Posters

Corneal collagen cross-linking in keratoconus in thin corneas using iso-osmolar riboflavin 0.1% in HPMC

Poster Details

First Author: S.Chaudhary INDIA

Co Author(s):    J. Goyal   V. Veerwal                 

Abstract Details

Purpose:

To assess intra-operative changes in pachymetry in patients of keratoconus with thin corneas undergoing collagen cross-linking (CXL) using iso-osmolar riboflavin 0.1% dye in Hydroxy-propyl Methyl Cellulose(HPMC).

Setting:

The study was conducted in a Guru Nanak Eye Centre, Maulana Azad Medical College, New Delhi, India.

Methods:

Fifteen eyes of 15 patients with progressive keratoconus with thin corneas (pachymetry <440�Â�µm) were included in this study. After epithelial removal using 20% absolute alcohol, priming with iso-osmolar riboflavin 0.1% dye in HPMC was done for 30 minutes. Post priming pachymetry was repeated and if corneal thickness was >400 �Â�µm, UV-A radiation at 3mW/cm2 was applied for 6 cycles of 5 minutes each. At the end of each cycle, iso-osmolar riboflavin 0.1% in HPMC was instilled. Intraoperative corneal thickness changes were measured using ultrasound pachymetry. Post-operative demarcation line were measured using Anterior Segment OCT.

Results:

The mean age of patients was 17�.1years. Mean pre-operative corneal thickness was 393?(range 375-437�Â�µm) which reduced to 358.5�.55�Â�µm(p<0.05) post-epithelial removal. A significant increase in corneal thickness to 451.66�.86�Â�µm was seen post priming(p<0.005). Further increase in corneal thickness to 498.66�.54�Â�µm was noted post CXL application(p<0.005). There was a significant difference in corneal thickness intra-operatively before and after epithelial removal, after priming, and after UV-A radiation. Mean absolute change in intra-operative corneal thickness was 99.66�Â�µm(p<0.005). Postoperatively stromal demarcation line was noted at a mean depth of 264 �Â�± 22�Â�µm at 1month follow-up.

Conclusions:

A significant increase in intra-operative corneal thickness was seen when CXL was performed using iso-osmolar riboflavin 0.1% dye in HPMC. Post-operative demarcation line was noted to be at an adequate depth signifying the efficacy and safety of the procedure. This overall signifies that CXL can be safely applied in cases of keratoconus with thin corneas when iso-osmolar riboflavin in 0.1% HPMC is used instead of hypo-osmolar riboflavin in dextran.

Financial Disclosure:

NONE