On Heidelberg retinal tomography (HRT), which parameter best correlates with ganglion cell loss in glaucoma diagnosis?

• A Cup-to-disc area ratio
• B Mean retinal nerve fibre layer thickness
• C Cup volume
• D Rim volume ✓

Explanation

On HRT, rim volume (the three-dimensional measure of neuroretinal rim tissue) is the single parameter that best correlates with actual ganglion cell count and is most sensitive for detecting early glaucomatous loss. Rim volume is used in the Moorfields regression analysis incorporated into HRT software. Cup-to-disc area ratio and cup volume are indirect markers. Mean RNFL thickness is better assessed by OCT than HRT.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.