Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital.
Department of Ophthalmology, Bundang Jesaeng General Hospital, Daejin Medical Center, Seongnam, Korea.
J Glaucoma. 2020 Jan;29(1):39-45. doi: 10.1097/IJG.0000000000001408.
Parapapillary choroidal microvasculature dropout (MvD), as observed by optical coherence tomography (OCT) angiography, was useful to detect glaucomatous damage in highly myopic eyes with unreliable OCT results due to segmentation errors.
The purpose of this study was to evaluate the usefulness of optical coherence tomography angiography (OCTA) imaging of the peripapillary choroidal microvasculature in detecting glaucomatous damage in highly myopic eyes, in cases where evaluating the thickness of the retinal nerve fiber layer (RNFL) is unreliable due to OCT segmentation errors.
Forty-five highly myopic eyes with primary open-angle glaucoma (POAG) with an axial length >26.5 mm, and 15 age-matched and axial length-matched 15 control eyes were included in this cross-sectional observational study. All participants had a segmentation error in OCT circumpapillary RNFL scanning. The peripapillary choroidal microvasculature was evaluated on en-face images obtained using swept-source OCTA. MvD was defined as a focal sectoral capillary dropout with no visible microvascular network identified in the choroidal layer. The topographic correlation between the MvD and a hemifield visual field (VF) defect was assessed using κ statistics. The MvD size was assessed by measuring both its area and circumferential extent.
Choroidal MvD was observed in 44 of the 45 (97.8%) POAG eyes with high myopia, while none of the control eyes showed a choroidal MvD. There was an excellent topographic relationship between the choroidal MvD and the hemifield VF defect (κ=0.863, P<0.001). The area (R=0.2619, P=0.0006) and circumferential extent (R=0.3088, P=0.0002) of the MvD have significantly associated with the VF mean deviation.
Choroidal MvDs were observed in most of the highly myopic POAG eyes and were topographically correlated with the location of glaucomatous VF defects despite unreliable OCT RNFL thickness measurements. Using OCTA to investigate the choroidal microvasculature may facilitate diagnoses of glaucoma in highly myopic eyes.
光学相干断层扫描血管造影（OCTA）观察到的视盘旁脉络膜微血管缺失（MvD），在由于分段错误而导致 OCT 结果不可靠的高度近视眼中，有助于检测青光眼损害。
本研究旨在评估在由于 OCT 分段错误而导致视网膜神经纤维层（RNFL）厚度评估不可靠的情况下，使用 OCTA 对视盘周围脉络膜微血管成像检测高度近视性青光眼（POAG）患者青光眼损害的有用性。
这项横断面观察性研究纳入了 45 只轴向长度大于 26.5mm 的高度近视性 POAG 眼和 15 只年龄匹配和轴向长度匹配的 15 只对照眼。所有参与者的 OCT 环周 RNFL 扫描均存在分段错误。在使用扫频源 OCTA 获得的共焦图像上评估视盘周围脉络膜微血管。MvD 定义为脉络膜层中没有可见微血管网络的局灶性扇形毛细血管缺失。使用κ统计评估 MvD 与视野（VF）缺损的半视野之间的地形相关性。通过测量其面积和周长来评估 MvD 的大小。
45 只高度近视性 POAG 眼中有 44 只（97.8%）观察到脉络膜 MvD，而对照组的 15 只眼中均未观察到脉络膜 MvD。脉络膜 MvD 与半视野 VF 缺损之间存在极好的地形关系（κ=0.863，P<0.001）。MvD 的面积（R=0.2619，P=0.0006）和周长（R=0.3088，P=0.0002）与 VF 平均偏差显著相关。
尽管 OCT RNFL 厚度测量不可靠，但在大多数高度近视性 POAG 眼中观察到脉络膜 MvD，并且与青光眼 VF 缺损的位置具有地形相关性。使用 OCTA 研究脉络膜微血管可能有助于诊断高度近视眼的青光眼。
