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Changes in Optical Density of Postlens Fluid Reservoir During 2 Hours of Scleral Lens Wear
Muriel M Schornack1, Cherie B Nau
1Department of Ophthalmology, Mayo Clinic, Rochester, MN.
Objectives:
Debris accumulation in the postlens fluid reservoir during scleral lens wear is clinically observed. We evaluated a method to quantify increases in turbidity of the postlens fluid reservoir by assessing changes in optical density of the fluid over time and compared these changes during 2 hr of scleral lens wear using three different lens designs.
Methods:
Thirty-five patients (age, mean [SD], 29 [7] years) with no history of eye disease were enrolled in the study. Participants were fit with a 15.0-, 18.0-, and 18.2-mm scleral lens on one randomly selected eye during the enrollment examination. During each of three subsequent visits, one of three lenses selected during enrollment was placed on the eye. Scheimpflug images were acquired within 5 min of lens placement and at 20-min intervals for the ensuing 2 hr. Fluid reservoir optical density was assessed using Pentacam (Oculus Inc) analysis software.
Results:
Increases in fluid reservoir optical density were significant between each time interval with all lenses until 100 min. No significant increases in fluid reservoir optical density were noted with the 15.0- and 18.0-mm lenses between 100 and 120 min; fluid reservoir optical density increased with the 18.2-mm lens between 100 and 120 min. Optical density increased by 105% (15.0-mm lens) and 117% (18.0- and 18.2-mm lenses) at 2 hr.
Conclusions:
Optical density of the postlens fluid reservoir can be quantified during scleral lens wear. During 2 hr of wear, fluid reservoir optical density doubled with all lens designs evaluated.
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