Journal of Clinical and Experimental Ophthalmology
Open Access

Abstract

Focal Temporal Scleral Bulge with Choroidal Thinning: An Under-Recognized Tomographic Feature

Rosa Dolz-Marco, Roberto Gallego-Pinazo, Maria Isabel López-Gálvez, Jose I Tembl, Manuel Díaz-Llopis and Carol Shields

Purpose: To describe the swept source tomographic characteristics of focal temporal scleral bulge with choroidal thinning as a normal variation of the ocular anatomy in healthy eyes.
Methods: Cross-sectional observational study. Swept-source optical coherence tomography (SS-OCT) examinations in healthy patients performed between October and December 2013 were analyzed. The presence of a focal scleral bulge with choroidal thickness (CT) variation was evaluated. In those cases with this finding we manually measured the extension of the scleral protuberance and the choroidal shape.
Results: There were 166 eyes of 106 patients analyzed and 13% (22 eyes of 16 patients) demonstrated a focal scleral bulge. The scleral bulge was not visible ophthalmoscopically in any case. By SS-OCT, the scleral bulge had a mean basal diameter of 3225 microns (range 1954-4908 microns) and mean distance temporal to the foveola of 2261 microns (range 1148-4173 microns). Compared to normal submacular scleral thickness, the temporal scleral bulge was a mean of 107 microns thicker (range 31-171 microns). The mean overlying choroidal thickness was 177 microns (range 79-326 microns) compared with mean subfoveal thickness in the involved eye of 250 microns (range 99-431 microns), mean thickness at temporal edge of the bulge of 312 microns (range 195-529 microns). The overlying retinal pigment epithelium and inner retinal contour were normal in all cases.
Conclusions: On SS-OCT, 13% of healthy eyes showed temporal scleral bulge with related choroidal thinning. The clinical significance of this novel sign is under evaluation.