Scleral Lens Fenestrations and Fluid Reservoir Debris

The accumulation of debris within the fluid reservoir during scleral lens wear can adversely affect vision, resulting in the need for lens removal. This study aimed to quantify the effect of incorporating limbal scleral lens fenestrations upon fluid reservoir debris.

Twenty healthy adults (mean age 32 ± 11 years, 10 females/10 males) with normal corneas wore non-fenestrated and fenestrated (3 × 1 mm diameter limbal fenestrations separated by 120°) OneFitMed+ scleral lenses (No.7 Contact Lenses) in both eyes (on separate days) for 3 h. All other scleral lens parameters were held constant except for the addition of the fenestrations by the manufacturer. Customised image analysis (MATLAB) was used to quantify central fluid reservoir debris (an average and total intensity metric) from Scheimpflug images of the right eye.

Fluid reservoir debris increased over time (p < 0.001), more so for non-fenestrated lenses. After 3 h, the increase in fluid reservoir debris was greater for the non-fenestrated lens design (total metric increase: non-fenestrated 66 ± 21 vs fenestrated 14 ± 7 arbitrary units [p = 0.03], average metric increase: non-fenestrated 9 ± 2 vs fenestrated 5 ± 1 arbitrary units [p = 0.07]). There was no significant difference in the magnitude of debris for fenestrated lenses fitted with or without an air bubble (p = 0.80). There was no association between central corneal oedema and the fluid reservoir intensity metrics for either the fenestrated (R² ≤ 0.08, p ≥ 0.28) or non-fenestrated lenses (R² ≤ 0.001, p ≥ 0.90).

After 3 h, non-fenestrated lenses displayed a 2 (average metric) to 4.8 times (total metric) greater increase in central fluid reservoir debris than fenestrated lenses. This suggests a potential role for fenestrated lens designs in managing fluid reservoir debris; however, longer-term studies of participants with ocular disease are required.

This study was registered on the Australian New Zealand Clinical Trials Registry (Registration number 12622001164785p), date of registration 24/8/2022.