Brief Article
Copyright ©2011 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Ophthalmol. Dec 30, 2011; 1(1): 4-10
Published online Dec 30, 2011. doi: 10.5318/wjo.v1.i1.4
Changes in peripapillary retinal nerve fiber layer thickness in patients with primary open-angle glaucoma after deep sclerectomy
Asaad A Ghanem, Salah M Mady, Hatem El-Said El-wady
Asaad A Ghanem, Hatem El-Said El-wady, Mansoura Ophthalmic Center, Faculty of Medicine, Mansoura University, 35516 Mansoura, Egypt
Salah M Mady, Department of Ophthalmology, Benha University, 2465 Benha, Egypt
Author contributions: Ghanem AA, Mady SM and El-wady HE contributed equally to this work, designed and performed research; Ghanem AA contributed new reagents/analytic tools, analyzed data and wrote the paper.
Correspondence to: Asaad Ahmed Ghanem, MD, Ophthalmology Center, Faculty of Medicine, Mansoura University, 35516 Mansoura, Egypt.
Telephone: +2-040-2973667 Fax: +2-050-2256104
Received: January 19, 2011
Revised: December 17, 2011
Accepted: December 22, 2011
Published online: December 30, 2011

AIM: To assess changes in peripapillary retinal nerve fiber layer (RNFL) thickness and visual field (VF) in patients with glaucoma after reduction of intraocular pressure (IOP).

METHODS: Thirty-five consecutive patients with bilateral high tension glaucoma were included in the study. Thirty-five eyes underwent monocular deep sclerectomy (surgery group) and the medically treated fellow eyes served as controls (control group). Quantitative analyses of the peripapillary RNFL thickness by optical coherence tomography (OCT) and global VF indices by automated perimetry were performed before surgery and six months after surgery in both eyes. The changes in RNFL thickness overall and by quadrant were evaluated and studied with respect to age, best-corrected visual acuity (BCVA), preoperative global VF indices, postoperative IOP changes, and postoperative changes in global VF indices. Changes observed in RNFL thickness and VF indices were compared between eyes after surgery and fellow eyes.

RESULTS: Six months after surgery, the overall IOP decreased from a baseline mean of 24.5 ± 3.2 mmHg to 11.5 ± 2.7 mmHg (P < 0.001) at the time of OCT testing. A significant increase in the overall mean RNFL thickness was observed after surgery (P < 0.001). The preoperative VF mean deviation was significantly correlated with a postoperative increase in the RNFL thickness (P < 0.075). No correlation was found between RNFL thickness changes and age, BCVA, or changes in the global VF indices. There was no significant difference between eyes with an IOP reduction of more than 50% and those with a reduction in IOP less than 30% (P = 0.312).

CONCLUSION: A significant increase in the peripapillary RNFL thickness was associated with IOP reduction by glaucoma filtration surgery as measured by OCT.

Keywords: Peripapillary retinal nerve fiber layer thickness, Optical coherence tomography, Visual field indices, Glaucoma medication, Deep sclerectomy