Scleral Lenses For Visual Rehabilitation And Improvement Of Subjective Symptoms In Salzmann Nodular Degeneration

Salzmann nodular degeneration (SND) is a corneal disease characterized by whitish, grey or bluish nodules on the peripheral or central cornea which can cause foreign body sensation and/or blurred vision. Usual care for symptomatic SND is surgical management. However, scleral lenses (SL) can also be fitted to enhance vision by neutralizing induced irregular astigmatism and alleviating symptoms. They may be used as an alternative to surgery or as co-management after surgery. In this study scleral lenses were fitted for visual rehabilitation and relief of subjective symptoms as an alternative to or as co-management with surgical intervention in cases of SND.

A specialised contact lens practice in the Netherlands residing predominantly in hospitals and ophthalmology practices. Patients with SND were referred to the practice by the ophthalmology department.

A retrospective chart review was performed on all patients with SND and SL in the practice. A diagnostic trial set was used to fit the SL in each case with the focus on achieving full bridging over the Salzmann nodules. Charts were anonymously reviewed on best corrected visual acuity (BCVA) with glasses and with scleral lenses, SL characteristics such as base curve, diameter and design and SL wearing time.

A total of 61 SL were successfully fitted in 32 patients (26 female, 6 male). Mean (±SD) best-corrected visual acuity (BCVA) improved from 0.20 ± 0.26 logMAR with spectacles to 0.06 ± 0.21 logMAR with Sl. Mini-scleral lenses were the predominant design (85%). Mean (±SD) lens diameter was 16.2 ± 0.57 mm and 19.25 ± 0.96 mm for mini- and large-diameter scleral lenses, respectively. The patients were able to use their SL every day for a mean (±SD) of 13,52 ± 4,13 hours per day.

Scleral lenses, when correctly fitted, can be succesful in the management of SND symptoms and also in conjunction with surgical intervention. Visual acuity significantly improved compared to spectacles and patients demonstrated a high tolerance for the lenses, as evidenced by their consistent daily wear and prolonged hours of use.These findings support the efficacy and feasibility of SL in managing complex ocular conditions. Further research is needed to assess the place of the SL in the treatment plan for SND.