Reproducibility of Perifoveal Fluorescent Dots Velocity Measurements on Fluorescein Angiography with a Scanning Laser Ophthalmoscope

To evaluate the reproducibility in measuring the velocities of perifoveal hyperfluorescent dots, we analyzed fluorescein angiographs of 24 eyes[24 patients]which had central serous retinopathy. Fluorescein angiography was performed with a scanning laser ophthalmoscope[SLO, Rodenstock, Mnchen, Germany]Distances between 5 moving hyperfluorescent dots in a perifoveal capillary were measured at each consecutive frame[interval 1/30 sec]. And then velocities of 5 fluorescent dots were measured with image analysis program by converting the distances to real retinal size using the Littmann's curve in 20 eyes. In the other 4 eyes, the velocities between 5 fluorescent dots of each 2 to 4 capillaries were measured. Perifoveal capillary mean blood flow velocity and standard deviation were 2.08 +/-0.36 mm/sec, and mean coefficient of variation of the velocities measured in a vessel of one patient was 12.58%. However, reliability of the velocities of 2 to 4 capillaries on the 4 eyes was relatively low. In conclusion, the measurement of velocities between perifoveal fluorescent dots with scanning laser ophthalmoscope may be a reproducible method for a perifoveal capillary. However, reliability of measuring velocities was not sufficient enough to use the velocity of one perifoveal capillary as macular blood flow.

The Macular Circulatory Change in Branch Retinal Vein Occlusion

We evaluated the macular circulatory change with fluores- cein angiography in 41patients (44eyes) who were diagnosed to have branch retinal vein occlusion and followed for 6 months or longer. Final visual acuity improved to 0.5 or better in more than half of cases in their last follow up. The initial corrected visual acuity and size of macular ischemic area were the potent prognostic factors. All cases that showed initial visual acuity of above 0.5 had smaller macular ischemic area and obtained final visual acuity of above 0.5. Visual prognosis of patients with ischemic area less than 1quadrant was much better than those with larger ischemic area. The state of perifoveal capillary network was also potent prognostic factor. Final visual prognosis was slightly better in patients with intact perifoveal capil-lary network than those with broken network. Systemic hypertension and venous occlusive site were not associated with visual prognosis. The relationship between visual improvement and state of perifoveal capillary network was not certain.

Macular Ischemia in Temporal Branch Retinal Vein Occlusion: Fluorescein angiographic classification and Visual prognosis

There have been various report about visual prognosis in branch retinal vein occlusion according to location and size of occluded vessel, status of perifoveal capillary ring, presence of retinal ischemia and hypertension. We therefore sought to determine prognostic indicators of BRVO by observing retrospectively the natural course of the BRVO with macular ischemia. To do that, we devide 63 eyes with BRVO into groups according to the macular perfusion status on high-quality fluorescein angiography. The patients without broken capillary ring exhibited better initial, final visual acuity and visual improvement. The patients with the extent of macular ischemia under 90degree exhibited better initial and final visual acuity but same visual improvement. There were no statistically significant difference in visual prognosis according to the status of perifoveal capillary ring, extent of macular ischemia and presence of hypertension.