Walker, Ciaran Simpkins, Andrew Darby-Smith, Dan Morris, and Eduardo Normando. Retinal vascular changes in response to hypoxia: a high-altitude expedition study. <i>High Alt Med Biol</i>. 25:49-59, 2024. <b><i>Background:</i></b> Increased tortuosity and engorgement of retinal vasculature are recognized physiological responses to hypoxia. This can lead to high-altitude retinopathy (HAR), but incidence reports are highly variable, and our understanding of the etiological mechanisms remains incomplete. This study quantitatively evaluated retinal vascular changes during an expedition to 4,167 m. <b><i>Methods:</i></b> Ten healthy participants summited Mount Toubkal, Morocco. Fundus images were taken predeparture, daily throughout the expedition, and 1 month postreturn. Diameter and tortuosity of four vessels were assessed, in addition to vessel density and features of HAR. <b><i>Results:</i></b> Significant (<i>p</i> ≤ 0.05) increases in tortuosity and diameter were observed in several vessels on high-altitude exposure days. There was a strong correlation between altitude and supratemporal retinal artery diameter on days 2, 3, and 6 of the expedition (<i>r</i> = 0.7707, 0.7951, 0.7401, respectively; <i>p</i> < 0.05). There was a significant increase in median vessel density from 6.7% at baseline to 10.0% on summit day. Notably there were no incidences of HAR. <b><i>Conclusion:</i></b> Physiological but not pathological changes were seen in this cohort, which gives insight into the state of the cerebral vasculature throughout this expedition. These results are likely attributable to relatively low altitude exposure, a conservative ascent profile, and the cohort's demographic. Future study must include daily retinal images at higher altitudes and take steps to mitigate environmental confounders. This study is relevant to altitude tourists, patients with diabetic retinopathy or retinal vein occlusion, and critically ill patients.</p>\",\"PeriodicalId\":12975,\"journal\":{\"name\":\"High altitude medicine & biology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.6000,\"publicationDate\":\"2024-03-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"High altitude medicine & biology\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://doi.org/10.1089/ham.2023.0084\",\"RegionNum\":4,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2023/11/23 0:00:00\",\"PubModel\":\"Epub\",\"JCR\":\"Q4\",\"JCRName\":\"BIOPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"High altitude medicine & biology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1089/ham.2023.0084","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2023/11/23 0:00:00","PubModel":"Epub","JCR":"Q4","JCRName":"BIOPHYSICS","Score":null,"Total":0}
Retinal Vascular Changes in Response to Hypoxia: A High-Altitude Expedition Study.
Westwood, Jessica, India Mayhook-Walker, Ciaran Simpkins, Andrew Darby-Smith, Dan Morris, and Eduardo Normando. Retinal vascular changes in response to hypoxia: a high-altitude expedition study. High Alt Med Biol. 25:49-59, 2024. Background: Increased tortuosity and engorgement of retinal vasculature are recognized physiological responses to hypoxia. This can lead to high-altitude retinopathy (HAR), but incidence reports are highly variable, and our understanding of the etiological mechanisms remains incomplete. This study quantitatively evaluated retinal vascular changes during an expedition to 4,167 m. Methods: Ten healthy participants summited Mount Toubkal, Morocco. Fundus images were taken predeparture, daily throughout the expedition, and 1 month postreturn. Diameter and tortuosity of four vessels were assessed, in addition to vessel density and features of HAR. Results: Significant (p ≤ 0.05) increases in tortuosity and diameter were observed in several vessels on high-altitude exposure days. There was a strong correlation between altitude and supratemporal retinal artery diameter on days 2, 3, and 6 of the expedition (r = 0.7707, 0.7951, 0.7401, respectively; p < 0.05). There was a significant increase in median vessel density from 6.7% at baseline to 10.0% on summit day. Notably there were no incidences of HAR. Conclusion: Physiological but not pathological changes were seen in this cohort, which gives insight into the state of the cerebral vasculature throughout this expedition. These results are likely attributable to relatively low altitude exposure, a conservative ascent profile, and the cohort's demographic. Future study must include daily retinal images at higher altitudes and take steps to mitigate environmental confounders. This study is relevant to altitude tourists, patients with diabetic retinopathy or retinal vein occlusion, and critically ill patients.
期刊介绍:
High Altitude Medicine & Biology is the only peer-reviewed journal covering the medical and biological issues that impact human life at high altitudes. The Journal delivers critical findings on the impact of high altitude on lung and heart disease, appetite and weight loss, pulmonary and cerebral edema, hypertension, dehydration, infertility, and other diseases. It covers the full spectrum of high altitude life sciences from pathology to human and animal ecology.