Comparison of the Prelaminar and Lamina Cribrosal Thickness in Patients With Primary open Angle Glaucoma and Normal Tension Glaucoma by Optic Coherence Tomography (Oct)
Mohammed Arish1, Seyed Mohammad Mirhosseini2, Elahe Rajaei3, Asma Arish4, Seyed Davood Mirhosseini5 and Alireza Dashipour61FRCS Edin., Alzahra eye hospital, Zahedan University of Medical Sciences, Zahedan, IR Iran.
2Alzahra eye hospital, Zahedan University of Medical Sciences, Zahedan, IR Iran.
3Alzahra eye hospital, Zahedan University of Medical Sciences, Zahedan, IR Iran.
4Insurance social hospital, Zahedan, IR Iran.
5Department of Pharmacy School, Shahid Beheshti University of Medical Science, Tehran, IR Iran.
6Department of Nutrition and Food Science, School of medicine, Zahedan University of Medical Sciences, Zahedan, IR Iran.
Corresponding Author E-mail: dr.mirhosseini.62@gmail.com
Abstract: According to differences between Primary Open Angle Gluacoma and Normal Tension Glaucoma (in pathogenesis, genetic, signs and symptoms) we tried to compare the Optical Coherence Tomography (OCT) appearance of the prelaminar and Lamina cribrosal thickness in these two disorders. So in this study we analyzed the anterior portion of the Optic Nerve Head in patients of primary open angle glaucoma (POAG) and normal tension glaucoma (NTG). 77 patients were analyzed between March 2013 till December 2014 according to the inclusion and exclusion criteria of this study; All patients aged between 30 to 65 years old. however, thirty-three (42.9%) patients (17 males and 16 female) of POAG and Forty-four (57.1%) patients of NTG group (22 males and 22 female). All of them underwent Enhanced Depth Image(EDI)-OCT (Carl ziess, sirus, 5000, German) on the first examination. Two observers measured the Optic Nerve Head Depth (ONHD), Anterior Surface of the Lamina Cribrosa depth (ASLCD) and Lamina Cribrosa Thickness (LCT) twice in each eye from the obtained EDI-OCT images manually and also measurement automatically was done by OCT relative program, finally Prelaminar Cribrosa Depth (PLCD) achieved by calculating the difference between ASLCD and ONHD mathematically. Independent sample T-test was used to compare means of PLCD, ONHD and LCT between the two groups (POAG & NTG). The results showed statistically significant variation between the two groups. Although mean of LCT was thicker in NTG group, PLCD and ONHD means were thinner. These findings support the notion that the LC is located more posteriorly in POAG group as compared with NTG group. And also LCT was significantly thicker in NTG group as compared with POAG group, so these two indices maybe considered as a point of differentiation between the POAG and NTG.
Keywords: Optical; Coherence; Tomography; According Back to TOC