Winegarner Andrew, Oie Yoshinori, Nishida Kohji
Department of Ophthalmology, Osaka University Graduate School of Medicine, Room E7, Yamadaoka 2-2, Osaka, 565-0871, Japan.
Kansas University Medical Center, School of Medicine, Kansas City, KS, USA.
BMC Ophthalmol. 2018 Apr 13;18(1):92. doi: 10.1186/s12886-018-0757-7.
Pellucid marginal corneal degeneration is a non-inflammatory disorder complicated by severe inferior corneal thinning. The central portion of the cornea, consequently, appears to protrude outwards, decreasing vision by means of an irregular stigmatism. Additionally, acute hydrops can occur in case of Descemet's membrane rupture.
A 41-year-old Japanese woman presenting with severe visual loss in the left eye was examined and observed to have had full thickness corneal perforation as well as a Descemet membrane rupture with massive edema in the corneal stroma. Anterior segment optical coherence tomography-based corneal topography revealed a distorted crab claw sign indicating pellucid marginal corneal degeneration. The Descemet membrane rupture allowed acute hydrops to occur which was especially noteworthy given the scale of edema present within the stroma, rotating 180 degrees along the limbus, causing a smiley-face like lesion. We visualized it via a gonioscopic three-dimensional optical coherence tomography to build a three-dimensional video. Patient history revealed a previous acute hydrops in the right eye as well, which was ultimately treated with anterior lamellar keratoplasty, suggesting the pellucid marginal corneal degeneration had a classic bilateral involvement, which was also characterized with bilateral acute hydrops.
This appears to be a very rare and interesting presentation of bilateral pellucid marginal degeneration, wherein not only acute hydrops formed bilaterally, but the cavity within the cornea stroma was exceptionally large with an unusual shape. Using the gonioscopic three-dimensional optical coherence tomography imaging, we were able to easily visualize the massive intrastromal cavern, and appropriately planned the crescent-shaped anterior lamellar keratoplasty. The 3d video constructed using this data is particularly elucidative compared to 2d images. As such, we recommend utilizing 3d imaging in cases where more conventional topography is not as explanatory with respect to precise nature of deformation.
透明边缘角膜变性是一种非炎症性疾病，伴有严重的角膜下部变薄。因此，角膜中央部分似乎向外突出，通过不规则散光降低视力。此外，在Descemet膜破裂的情况下可能会发生急性水肿。
一名41岁的日本女性因左眼严重视力丧失接受检查，发现有全层角膜穿孔以及Descemet膜破裂，角膜基质有大量水肿。基于前节光学相干断层扫描的角膜地形图显示出扭曲的蟹爪征，提示透明边缘角膜变性。Descemet膜破裂导致急性水肿发生，鉴于基质内水肿的范围，沿角膜缘旋转180度，形成类似笑脸的病变，这一点尤其值得注意。我们通过前房角镜三维光学相干断层扫描对其进行可视化，以构建三维视频。患者病史显示右眼之前也发生过急性水肿，最终接受了前板层角膜移植术，提示透明边缘角膜变性具有典型的双侧受累，且伴有双侧急性水肿。
这似乎是双侧透明边缘变性一种非常罕见且有趣的表现，其中不仅双侧形成急性水肿，而且角膜基质内的腔隙异常大且形状异常。使用前房角镜三维光学相干断层扫描成像，我们能够轻松地可视化基质内的巨大腔隙，并适当规划了新月形前板层角膜移植术。与二维图像相比，利用这些数据构建的三维视频特别具有说明性。因此，我们建议在更传统的地形图对变形的精确性质解释不足的情况下使用三维成像。
