Corneal topography using Placido disc principle measures which property of the cornea DIRECTLY?

• A Anterior corneal curvature ✓
• B Corneal thickness
• C Posterior corneal elevation
• D Corneal biomechanical stiffness

Explanation

Placido-disc based corneal topographers directly measure anterior corneal curvature (power map) by analysing the reflection of concentric rings off the tear film surface; the distance and shape of ring reflections are used to compute local curvature. Corneal thickness requires optical coherence or Scheimpflug (Pentacam) imaging. Posterior corneal elevation is provided by Scheimpflug or slit-scanning systems. Corneal biomechanical properties are assessed by the Ocular Response Analyser or Corvis ST.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.