Region-Specific Changes in Postlens Fluid Reservoir Depth Beneath Small-Diameter Scleral Lenses Over 2 Hours

Scleral lenses settle on the eye with time, and the depth of the postlens fluid reservoir decreases. We measured changes in central, superior, inferior, temporal, and nasal clearance beneath a small-diameter scleral lens after 2 hr of lens wear in healthy eyes.Thirty-one participants (age, mean±SD, 29±7 years) with no history of eye disease or scleral lens wear were fitted with a 15-mm scleral lens in 1 eye. Scheimpflug images were acquired by a camera system within 5 min of lens placement and again after 2 hr of continuous lens wear. The central cornea was located in both horizontal and vertical meridians, and lens clearance was measured at that point. Lens clearance was also measured 2 mm superior, inferior, nasal, and temporal to the center of the cornea.After 2 hr of lens wear, central clearance was reduced 46% (mean [SD], from 227 [77] to 122 [61] μm; P<0.001). Superior clearance was reduced 48% (from 168 [62] to 87 [61] μm); inferior clearance, 54% (from 241 [82] to 111 [55] μm); temporal clearance, 45% (from 224 [79] to 124 [74] μm); and nasal clearance, 52% (from 166 [73] to 80 [49] μm) (P<0.001 for all). Statistically significant decreases in clearance were noted at all points assessed after 2 hr of lens wear.Fluid reservoir depth beneath small-diameter scleral lenses decreased nearly 50% after 2 hr of lens wear in normal eyes.