Choroidal Thinning in Pseudoexfoliation Syndrome Detected by Enhanced Depth Imaging Optical Coherence Tomography

To measure macular choroidal thickness in normal eyes at different points using enhanced depth imaging (EDI) optical coherence tomography (OCT) and to evaluate the association of choroidal thickness and age. Retrospective, observational case series. EDI OCT images were obtained in patients without significant retinal or choroidal pathologic features. The images were obtained by positioning a spectral-domain OCT device close enough to the eye to acquire an inverted image. Seven sections were obtained within a 5 x 30-degree area centered at the fovea, with 100 scans averaged for each section. The choroid was measured from the outer border of the retinal pigment epithelium to the inner scleral border at 500-microm intervals of a horizontal section from 3 mm temporal to the fovea to 3 mm nasal to the fovea. Statistical analysis was performed to evaluate variations of choroidal thickness at each location and to correlate choroidal thickness and patient age. The mean age of the 30 patients (54 eyes) was 50.4 years (range, 19 to 85 years), and 14 patients (46.7%) were female. The choroid was thickest underneath the fovea (mean, 287 microm; standard deviation, +/- 76 microm). Choroidal thickness decreased rapidly in the nasal direction and averaged 145 microm (+/- 57 microm) at 3 mm nasal to the fovea. Increasing age was correlated significantly with decreasing choroidal thickness at all points measured. Regression analysis suggested that the subfoveal choroidal thickness decreased by 15.6 microm for each decade of life. Choroidal thickness seems to vary topographically within the posterior pole. The thickness of the choroid showed a negative correlation with age. The decrease in the thickness of the choroid may play a role in the pathophysiologic features of various age-related ocular conditions.

To investigate the changes in macular choroidal thickness in eyes with various stages of diabetic retinopathy, using enhanced depth imaging optical coherence tomography (EDI OCT). Sixty-three consecutive diabetic patients--who presented without diabetic retinopathy (NDR); with diabetic retinopathy (nonproliferative diabetic retinopathy [NPDR]) and no clinically significant macular edema (CSME-); or with NDPR and clinically significant macular edema (CSME+)--underwent EDI OCT. Twenty-one age- and sex-matched healthy subjects (21 eyes) also underwent EDI OCT. A total of 63 eyes of 63 consecutive diabetic patients (26 female [41.2%]; mean age 65 ± 9 years, range 48-83 years) were included in the analysis. Mean best-corrected visual acuity was 0.13 ± 0.25 LogMAR (range 0-1). Mean CMT was 272.5 ± 16.2 μm in 21 NDR eyes, 294.5 ± 23.5 μm in 21 NPDR/CSME- eyes, and 385.6 ± 75.1 μm in 21 NPDR/CSME+ eyes. There was no difference in mean subfoveal choroidal thickness among each diabetic group (238.4 ± 47.9 μm [NDR], 207.0 ± 55.9 μm [NPDR/CSME-], 190.8 ± 48.4 μm [NPDR/CSME+]; P = 0.23). The mean subfoveal choroidal thickness was significantly reduced in each diabetic group compared with the control group (309.8 ± 58.5 μm, P < 0.001). In diabetic eyes, there is an overall thinning of the choroid on EDI OCT. A decreased choroidal thickness may lead to tissue hypoxia and consequently increase the level of VEGF, resulting in the breakdown of the blood-retinal barrier and development of macular edema.

The pseudoexfoliation syndrome has recently been suggested to represent the local manifestation of a more widespread disorder. In this study, a case of classic bilateral pseudoexfoliation syndrome with systemic distribution of pseudoexfoliation material involving a variety of organ systems is described. Using transmission electron microscopy, typical pseudoexfoliation fibers were identified in autopsy tissue specimens of skin, heart, lungs, liver, kidney, and cerebral meninges in addition to the classic intraocular locations. The pseudoexfoliation material was mainly localized to connective-tissue portions or septa traversing the various organs. The pseudoexfoliation fibers were consistently associated with connective-tissue components, particularly fibroblasts and collagen and elastic fibers; myocardial tissue specimens; and heart-muscle cells. These findings provide evidence for the systemic nature of the pseudoexfoliation syndrome, which apparently involves an aberrant connective-tissue metabolism throughout the body.