Comparison of central corneal thickness with optical coherence reflectometer and ultrasound pachymeter in early postoperative LASIK period

  • Volkan Hürmeriç
  • Orkun Müftüoğlu
  • Üzeyir Erdem
  • M. Zeki Bayraktar

Received Date: 06.09.2005 Accepted Date: 30.11.2005 Gulhane Med J 2006;48(1):11-13

The aim of this study was to compare the efficacy of optical low coherence reflec-tometer and ultrasound pachymeter in the measurement of central corneal thickness in preoperative and early post-operative LASIK surgery period. Twenty one eyes of the 12 patients who admitted to the Gulhane Military Medical Academy Ophthalmology Department, Cornea and Refractive Surgery Service were enrolled in the study. Five consequtive optical low coherence reflectometer measurements of the patients were taken at the first preoperative and 7th postoperative days with optical low coherence reflectometer and ultrasound pachymeter, respectively. If a difference of more than 10 microns has been detected, 3 additional measure-ments have been taken. Mean of the low-est 5 measurements has been recorded. Preoperative central corneal thickness was 535.5±28.9 microns with optical low coherence reflectometer, 535.4±28.5 microns with ultrasound pachymeter. Postoperative central corneal thickness was 472.3±34.5 microns with optical low coherence reflectometer, 471.8±34.9 microns with ultrasound pachymeter. There was no statistically significant dif-ference between the preoperative and postoperative central corneal thicknesses (p=0.915 and p=0.818, respectively). Mean ablation debth was 62.3±27.8 microns. The correlation betwen the ablation debth and postoperative central corneal thickness were high both with optical low coherence reflectometer (p=0.897) and ultrasound pachymeter (p=0.820). Optical low coherence reflec-tometer gives comparable results with ultrasound pachymeter in the measure-ment of central corneal thickness, and especially postoperative central corneal thickness measurement is superior to ultrasound pachymeter because it is a non-contact method.

Keywords: Optical coherence reflecto-metry, central corneal thickness, ultra-sound pachymeter