Clinical Ophthalmology (Dec 2014)
Comparison study of OCT, HRT and VF findings among normal controls and patients with pseudoexfoliation, with or without increased IOP
Abstract
Fryni Riga, Ilias Georgalas, Panagiotis Tsikripis, Dimitrios Papaconstantinou Department of Ophthalmology, University of Athens, Athens, Greece Purpose: To compare and evaluate optic nerve head (ONH) and retinal nerve fiber layer (RNFL) measurements obtained with the optical coherence tomography (OCT) and the Heidelberg retina tomography (HRT) to visual field (VF) parameters in normal and in patients with pseudoexfoliation with or without increased intraocular pressure (IOP).Methods: A total of 96 subjects were included in our study aged between 65 years and 78 years. The normal group consisted of 28 subjects (14 men and 14 women). Out of the total number of patients, 68 patients who showed pseudoexfoliation (21 men and 47 women) were divided into two groups. Of these, the first group had pseudoexfoliation with increased IOP and the second group showed deposits of pseudoexfoliative material without an increase in IOP. The normal controls were randomly chosen and restricted to those without any glaucomatous optic disc damages, VF defects, and an IOP <15 mmHg. All subjects were prospectively included for repeated measurements of IOP, OCT, HRT, and VFs during the same visit by the same examiner and all measurements were repeated every 3 months.Results: Mean RNFL thickness measured by OCT was larger in the normal controls than in the other two groups (98.04 µm (first group) vs 75.42 µm and 97.02 µm (second group), P<0.05). Four-quadrant RNFL thickness measurements were significantly different between the normal and the group 1 (P<0.05) but not with the group 2 (P>0.05). Rim area had a mean difference of -0.44, whereas cup-to-disc ratio (C/D) showed a mean difference of 0.31, thus being significantly different between the normal and the two groups (all P<0.05). The median of the mean deviation parameter of VFs was -0.28 for the normal vs -0.32 and -0.18 for the other two groups, whereas pattern standard deviation median difference was 0.89 for the normal and 1.32 and 1.20 for the other two groups, respectively (P<0.05).Conclusion: Both OCT and HRT showed early ONH and RNFL changes in their parameters and did not correlate with the normal findings of the automated perimetry. Keywords: pseudoexfoliation syndrome, pseudoexfoliation glaucoma, optical coherence tomography (OCT), Heidelberg retina tomograph (HRT), retinal nerve fiber layer (RNFL), visual fields (VFs)