In vivo confocal microscopy of posterior polymorphous dystrophy.

Purpose: This study was designed to delineate the morphologic features of posterior polymorphous dystrophy (PPD) using in vivo confocal microscopy.

Methods: Six patients with clinically diagnosed PPD were examined by slit-lamp biomicroscopy, Orbscan II slit-scanning elevation topography, and in vivo confocal microscopy.

Results: Endothelial cell densities ranged from 613 to 3,405 cells/mm and endothelial polymegathism was noted in all cases, whereas endothelial pleomorphism was not a prominent feature. Three cases exhibited bright endothelial nuclei. A variety of abnormal curvilinear and vesicular abnormalities were imaged by in vivo confocal microscopy, with lesions ranging between 6 and 159 microm in diameter. Abnormal endothelial cells were visible within some of these lesions. Six cases showed hyperreflectivity at the level of Descemet's membrane around the lesions. Deep stromal keratocytes appeared to aggregate around, or were compressed by, the endothelial lesions in one case.

Conclusions: We report the largest case series of PPD imaged by in vivo confocal microscopy. The ability of in vivo confocal microscopy to assess the living cornea over time enables monitoring of disease progression and thus the potential to identify and correlate development of, or changes in, microstructural features. As more data become available, these analyses may enable the formulation of prognostic and diagnostic criteria.