Comparative evaluation of the thickness of macula, ganglion cell layer, and retinal nerve fiber layer in emmetropes, myopes and myopes with lattice degeneration by using Cirrus high-definition optical coherence topography

Abstract

Purpose: To know the quantitative thickness changes occurring in the macula, retinal nerve fiber layer (RNFL), and ganglion cell layer (GCL) of the retina in myopic eyes (ME) and in ME with lattice degeneration (ME-LD) in comparison to emmetropic eyes, with the help of Cirrus HD Optical coherence topography (OCT) 5000 (Carl Zeiss Meditec Inc.). Methods: Hospital-based, nonrandomized prospective study involving 90 eyes, divided into three groups – Group A comprising 30 eyes with − 3–−6D of myopia, Group B comprising 30 eyes with − 3–−6D of myopia with LD and Group C with 30 emmetropic eyes. The central macular thickness (CMT), RNFL, and GCL analysis was done with Cirrus HD OCT 5000 (Carl Zeiss Meditec). Results: The CMT was significantly higher in Group A and B than Group C. There was no significant difference in CMT between Group A and B. Any of the group did not reveal significant difference in parafoveal thickness in any quadrant. Average RNFL, average GCL + inner plexiform layer (IPL), minimum GCL + IPL was significantly thicker in Group C than Group A and B. There was no significant difference between in CMT, average RNFL thickness, average GCL + IPL between Group A and B. Conclusion: There is a significant change in thickness of macula, RNFL, and GCL between emmetropes as compared to myopes and ME-LD but not between myopes and ME-LD. This underscores the need of incorporating a myopic normative database in the present normative built-up of Cirrus OCT. Patients of ME-LD, when being evaluated on different OCT-based parameters, can be considered the same as the myopic population.

Keywords

• cirrus high-definition optical coherence topography
• central macular thickness
• ganglion cell layer
• myopic lattice degeneration
• retinal nerve fiber layer