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Background: Contact lens discomfort is a symptom-based clinical diagnosis that affects 13% to 75% of contact lens wearers. The Tear Film and Ocular Surface Society defines contact lens discomfort as "a condition characterized by episodic or persistent adverse ocular sensations related to lens wear either with or without visual disturbance, resulting from reduced compatibility between the lens and ocular environment, which can lead to decreased wearing time and discontinuation from lens wear." Signs of the condition include conjunctival hyperemia, corneal and conjunctival staining, altered blinking patterns, lid wiper epitheliopathy, and meibomian gland dysfunction. Eye care specialists often treat contact lens discomfort with lubricating drops, including saline, although there is no clear evidence showing this treatment is effective and safe., Objectives: To evaluate the efficacy and safety of lubricating drops for ocular discomfort associated with contact lens wear in adults., Search Methods: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register), MEDLINE, Embase.com, two other databases, and two trials registries to May 2024, without date or language restrictions., Selection Criteria: We included parallel-group randomized controlled trials (RCTs) that evaluated lubricating drops, including saline, versus no treatment, or that evaluated lubricating drops versus saline, in adult contact lens wearers. We included studies regardless of publication status, language, or year of publication., Data Collection and Analysis: We applied standard Cochrane methodology. The critical outcome was contact lens discomfort. Important outcomes were corneal fluorescein staining and conjunctival redness. Adverse outcomes were incident microbial keratitis, inflammatory corneal infiltrates, and participant discontinuation. We assessed risk of bias for outcomes reported in the summary of findings table using the Cochrane risk of bias tool RoB 2, and we rated the certainty of the evidence using GRADE., Main Results: We included seven RCTs conducted in the USA, Canada, Italy, and France. They randomized a total of 463 participants to lubricating drops, saline, or no treatment. Four trials evaluated lubricating drops and saline versus no treatment, but one of them provided no usable outcome data. Three trials evaluated lubricating drops versus saline. Study characteristics All trial participants were adults, and the mean age ranged from 25.7 years to 36.7 years. The proportion of women varied from 15% to 82%. The trials lasted between one and four weeks. Of the five trials that reported contact lens discomfort, we judged three at high risk of bias, and considered the other two had some risk of bias concerns. Lubricating drops (including saline) versus no treatment Lubricating drops compared with no treatment may reduce contact lens discomfort, measured on a 37-point scale (lower is better), but the evidence is very uncertain (mean difference [MD] -5.9 points, 95% confidence interval [CI] -3.74 to -8.05; 2 RCTs; 119 participants). One trial found no difference between lubricating drops and no treatment in "end-of-day" comfort. The trial that compared saline with no treatment provided no results for the control group. Two studies measured corneal fluorescein staining on a scale of 0 to 20 (lower is better). We found low-certainty evidence of little to no difference between lubricating drops and no treatment in changes in the extent (MD -0.15 points, 95% CI -0.86 to 0.56; 2 RCTs; 119 participants), depth (MD -0.01 points, 95% CI -0.44 to 0.42; 2 RCTs; 119 participants), or type (MD 0.04 points, 95% CI -0.38 to 0.46; 2 RCTs; 119 participants) of corneal fluorescein staining scores. Regarding conjunctival redness, measured on a scale of 0 to 4 (lower is better), there was low-certainty evidence of little to no difference between lubricating drops and no treatment in nasal region scores (MD 0.10, 95% CI -0.29 to 0.49; 1 RCT; 73 participants) and temporal region scores (MD 0.00, 95% CI -0.39 to 0.39; 1 RCT; 73 participants). No studies reported microbial keratitis or inflammatory corneal infiltrates, and no trials reported vision-threatening adverse events up to four weeks of treatment. All trials reported the proportion of participants who discontinued participation. In two trials, no participants left any treatment group. Our meta-analysis of another two studies suggests little difference in the number of people who dropped out of the lubricating treatment group versus the no treatment group (risk ratio [RR] 1.42, 95% CI 0.19 to 10.94; 138 participants; low-certainty evidence). Lubricating drops versus saline Lubricating drops may have little to no effect compared with saline on contact lens discomfort measured on a visual analog scale of 0 to 100 (lower is better), but the evidence is very uncertain (MD 9.5 points, 95% CI -4.65 to 23.65; 1 RCT; 39 participants). No studies reported corneal fluorescein staining or conjunctival redness. No studies reported microbial keratitis or inflammatory corneal infiltrates, and no trials reported vision-threatening adverse events up to four weeks of treatment. Our meta-analysis of three studies suggests little difference in the number of people who dropped out of the lubricating treatment group versus the saline group (RR 1.56, 95% CI 0.47 to 5.12; 269 participants; low-certainty evidence)., Authors' Conclusions: Very low-certainty evidence suggests that lubricating drops may improve contact lens discomfort compared with no treatment, but may have little or no effect on contact lens discomfort compared with saline. Low-certainty evidence also suggests that lubricating drops may have no unwanted effects that would lead to discontinuation over one to four weeks. Current evidence suggests that prescribing lubricating drops (including saline) to people with contact lens discomfort is a viable option. However, most studies did not assess patient-reported contact lens (dis)comfort using a validated instrument. Therefore, further well-designed trials are needed to generate high-certainty evidence on patient-reported outcomes as well as on longer-term safety outcomes., (Copyright © 2024 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)

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.