Date of Award

January 2019

Document Type


Degree Name

Medical Doctor (MD)



First Advisor

Ji Liu

Second Advisor

Jimmy Z. Zhou


We sought to assess whether selective laser trabeculoplasty (SLT) and different types of anti-VEGF intravitreal injections had any effect on corneal sensation in human patients compared to controls. In a cross-sectional observational IRB-approved clinical study, we tested corneal sensation using a Cochet-Bonnet esthesiometer in 5 standard locations (temporal, superior, nasal, inferior, and central areas of the cornea). For patients receiving SLT (will be referred as the SLT study), corneal sensation was measured immediately prior to the operation and at the next clinic follow-up, in both the study and contralateral eye. For the anti-VEGF arm of the study (will be referred as the anti-VEGF study), sensation was measured at clinic follow-up after the last injection for the study eyes, while fellow eyes that had never received any intravitreal injections were used as controls. Comparisons of experimental groups to the control group was carried out using a Kruskal-Wallis one-way analysis of variance with Dunnett’s correction for multiple comparisons. Potentially confounding variables were controlled for using a stepwise multiple regression. P values were considered statistically significant when p < 0.05.

Forty-five eyes were included in the SLT study. Sensation in the central cornea was not significantly different from that in the peripheral cornea, both before and after laser in the treatment eye (p > 0.05). Stepwise multiple regression yielded no statistically significant predictors of change in corneal sensation in any sector, after SLT. Seventy-six eyes were included in the anti-VEGF study. There was a significant reduction in corneal sensitivity across all corneal locations in the aflibercept group when compared to the control group (p < 0.05 in the temporal, superior, nasal, inferior, and central locations, respectively). The bevacizumab group and the bevacizumab and aflibercept group did not differ significantly from the control group at any corneal location. The association of the aflibercept group with decreased corneal sensation across all corneal locations remained statistically significant after controlling for other variables with a stepwise multiple regression.


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