Posters

A new technique for fitting of tricurve rigid gas-permeable contact lens in penetrating keratoplasty eyes using Scheimpflug imaging

Poster Details

First Author: P.Gogri INDIA

Co Author(s):    F. Bhombal                    

Abstract Details

Purpose:

Rigid gas permeable (RGP) contact lens fitting after penetrating keratoplasty (PK) is challenging due to significant irregular astigmatism. The aim of the study was to determine a guideline for selecting the initial base curve (BC) of the RGP contact lens fitting in post PK eyes.

Setting:

Tej Kohli Cornea Institute, L V Prasad Eye Institute, Hyderabad, India.

Methods:

The data of patients who had tricurve RGP contact lens fitting post PK were collected retrospectively. Following data were collected: best corrected visual acuity (BCVA) with glasses and contact lenses; contact lens parameters which included the BC and diameter; corneal topography parameters which included steep keratometry value (K), flat-K, mean-K; and anterior Best Fit Sphere (BFS) measured using Scheimpflug imaging.

Results:

The median age of the 40 subjects (46 eyes) who met the inclusion criteria was 37.5 years (IQR 26.7-45.5). The spherical equivalent was –3.00 diopter (D) (–8.31 to –1.56). The median steep-K, flat-K and mean-K in them were 6.76 mm (6.28-7.07), 7.78 mm (7.37-8.14) and 7.26 mm (6.93-7.46) respectively. The median anterior BFS value of the transplanted cornea was 6.96 mm (6.6-7.37). The median BC of final RGP lens was 7.0 mm (6.7-7.23) and the median diameter was 9.8 mm (9.4-10.4). Among all the Scheimpflug imaging parameters, the BFS correlated well with final BC of the RGP contact lens dispensed.

Conclusions:

The anterior corneal surface BFS value can be used as a reference in selecting the initial base curve of tricurve RGP contact lens to achieve the best fitting and reducing the chair time of patients after PK.

Financial Disclosure:

None