Abstract
Purpose: :
To analyze the correlation between optic nerve head morphometric characteristics and the lamina cribrosa shift estimated with Heidelberg Retinal Tomograph (HRT-III) in short-term intraocular pressure (IOP) induced rise.
Methods: :
260 persons (457 eyes) were enrolled in the study. They were subdivided into groups of primary open angle glaucoma (149 patients, 269 eyes, mean age 65.4 ± 2.27 years), ocular hypertension (26 patients, 52 eyes, mean age 59.1 ± 2.08 years) and healthy volunteers (98 persons, 162 eyes, mean age 56.8 ± 6.57 years). In vivo compression test was used to assess lamina cribrosa impact. The mean cup depth (MCD) of the optic disc was evaluated with HRT-III. After baseline examination suction cup was used to increase IOP for 10 mm Hg above initial level, and MCD was determined again. IOP was controlled with "Pascal" Dynamic Contour Tonometer before and during suction. IOP elevation resulted in MCD increase, and we suppose that MCD change may be considered to be an indirect measure of lamina cribrosa biomechanics in short-term IOP increase.
Results: :
A moderate negative correlation between optic disk area and lamina cribrosa shift was received in groups of glaucoma (R = -0.162, p = 0.014) and healthy volunteers (R = -0.161, p = 0.0175). There was no correlation between cup area and lamina cribrosa shift (R = 0.036, p = 0.15).
Conclusions: :
Our data show probable dependence between optic disc size and its biomechanics.
Keywords: optic disc • imaging/image analysis: non-clinical • laser