Comparative study of measurements of central corneal thickness (CCT) by ultra-sonic pachymetry (USP) VS non-contact pachymetry (NCP)

Abstract

This study aims to compare and measure the reliability, repeatability of USP and NCP (NIDEK NT530P) clinically.It was a hospital-based comparative study conducted in the outpatient department of Ophthalmology, CCT measurements were taken by NCP (NIDEK NT530P) and USP.This study done on 50 subjects, age group between 18-25 Years and it’s approved by IRB committee, subjects with emmetropia and low myopia only were included. Participants were subjected to comprehensive ophthalmic examination, Corneal thickness measurement taken with NCP(NIDEK NT530P) and USP. To eliminate the effect of diurnal variations on thickness all measurements were taken between 2 PM -6 PM.CCT measurements was first taken by NCP (Nidek NT530P) five readings were taken followed by USP. Eyes was anesthetized, and the probe placed perpendicularly on the cornea and the readings were observed in the display. The test was repeated five times and the mean values was calculated. The results were well inside the normal range and there are no significant measurements obtained by these devices.