Abstract
Purpose: :
Previous fluorescein angiographic studies (e.g. Graefe’s Arch Clin Exp Ophthalmol 2005; 243:659–664) revealed significantly increased vascular leakage of the optic disc in primary open–angle glaucoma (POAG). To correlate capillary fluorescein leakage of the optic disc with retrobulbar hemodynamics in patients with POAG.
Methods: :
Forty–eight patients with POAG were included in a prospective study. Flow velocities (peak systolic velocity (PSV) and end–diastolic velocity (EDV)) and resistive indices of the ophthalmic artery (OA), central retinal artery (CRA) and nasal and temporal posterior ciliary arteries were measured by means of color Doppler imaging. In video fluorescein angiograms (Scanning Laser Ophthalmoscope, Rodenstock, Germany) fluorescein leakage of the optic disc was quantified 9–10 min after injection of the dye using digital image analysis. A leakage ratio (fluorescence of the optic disc versus retinal background) was determined and correlated to retrobulbar blood flow velocities.
Results: :
The fluorescein leakage ratio (1.34 ±0.35) of the optic disc is significantly correlated with the EDV of CRA (2.32 ±0.7cm/s, r = –0.30, p<0.05). No correlation was found for any other retrobulbar vessel or for intraocular pressure.
Conclusions: :
Fluorescein leakage may reflect endothelial dysfunction of the optic disc related to increased vascular permeability. Since decreased flow velocities of the CRA are related to increased capillary leakage, both phenomena might be due to a primary vascular dysfunction in POAG.
Keywords: optic disc • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • imaging/image analysis: clinical