Aqueous Humor and Plasma Levels of Vascular Endothelial Growth Factor and Nitric Oxide in Patients with Pseudoexfoliation Syndrome and Pseudoexfoliation Glaucoma Yonca A. Akova, MD, Mehmet Borazan, MD; Aylin Karalezli, MD; Cem Kucukerdonmez, MD; Ahmet Akman, MD; Sevsen Kulaksizoglu, MD Baskent University, School of Medicine Department of Ophthalmology, Ankara, Turkey

Financial Interest  I have received research reimbursement from Alcon and Allergan which was not relevant to the subject matter of this poster  None of the authors have financial interest in the subject matter of this poster

Introduction  Pseudoexfoliation syndrome (PXS): Common Age-related May lead to pseudoexfoliative glaucoma (PXG) Specific pathogenetic mechanism and its progression to PXG remain, poorly understood  Pseudoexfoliation fibrils: Multifocal Produced by various intraocular cell types

Purpose To investigate the levels of vascular endothelial growth factor (VEGF) and nitric oxide (NO) in aqueous humor and plasma in eyes with pseudoexfoliation syndrome (PXS), pseudoexfoliative glaucoma (PXG), and normal controls

Patients and Methods  Prospective, randomized clinical study  37 patients with PXS  15 patients with PXG  32 control subjects  VEGF levels: Measured with enzyme-linked immunosorbent assay  NO levels: Measured with chemiluminescence method (nitrate/nitrite colorimetric assay kit)

Patients and Methods  Pseudoexfoliation syndrome: Presence of typical pseudoexfoliation material on the anterior lens capsule in one or both eyes A normal optic disk appearance and visual field testing (Humphrey 30-2 SITA standard test) IOP < 21 mm Hg  Pseudoexfoliative glaucoma: IOP > 21 mm Hg Typical glaucomatous cupping and visual field loss in one or both eyes Pseudoexfoliative material on the anterior lens capsule  Control group: Age-and sex-matched patients with cataracts Absence of any pseudoexfoliation material at the anterior segment of the eye

Patients and Methods  Aqueous humor samples: (0.1mL) Collected at the beginning of, phacoemulsification surgery through a clear corneal paracentesis Aspirated from the central pupillary area using a 27- gauge needle on a tuberculin syringe Cooled at – 70  C until analyses  Venous blood samples : (5 mL) Collected in the fasting state just before patients were prepared for cataract surgery Stored in chilled tubes containing EDTA (1mg/mL blood) and heparin (100 IU/mL blood) Centrifuged to obtain plasma Cooled – 70  C until analysis

Results Pseudoexfoliation Syndrome (n=37) Pseudoexfoliation Glaucoma (n= 15) Controls (n=32) P value Age (years) Range Mean±SD72.3 ± ± ± Sex Male, n(%)20 (54)8 (53)17 (53) Female, n(%)17 (46)7 (47)15 (47)0.82

Pseudoexfoliation Syndrome (n=37) Pseudoexfoliation Glaucoma (n= 15) Controls (n=32) Aqueous humor VEGF (µmol/mL) ± 55.47* ± 46.65* ± NO (ng/mL)34.96 ± $ ± # ± Plasma VEGF (µmol/mL)72.82 ± 23.82*83.70 ± 16.35*44.08 ± NO (ng/mL)18.89 ± ± ± 5.60 Results VEGF: vascular endothelial growth factor; NO: nitric oxide *: P <.001, PXS vs control, PXG vs control # : P =.001, PXG vs control $ : P <.05, PXS vs control

Discussion  Well documented iris vasculopathy, with manifestations of blood aqueous barrier defects, vessel dropout, microneovascularization, hypoperfusion, and anterior chamber hypoxia in PSX 1  Aqueous humor VEGF levels were found higher in neovascular glaucoma, POAG, angle-closure glaucoma and PXG 2,3  Controversial findings about aqueous NO levels in glaucoma in the literature 4-6  Kotikoski et al (only report on the aqueous concentration of NO in eyes with PXG) showed lower NO levels in 6 patients with PXG and 2 patients with PXS compared with controls 7 1. Helbig H, et al. Ger J Ophthalmol 1994;3: Tripathi RC,et al. Ophthalmology 1998;105: Hu DN, et al. J Glaucoma 2002;11: Chang CJ, et al. 2000;16: Galassi F, et al. J Ophthalmol 2004;88: Kosior-Jarecka E, et al. Klin Oczna 2004;106: Kotikoski H, et al. Acta Ophthalmol Scand 2002;80:

Conclusions  Aqueous humor VEGF and NO levels and plasma VEGF levels in patients with PXS and PXG were found higher than in controls  No significant difference was found in plasma NO concentrations compared with controls  The aqueous humor and plasma VEGF and NO levels were not significantly different in eyes with PXS compared with PXG  Improved understanding of the role of VEGF and NO in the pathogenesis of PXS and related glaucoma may change anti- glaucomatous treatment and anti-VEGF drugs may be an option for these patients

NAME: Yonca Aydın Akova, M.D. TITLE: Professor in Ophthalmology DATE AND PLACE OF BIRTH: October 21, 1960, Turkey 1983: Doctor of Medicine, Istanbul University, School of Medicine 1990: Istanbul University, School of Medicine, Department of Ophthalmology 2000:Professor of Ophthalmology, Baskent University, School of Medicine, Department of Ophthalmology, Ankara, Turkey 2002: Chairperson, Baskent University, School of Medicine, Department of Ophthalmology, Ankara, Turkey NAME: Mehmet Borazan, M.D. TITLE: Fellow in Ophthalmology DATE AND PLACE OF BIRTH: August 10, 1974, Turkey 1998: Doctor of Medicine, Inonu University, School of Medicine 2005 : Başkent University, School of Medicine, Department of Ophthalmology NAME: Aylin Karalezli, M.D. TITLE: Fellow in Ophthalmology DATE AND PLACE OF BIRTH: July 4, 1974, Turkey 1998: Doctor of Medicine, Ankara University, School of Medicine 2005 : Başkent University, School of Medicine, Department of Ophthalmology NAME: Cem Küçükerdönmez, M.D. TITLE: Fellow in Ophthalmology DATE AND PLACE OF BIRTH: October 9, 1975, Turkey 1999: Doctor of Medicine, Hacettepe University, School of Medicine 2003 : Başkent University, School of Medicine, Department of Ophthalmology NAME: Sevsen Kulasizoglu, M.D TITLE: Fellow in Biochemistry DATE AND PLACE OF BIRTH: April 10, 1974, Turkey 1998: Doctor of Medicine, Hacettepe University, School of Medicine 2003 : Başkent University, School of Medicine, Department of Bıochemistry NAME: Ahmet Akman, M.D. TITLE: Professor in Ophthalmology DATE AND PLACE OF BIRTH: March 20, 1968, Turkey 1991: Doctor of Medicine, Hacettepe University, School of Medicine 1995: Hacettepe University, School of Medicine, Department of Ophthalmology 2007:Professor of Ophthalmology, Baskent University, School of Medicine, Department of Ophthalmology, Ankara, Turkey