A recent study found that the optical density of the post-lens fluid increases over time with miniscleral lens wear and has a negative impact on low-contrast visual acuity (VA).

Researchers evaluated 23 eyes of 13 keratoconus patients who were fit with a miniscleral lens. The team analyzed the lens fit, optical density changes, high- and low-contrast VA, subjective comfort and vision and overall satisfaction with the lens.

They discovered that the mean best-corrected high- and low-contrast VAs significantly improved with scleral lens use (0.8±0.1 and 1.3±0.2 vs. 0.4±0.2 and 1.2±0.2, respectively). Patients reported high scores for comfort, vision and overall satisfaction with the lens. However, the investigators noted that optical density significantly increased over time, and although high-contrast VA remained stable, low-contrast VA significantly decreased after two hours of lens wear.

“The removal of the scleral lens for cleaning and reinserting may be a practical approach to avoid any negative impact on VA with consideration to settling and the increased optical density in the post-lens tear layer,” the study authors concluded in their paper.

Turhan SA, Yigit DD, Toker E. Impact of changes in the optical density of postlens fluid on the clinical performance of miniscleral lenses. Eye Cont Lens. November 29, 2019. [Epub ahead of print].