Changes in Scleral Tonometry and Anterior Chamber Angle after Short‐term Scleral Lens Wear

SIGNIFICANCE: Scleral lens wear can alter aqueous fluid and anterior chamber angle dynamics, leading to changes in intraocular pressure (IOP). However, there is limited information supporting this relationship between scleral lens wear, anterior chamber angle (ACA), and IOP changes in an black African population. PURPOSE: The purpose of this study was to compare scleral IOP and ACA before, during, and after 4 hours of scleral lens wear in healthy neophyte scleral lens wearers from an black African population. METHODS: This was a prospective study involving 20 eyes of 20 subjects with a mean ± standard deviation age of 28.7 ± 4.3 years. The study was divided into a screening and experimental phase. Scleral lenses from a diagnostic trial set were fit on a randomly selected eye. Scleral IOP was measured using a Schiotz tonometer (Winters, Jungingen, Germany) (weight, 7.5 g) on the superior-temporal sclera, and ACA was assessed using anterior segment optical coherence tomography on the temporal angle before scleral lens wear; at 10 minutes, 2 hours, and 4 hours during wear; and 10 minutes after scleral lens removal. RESULTS: The mean ± standard deviation base curve of the scleral lens fit in the study eye was 43.4 ± 1.3 D with average tear reservoir thickness of 288.1 ± 122.0 μm at 4 hours. The mean scleral IOP before lens wear was 17.2 ± 3.5 mmHg, decreased to 16.4 ± 4.5 mmHg at 4 hours of scleral lens wear, and was 16.6 ± 3.5 mmHg 10 minutes after lens removal. The temporal ACA before scleral lens application was 43.0 ± 6.6° and varied during the 4 hours of scleral lens wear, ultimately increasing to 45.0 ± 5.4° at 10 minutes after scleral lens removal. The change in IOP and ACA was not statistically significant (F = 0.501, P = .74; and F = 2.399, P = .09, respectively). CONCLUSIONS: Results suggest that 4 hours of nonfenestrated scleral lens wear did not have a significant impact on IOP or ACA in most of our study population.