Abstract
Purpose :
There is limited knowledge regarding the impact of corneal surface lubricants used during pars plana vitrectomy (PPV) on corneal edema. This prospective, observational clinical study tests the hypothesis that the use of Provisc® (Alcon, Switzerland) will be associated with a significantly smaller increase in corneal thickness after PPV as measured by pachymetry when compared to the group using Goniovisc® (Hub Pharmaceuticals, USA).
Methods :
We recruited patients over age 18 who had already consented to undergo PPV. Patients were excluded if significant corneal pathology, such as Fuch’s Dystrophy or corneal scar, was present. Choice of corneal lubricant was made by the surgeon performing the procedure based on his or her standard of care. Corneal thickness was measured pre- and post-operatively using pachymetry and anterior segment optical coherence tomography (AS-OCT). Other collected data included: patient age and sex, indication for surgery, lens status, history of prior scleral buckle or PPV, history of diabetes, type of corneal lubricant used, average intraocular pressure, type of retinal tamponade, need for corneal debridement, duration of surgery, use of contact lens, use of dextrose infusion, and clinical assessment of corneal edema. A bivariate analysis was completed to analyze the relationship between corneal lubricant and other factors.
Results :
47 patients were consented for the study and 41 patients completed study protocol. 18 patients were in the Goniovisc group and 23 were in the Viscoat group. Baseline patient characteristics and results can be seen in Table 1. Patients in the Viscoat group had a significantly smaller increase in corneal thickness as measured by pachymetry compared to the group using Goniovisc (29.9 um vs 58.1 um, p-value 0.02). When measured by AS-OCT, the Viscoat group had a smaller increase in corneal thickness compared to the Goniovisc group (40 um vs 60 um, p-value 0.09) but did not reach significance. No corneas required intraoperative debridement.
Conclusions :
Our results are consistent with our hypothesis that the use of Viscoat is associated with a significantly smaller increase in corneal thickness after PPV when measured by pachymetry. However, when measured by AS-OCT, the smaller increase in corneal thickness in the Viscoat group did not reach statistical significance. If confirmed in larger studies, these results could result in improved outcomes for PPV.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.