Abstract
Purpose :
This study investigates glaucoma's impact on lacrimal gland capacity using the i-Onion device.
Methods :
The i-Onion device introduces an innovative approach for assessing tear gland capacity. By emitting controlled bursts of highly concentrated CO2 (99.9%) onto the ocular surface, it stimulates the lacrimal glands' maximum secretory capacity. Study participants included 14 individuals with varying glaucoma severity and 40 controls. Participant information included age, gender, race, ethnicity, smoking, and contact lens use. Glaucoma severity, medication count, and disease duration were recorded. Tear capacity was tested using baseline unanesthetized Schirmer's measurements, followed by a 3-second i-Onion gas stimulation and repeat Schirmer’s measurements. The main outcome was the change in Schirmer (ΔSchirmer) post versus pre-stimulation. Secondary analyses explored correlations of demographic data, co-morbidities, and medications with maximum secretory capacity.
Results :
The mean age was 44±21 years, 31% self-identified as female, 79% as White, and 21% as Hispanic. Cases were significantly older than controls (68±20 vs 36±14 years[WCM1] ) and spent less time on electronic devices (2.6±1.2 vs 4.1±1.2 hours, p<0.001); other demographics were matched between the groups. Baseline and post-stimulation Schirmer scores were lower in cases versus controls (pre: 11.46±8.27 vs 19.02±10.90 mm, p<0.001; post: 19.38±11.06 vs 26.95±8.30 mm, p<0.001). However, ΔSchirmer was similar between the two groups (7.93±8.81 and 8.43±4.05 mm, p=0.77). These findings held even when adjusting for potential confounders, including age and device use. Within cases, baseline Schirmer, post-stimulation Schirmer, and ΔSchirmer were not significantly related to glaucoma severity (r=-0.06 to 0.34[WCM2] ), number of drops (r=-0.23 to -0.08, p>0.05), and duration of glaucoma (r=-0.24 to 0.01, p>0.05). Baseline Schirmer score was the only factor found to correlate with ΔSchirmer (r= -0.54, p<0.001).
Conclusions :
This study provides insights into lacrimal functional capacity in individuals with glaucoma using the i-Onion device. Glaucoma and topical glaucoma treatments do not seem to impact secretory tear capacity, measured as ΔSchirmer to a CO2 stimulus. Future research with larger numbers of participants and other ocular conditions may improve understanding of factors related to lacrimal gland function.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.