New Analysis Of Retinal Capillary Blood Flow Velocity By Fluorescein Angiography With Scanning Laser Ophthalmoscope

Abstract

Abstract: : Purpose: To evaluate the feasibility of new analysis method (Tracing method) for measurement of perifoveal capillary blood flow velocity in patients with clinically significant macular edema (CSME). Methods: The blood flow velocities of perifoveal capillaries were measured on 6 eyes in healthy subjects and 6 eyes in patients with CSME by fluorescein angiography (FA) using a scanning laser ophthalmoscope (SLO) and tracing method analysis. A randomized crossover design was applied. Results: The number of recognized capillaries by the tracing method in healthy subjects and in patients with CSME was significantly higher than that by the conventional method (p=0.0234 and p=0.0185). The number of recognized fluorescent dots by the tracing method in healthy subjects and in patients with CSME was significantly higher than that by the conventional method (p=0.0003 and p=0.0230). By using tracing method to outline the target capillary, accurate detection of the movement of fluorescent dot and analysis of blood flow velocity become possible in healthy subjects and in patients with CSME. The blood flow velocity varied in the same perifoveal capillary in either healthy individuals or patients with CSME and the mean blood flow velocity also varied according to capillary location in the macula. Conclusions: Our results show that the new analysis software is very useful to analyze the capillary blood velocity in healthy subjects and in patients with CSME and there are several variations of florescent dot movement according to perifoveal capillaries and capillary location.

Keywords: diabetic retinopathy • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • macula/fovea