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[Clinical observation of posterior polymorphous corneal dystrophy].

OBJECTIVE
To research the clinical features and in vivo confocal microscopic findings of posterior polymorphous corneal dystrophy (PPCD).


METHODS
It was a retrospective consecutive case study. Ten patients with PPCD, attended at Optometry Department of Henan Eye Institute from March 2007 to August 2009, were analyzed. All the subjects were examined by slit-lamp, OrbscanII, specular microscopy, HRT3/RCM confocal microscopy. Mann-Whitney U test was used to analysis the data.


RESULTS
The age of the patients ranged from 8 to 35 years. Seven eyes of the 4 patients have the vesicular lesions, five eyes of the 5 patients were band lesions and 1 patient had bilateral diffused opacities, this patient also had iridocorneal adhesions with associated papillary ectropion but without glaucoma. In total, 14 eyes of the 10 patients had PPCD. Two eyes had abnormal OrbscanII topography, it showed both anterior and posterior surface protrusion. Specular microscopy exam indicated large cells in size and reduced endothelium density. The mean size of the affected eye was 584 µm(2), the normal eye was 316 µm(2). The difference was statistically significant (U = 0.000, P = 0.002). The density of the endothelium was 1746 cells/mm(2) in affected eye and 3201 cells/mm(2) in normal eye. The difference was also statistically significant (U = 0.000, P = 0.002). In vivo confocal microscopy showed endothelial polymorphism. Occasional bright endothelial nuclei were seen. A variety of curvilinear and vesicular abnormalities were imaged including orange or finger like lesion, round or oval dark area with hyper reflectivity border. Some large lesions may lose endothelium with rough surface have a dike appearance.


CONCLUSIONS
Careful exam by slit-lamp may help to diagnose PPCD and further specular microscopy and(or) in vivo confocal microscopy exam will confirm it. Some cases may have abnormal topography, or associated with high intraocular pressure.