Chan W K, Weissman B A
Department of Ophthalmology, Jules Stein Eye Institute, UCLA School of Medicine, CA 90095-7003, USA.
Am J Ophthalmol. 1996 May;121(5):540-6. doi: 10.1016/s0002-9394(14)75428-5.
To determine whether contact lens, related corneal pannus regressed when eyes were refitted with rigid gas-permeable contact lenses and to investigate the role of hypoxia as the putative origin of this complication.
Twenty-three eyes of 14 patients with corneal pannus were identified retrospectively from a referral practice population and were separated into two subgroups. One subgroup accepted refitting with rigid gas-permeable contact lenses or discontinued contact lens wear, and the other elected to continue wearing hydrogel or polymethylmethacrylate contact lenses. The response of pannus was observed by slit-lamp biomicroscopy and photographs and was compared between the two subgroups. One eye of each of six patients identified with bilateral corneal pannus secondary to daily wear of hydrogel contact lenses was selected at random. Duplicates of the hydrogel contact lenses worn by these eyes were obtained, and their peripheral oxygen transmissibility (Dk/Lp) values were compared with those of a control group of hydrogel contact lenses identical to those worn by another group of patients, matched by age, gender, and laterality to the study group, but who did not have corneal vascularization.
Vascularization regressed in 14 eyes of nine patients refitted with rigid gas-permeable contact lenses and also in both eyes of one patient who discontinued contact lens wear. All seven eyes of five patients who declined refitting showed persistence or increase of pannus. The mean Dk/Lp of the hydrogel contact lenses for six eyes with pannus was 3.8 X 10(-9) cm ml O2/s ml mm Hg; mean Dk/Lp was 8.6 X 10(-9) cm ml O2/s ml mm Hg for the lens of the control eyes. This difference was found to be statistically significant (P = .028).
Peripheral, contact lens-induced hypoxia is a risk factor for corneal pannus, and conversion from hydrogel or polymethylmethacrylate contact lenses to daily wear rigid gas-permeable contact lenses in these eyes successfully reversed this complication.
确定当眼睛重新佩戴硬性透气性隐形眼镜时，与隐形眼镜相关的角膜血管翳是否会消退，并研究缺氧作为这种并发症假定起源的作用。
从转诊患者群体中回顾性识别出14例患有角膜血管翳患者的23只眼睛，并将其分为两个亚组。一个亚组接受重新佩戴硬性透气性隐形眼镜或停止佩戴隐形眼镜，另一个亚组选择继续佩戴水凝胶或聚甲基丙烯酸甲酯隐形眼镜。通过裂隙灯生物显微镜检查和拍照观察血管翳的反应，并在两个亚组之间进行比较。随机选择6例因每日佩戴水凝胶隐形眼镜继发双侧角膜血管翳患者中的每例患者的一只眼睛。获取这些眼睛所佩戴水凝胶隐形眼镜的复制品，并将其周边氧气透过率（Dk/Lp）值与对照组水凝胶隐形眼镜的Dk/Lp值进行比较，对照组水凝胶隐形眼镜与另一组患者所佩戴的相同，按年龄、性别和眼别与研究组匹配，但没有角膜血管化。
9例重新佩戴硬性透气性隐形眼镜患者的14只眼睛以及1例停止佩戴隐形眼镜患者的两只眼睛中的血管化均消退。5例拒绝重新佩戴的患者的所有7只眼睛显示血管翳持续存在或加重。6只患有血管翳眼睛的水凝胶隐形眼镜的平均Dk/Lp为3.8×10⁻⁹ cm·ml O₂/s·ml·mmHg；对照眼镜片的平均Dk/Lp为8.6×10⁻⁹ cm·ml O₂/s·ml·mmHg。发现这种差异具有统计学意义（P = 0.028）。
周边的、隐形眼镜引起的缺氧是角膜血管翳的一个危险因素，在这些眼睛中从水凝胶或聚甲基丙烯酸甲酯隐形眼镜转换为每日佩戴硬性透气性隐形眼镜成功逆转了这种并发症。
