Posters

Diurnal variation of anterior segment parameters in keratoconus patients and healthy controls

Poster Details

First Author: A.Çiçek TURKEY

Co Author(s):                        

Abstract Details

Purpose:

To investigate the diurnal variations in anterior segment parameters measured by Pentacam Scheimpflug camera  in keratoconus patients and healthy controls.

Setting:

Ophthalmology Department, Kayseri Education and Research Hospital, Kayseri, Turkey

Methods:

A total of 28 eyes from 14 patients with keratoconus and 14 eyes from 7 age- and sex-matched healthy individuals were included in this study. Each participant underwent a comprehensive ophthalmic assessment including best-corrected visual acuity, slit-lamp biomicroscopy, stereoscopic fundus examination, and intraocular pressureAnterior segment parameters were measured by Pentacam Scheimpflug camera. The measurement sessions occurred at morning (08:00), midday(12:00) and nightfall (16:00). Three consecutive measurements were performed in each measurement session to avoid high repeatability limit of Pentacam.

Results:

Anterior segment parameters did not show diurnal variation in control group (p>0.05). Both the central corneal thickness and corneal thickness at the thinnest location showed significant diurnal variation in keratoconus group (both p < 0.01). The mean amplitude of central corneal thickness change was 4.24±0.98 µm. The  peak in central corneal thickness was found to occur at morning. The minimum in central corneal thickness was found at nightfall. The other anterior segment parameters including maximal keratometry, astismatism,anterior elevation and posterior elevation didn’t show diurnal variation in keratoconus group.

Conclusions:

This is the first study investigating diurnal variation in anterior segment parameters measured by Pentacam Scheimpflug camera  in keratoconus patients and healthy controls. This study provides the evidence of diurnal variation occuring in central corneal thickness  and corneal thickness at the thinnest location measurements. Significant diurnal variation have not observed in control group. It is a sensible advice to perform anterior segment measurements at the same period of day during follow-up visits of keratoconus patients.

Financial Disclosure:

None