Comparison of central corneal thickness by ultrasound pachymetry, optical coherence tomography and specular microscopy

Salil Babbar,James B Martel,Matthew R Martel

doi:10.15761/nfo.1000164

Abstract

Comparison of central corneal thickness by ultrasound pachymetry, optical coherence tomography and specular microscopy

Highlights

Glaucoma is defined as optic disc atrophy with characteristic thinning of the outer rim of the optic nerve head with increased intraocular pressure (IOP), usually greater than 21 mmHg
The mean central corneal thickness (CCT) measured by ultrasound pachymetry from the 8 subjects was 531.47 ± 42.2 μm
The first Bland-Altman plot shows that the measurements acquired via ultrasound pachymetry were greater than those obtained by optical coherence tomography (OCT) pachymetry for all mean CCT values, except for one patient (Figure 1)

Summary

Introduction

Glaucoma is defined as optic disc atrophy with characteristic thinning of the outer rim of the optic nerve head with increased intraocular pressure (IOP), usually greater than 21 mmHg. By the time patients with glaucoma begin to experience visual loss, extensive optic nerve damage has already occurred. Glaucoma is diagnosed primarily by observing optic nerve cupping and retinal nerve fiber loss, along with increased intraocular pressure. The importance of measuring the central corneal thickness (CCT) of both eyes in suspected glaucoma patients has been previously reported [1]. IOP readings obtained by non-contact applanation tonometry can be falsely decreased in individuals with thin corneas and falsely elevated in individuals with thick corneas [2]. It is important to accurately assess the CCT in order to obtain correct IOP values to aid in the diagnosis and management of glaucoma

Objectives

Methods

Results

Conclusion