Abstract
Purpose::
The pathogenesis of normal-tension glaucoma (NTG) might be related to dysfunction in vascular autoregulation. To evaluate retinal hemodynamics by fluorescein angiography and to correlate the arteriovenous passage time (AVP) with ocular perfusion pressure in patients with NTG and age-matched controls.
Methods::
Thirty-five patients with untreated NTG (age 53 ±11 years) and thirty-five age-matched healthy controls (age 53 ±11 years) were included in this prospective study. Retinal hemodynamics were assessed by video fluorescein angiography using a scanning laser ophthalmoscope (Rodenstock, Germany). Dye dilution curves of temporal superior and inferior arteries and veins were performed by digital image analysis. The AVP was measured and correlated with mean arterial blood pressure and ocular perfusion pressure.
Results::
The AVP was significantly prolonged in patients with NTG compared to controls (1.8 ±0.6s versus 1.4 ±0.5s, p=0.002). Patients with NTG and healthy subjects showed no differences in intraocular pressure, mean arterial blood pressure or ocular perfusion pressure. The AVP was significantly correlated with mean arterial blood pressure (r=-0.54, p<0.001) and ocular perfusion pressure (r = -0.51, p=0.002) in patients with NTG, but not in controls.
Conclusions::
Patients with NTG exhibited significantly prolonged AVP compared to controls. In addition, patients with NTG showed a significant correlation of AVP with ocular perfusion pressure, while healthy controls demonstrated no correlation. The correlation of retinal hemodynamics with ocular perfusion pressure in patients with NTG only might reflect the disturbed vascular autoregulation in NTG.
Keywords: optic nerve • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • blood supply