Understanding subepithelial corneal nerve plexus using a novel software in refractive surgery

Session Details

Session Title: Presented Poster Session: Keratorefractive Surgery Results II

Venue: Poster Village: Pod 2

First Author: : G.Mahadevan INDIA

Co Author(s): :    R. Shetty   P. Ahuja   P. Khamar                 

Abstract Details

Purpose:

To quantify corneal nerve morphological changes in vivo confocal microscopy(IVCM) images using a novel software in healthy and diseased corneas.

Setting:

Narayana Nethralaya Multispecialty Eye Hospital, Bangalore.

Methods:

Corneal sub-basal nerve plexus(SBNP) morphological features were studied in patients with evaporative dry eye(EDE), Keratoconus(KC) and Post-LASIK ectasia(PLE). IVCM images were analysed using Automated CCmetrics software, version 1.0 to determine SBNP features (corneal nerve fibre length–CNFL, fibre density–CNFD, fibre width–CNFW, total branch density–CTBD, nerve branch density–CNBD and fibre area–CNFA). SBNP features were measured in EDE (52 eyes), KC (33 eyes), PLE (12 eyes), post-LASIK eyes with no ectasia (14 eyes) and matched heathy controls (43 eyes). Statistical analysis was done using GraphPad Prism and P<0.05 was considered to be statistically significant.

Results:

We observed a significant(P<0.05) decrease in CNFL, CNFD, CNFW, CTBD, CNBD and CNFA in EDE patients compared to controls. CNFD and CNFL was observed to be significantly(P<0.05) lower in the KC eyes compared to both unaffected contralateral eyes and that of controls, with no significant changes in CNBD, CTBD, CNFA and CNFW. In PLE, CNFL and CNFD was observed to be significantly(P<0.05) lower in the eyes with higher degree of ectasia in the PLE eyes, however, no such differences were observed in SBNP features in the post-LASIK eyes without ectasia.

Conclusions:

IVCM analysis using Automated CCmetrics software offers a fast, unique and non-invasive method to study corneal nerve morphology in a variety of ocular surface conditions, and may be used as an imaging marker for screening of refractive surgery patients for subclinical inflammation and monitoring the response to treatment.

Financial Disclosure:

None