Abstract
Purpose :
It is known that chronic use of antiglaucoma topical treatment can both diminish corneal sensitivity, as well as increase the risk of ocular surface disease in glaucoma patients, leading to poorer compliance and decreased quality of life. While laser panretinal photocoagulation leading to neurotrophic corneal ulcerations has been attributed to findings of reduced corneal sensation, it is unclear whether laser therapy in glaucoma patients could have a similar effect. The purpose of this study was to examine the effects of selective laser trabeculoplasty (SLT) and laser iridotomy (LI) on corneal sensation.
Methods :
In a prospective IRB-approved clinical study, we tested corneal sensation using a Cochet-Bonnet esthesiometer in 5 standard locations (central, temporal, superior, nasal, and inferior areas of the cornea) in glaucoma patients (n=14) receiving either unilateral SLT (n=9) or LI (n=5). Sensation was measured immediately prior to the operation and at the next clinic follow-up, in both the laser and contralateral eye. Changes in sensation were averaged across all 5 locations for each eye. Two-tailed Student's t-test was used for statistical analysis.
Results :
Mean time to first follow-up after laser surgery was 17.89 ± 6.91 days (mean ± SE). None developed significant postoperative complications. Patients had mildly reduced central corneal sensation of 4.71 ± 0.38 cm and 4.75 ± 0.34 cm in both the laser and contralateral eye, respectively, prior to laser surgery. This reduced corneal sensitivity persisted (4.64 ± 0.34 cm across all eyes), even when excluding for patients with diabetes (n=5). Sensation in the central cornea was not significantly different from that in the peripheral cornea, both before and after laser (p>0.05). Changes in corneal sensation after laser were -0.17 ± 0.31 cm, 0.06 ± 0.21 cm, -0.22 ± 0.35 cm, 0.28 ± 0.39 cm, and 0.11 ±0.2 cm in the temporal, superior, nasal, inferior, and central areas, respectively. These changes were not statistically different from those observed in the contralateral eye (p>0.05). Neither SLT nor LI led to significant loss of central or peripheral corneal sensation (p>0.05).
Conclusions :
Pre-laser corneal sensation in non-diabetic glaucoma patients was equally reduced centrally and peripherally. Our findings suggest that SLT or LI are unlikely to cause significant alterations in corneal sensation. No area was more significantly impacted than another by laser.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.