Choroidal thickness in polypoidal choroidal vasculopathy and exudative age-related macular degeneration.

PURPOSE: To compare choroidal thickness between eyes with polypoidal choroidal vasculopathy (PCV) and eyes with age-related macular degeneration (AMD).

DESIGN

Observational, comparative case series.

PARTICIPANTS

Twenty-five eyes with PCV, 14 uninvolved fellow eyes with PCV, 30 eyes with exudative AMD, 17 eyes with early AMD, and 20 eyes of age-matched normal subjects.

METHODS

Choroidal thickness was measured using enhanced-depth imaging optical coherence tomography. Subfoveal choroidal thickness in each eye was analyzed by measurement of the vertical distance from the Bruch's membrane to the innermost scleral layer. Nasal, superior, temporal, and inferior choroidal thicknesses, 1500 μm apart from the foveal center, were also evaluated in all eyes.

MAIN OUTCOME MEASURES: Choroidal thickness in each group.

RESULTS

Mean (± standard deviation) subfoveal choroidal thickness in eyes with PCV and in their uninvolved fellow eyes was 438.3±87.8 μm and 372.9±112.0 μm, respectively, which was significantly greater than in eyes of age-matched normal subjects (224.8±52.9 μm) (P<0.001 and P = 0.003, respectively). Subfoveal choroidal thickness of eyes with exudative AMD (171.2±38.5 μm) and eyes with early AMD (177.4±49.7 μm) was thinner than that of age-matched normal subjects (P = 0.004 and P = 0.078, respectively). Choroidal thickness at each of the other 4 points showed a similar tendency.

CONCLUSIONS

This study demonstrates thickening of choroid in the eyes with PCV, in contrast with choroidal thinning observed in eyes with AMD. These findings suggest involvement of different pathogenic mechanisms in PCV from those in exudative AMD.