Incidence of complications associated with long- term wear of scleral rigid gas-permeable contact lenses in keratoconus

Background. Scleral rigid gas-permeable contact lenses (SCL) are the preferred method for visual correction in keratoconus (KC). However, complications associated with long-term scleral lens wear remain understudied in the scientific literature. Evaluating the incidence and spectrum of these complications is essential for optimizing patient management and enhancing the safety of scleral lens use in clinical practice. Purpose: To assess the frequency and types of complications associated with long-term scleral lens wear in patients with keratoconus. Materials and methods. The study included 50 patients (100 eyes) with bilateral stage I–IV keratoconus (Amsler–Krumeich classification). The mean age was 29.2 ± 4.3 years. All patients underwent standard ophthalmic examination prior to the selection of optical correction. Slit-lamp biomicroscopy and anterior segment optical coherence tomography (AS-OCT) were used to monitor and identify potential complications during scleral lens wear. Follow-up duration was 12 months. Results. A total of 86% of patients (n = 43) successfully adapted to scleral lenses, with a mean adaptation period of 20.4 ± 5.8 days and an average daily wear time of 11.2 ± 2.4 hours. The primary reasons for discontinuation (14%, n = 7) were handling difficulties (42.9%) and lens damage (28.6%). Among patients who continued lens wear, handling challenges were reported in 25.6%, conjunctival hyperemia in 16.3%, and vision blurring in 9.3%. At the 12-month follow-up, the following complications were observed: mechanical (conjunctival hyperemia – 16.3%, corneal epithelial abrasions – 2.3%), toxic-allergic (2.3%), and infectious (2.3%). No statistically significant correlation was found between daily wear time and complication rate (p = 0.371). However, prolonged adaptation (>20 days) significantly increased the risk of discontinuation (p = 0.002). Conclusion. Long-term scleral lens wear in keratoconus is associated with complications, primarily of mechanical origin. These findings highlight the need for regular follow-up to ensure timely detection and management of complications.