Abstract
Purpose :
Ocular pain can have multiple contributors, including nociceptive, neuropathic, and nociplastic mechanisms. While autonomic function can modulate pain perception, there is a knowledge gap regarding how autonomic system status impacts ocular pain development. Since intraocular pressure (IOP) is one metric regulated by autonomic mechanisms, in this study we examined whether pre-surgery IOP measurements predicted the development of chronic pain after surgery.
Methods :
This study prospectively examined individuals prior to and after refractive surgery. Questionnaires regarding ocular symptoms were completed at baseline (pre-surgery) and 3 and 6 months after surgery. IOP was measured prior to surgery. Patients were asked to rate their worst eye pain over a 1-week recall using the numerical rating scale (NRS 0-10). Correlational and linear regression analyses were conducted with the primary outcome measure being an examination of whether baseline IOP (lower value of the two eyes used for analyses) predicted ocular pain at 3 and 6 months.
Results :
211 individuals were enrolled in the study and completed at least 3 months of follow-up, 186 completed 6 months of follow-up. The mean age of the population was 34 years (range 19 to 57); 60.7% self-identified as female, 80.6% as White, and 30.8% as Hispanic. The majority (87%) of individuals underwent LASIK. Lower IOP at pre-surgery baseline was correlated with higher ocular pain intensity at 3 and 6 months following refractive surgery, respectively (rho=-0.13, p=0.05; rho=-0.15, p=0.04). This association between lower IOP and increased pain was not impacted when demographics were considered in multivariable forward stepwise linear regression analyses.
Conclusions :
Lower IOP prior to refractive surgery had a weak correlation with the presence of ocular pain three and six months after refractive surgery, suggesting that autonomic mechanisms may contribute to pain development in some individuals.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.