Centrifugal fundus abnormalities in pseudoxanthoma elasticum

Abstract

Purpose: To investigate the Bruch's membrane-retinal pigment epithelium (RPE) complex in pseudoxanthoma elasticum (PXE) by imaging techniques capable of visualizing deep retinal structures with high contrast.

Design: Prospective cross-sectional study.

Participants: Patients with PXE, confirmed by mutation analysis, skin histopathologic examination, or both.

Methods: Sixteen patients were investigated by indocyanine green (ICG) and fluorescein angiography, confocal near-infrared (NIR) reflectance, and fundus autofluorescence imaging using a confocal scanning laser ophthalmoscope (Spectralis HRA-OCT; Heidelberg Engineering, Heidelberg, Germany). Composite digital fundus photography also was performed.

Main outcome measures: Characterization and topographic distribution of abnormalities detected by retinal imaging.

Results: On late-phase ICG angiography, a central area of decreased fluorescence centered on the posterior pole was a characteristic finding in all patients. A second area characterized by increased fundus reflectivity on NIR reflectance imaging extended further into the periphery. A third and most eccentric area showed neither decreased ICG fluorescence nor increased fundus reflectivity. These 3 areas were separated by 2 transition zones, the second being the equivalent of peau d'orange. Angioid streaks did not extend into the third area.

Conclusions: The abnormalities detected by this multimodal imaging approach suggest a centrifugal spread of the retinal pathologic features of the Bruch's membrane-RPE complex in PXE. Decreased fluorescence on late-phase ICG angiography is a consistent sign of retinal pathologic features in PXE. Bruch's membrane calcification may be the underlying cause for the increased reflectivity observed on NIR reflectance imaging.

Financial disclosure(s): Proprietary or commercial disclosure may be found after the references.