Abstract

Background: Gonioscopy is a traditional method of measurement of anterior chamber of eye and Optical Coherence Tomography (OCT) is newer method. Aims &
Objective: To compare the anterior chamber angle on gonioscopy & optical coherence tomography as well as evaluating the nerve fiber layer thickness & ganglion cell layer thickness in glaucoma patients. Material and Methods: Fifty patients who had bilateral glaucoma under treatment were selected randomly for this study. They all had controlled IOP i.e. less than 21 mm of Hg by Schiotz Tonometry. Complete anterior segment evaluation done including lids, lashes, conjunctiva, sclera, cornea, anterior chamber, iris, pupil, lens and eye movements, Posterior segment evaluation included cup disc ratio, disc pallor, neuro retinal rim, haemorrhages on disc margin; Gonioscopy with Volk four mirror goniolens was performed and diagnosis of glaucoma confirmed. The closed angles were defined as non-visibility of posterior trabecular meshwork on gonioscopy; On OPTOVUE RTVue optical coherence tomography machine patient was examined for retinal nerve fiber layer and ganglion cell complex. Descriptive statistics was used and values were shown as mean and percentages.
Results: Angle closed in > / = 1 quadrants by was observed in 47.5% by gonioscopy and 70% by OCT. In all quadrants (superior, inferior, lateral and medial) closed angle was more in OCT as compared to gonioscopy. Average retinal fiber thickness in the case of primary open angle glaucoma was 89.86µm while in the case of primary closed angle glaucoma it was 77.12µm. Average ganglionic cell thickness in the case of primary open angle glaucoma was 94.16 and in the case of primary angle closure glaucoma it was 87.08. Average central corneal thickness in open angle glaucoma was 533.96 μm and closed angle glaucoma it was 535.25 μm. Conclusion: Anterior segment OCT is a rapid noncontact method of imaging angle structures. Anterior segment OCT tended to detect more closed ACAs than gonioscopy, particularly in the superior and inferior quadrants.