Posters

Changes in biomechanically corrected IOP pre and post-LASIK

Poster Details

First Author: V.Kenia INDIA

Co Author(s):    P. Devani   R. Kenia   O. Pirdankar              

Abstract Details

Purpose:

Biomechanically corrected IOP (bIOP) measured using corvis ST is corrected for corneal thickness, age and corneal biomechanical response. Corneal biomechanics plays an important role in IOP measurement. Understanding the effect of corneal biomechanical changes on IOP is essential. Aiming to evaluate changes in IOP measurement due to corneal biomechanics pre and post LASIK (early phase).

Setting:

Kenia Eye Hospital, Mumbai, India.

Methods:

This was a prospective study where subjects who have undergone LASIK surgery between August 2017-February 2018 were included. Subjects aged between 21-35 years who fulfilled the criteria for LASIK were included. Subjects with history of systemic disease, ocular disease, or ocular surgery were excluded. Subjects with intra-operative and post-operative complication were excluded. Pre and post LASIK, pachymetry and IOP were recorded. IOP values pre- and post-LASIK (1 day) were measured using Corvis ST (biomechanically corrected (bIOP) and non-corrected (C-NCT)) and Nidek non-contact tonometer (NCT). Pre and post-LASIK IOPs for each instrument compared using paired T test (Two tailed, α<0.05).

Results:

Sixty eyes of 31 patients were enrolled and had mean±SD age 24.64±3.25 years. The mean±2SE pre-LASIK IOP using NCT, C-NCT and bIOP was 16.78±1.2, 17.45±1.3 and 17.16±1.0 mmHg respectively whereas post-LASIK IOP using NCT, C-NCT and bIOP was 13.58±1.4, 14.75±1.2 and 16.25±0.9 mmHg respectively. The mean difference in pre and post-LASIK IOP using NCT, C-NCT and bIOP was 3.2, 2.67 and 0.90 mmHg respectively. Statistically significant difference was noted in pre and post-LASIK IOP obtained using NCT, C-NCT, bIOP (p<0.001) however the difference in bIOP was not clinically significant.

Conclusions:

Statistical significant reduction in IOP was noted using NCT, C-NCT and bIOP however reduction in bIOP was clinically stable post LASIK. This suggest that bIOP is least affected by corneal biomechanical properties since it is corrected for corneal biomechanical properties and could be helpful in monitoring IOP in eyes with altered corneal biomechanics.

Financial Disclosure:

None