Corneal sub-basal nerve plexus density and post-PRK pain

Session Details

Session Title: Photoablation Outcomes II

Session Date/Time: Wednesday 09/09/2015 | 08:00-09:30

Paper Time: 08:30

Venue: Room 1

First Author: : S.Mohammadi IRAN

Co Author(s): :    M. Mohebbi   K. Asna-Ashari   A. Rafat-Nedjad   M. Kasiri   S. Heidari-Keshel        

Abstract Details

Purpose:

There is a high variability in the perceived pain by subjects who undergo PRK. In this study, we want to evaluate if sub-basal nerve plexus density would be predictive of the reported pain level.

Setting:

Refractive Surgery Ward of Farabi Eye Hospital, Tehran

Methods:

50 left eyes of 50 myopic PRK candidates who consecutively consented to scanning slit confocal microscopy (HRT3, Heidelberg Eye Explorer, version 1.7.0.0) assessments were included. ImageJ (1.48v) was used to measure the captured sub-basal nerve length. Pain was assessed by Visual Analogue Scale next day of surgery (score range: 0 to 10).

Results:

Mean age of the patients was 27.55 (19-40) years. Mean corrected spherical equivalent was -3.05 (-0.75-5.5) Diopters. The median reported pain level was 5. About 32.7% of subjects reported a pain score of 6 or higher. Mean nerve length was 19.54 (14.34-24.73) microns. The nerve length was not correlated with the reported pain. But pain was significantly correlated with the external eye inflammatory signs (P = 0.001). No other refractive, operative and subject-related factor was associated with pain level.

Conclusions:

Crude density of corneal nerves may not be a good predictor of post-PRK pain - while eyes are wearing bandage contact lenses; as the predominant pain mechanism seems to be of inflammatory nature (vs. nociceptive and neuropathic).

Financial Interest:

NONE