Abstract
Purpose: :
To use digital fluorescein angiography to document velocity in the retinal circulation in patients.
Methods: :
Patients' digital fluorescein angiograms were used to measure velocity by the equation velocity (µ/sec) = [distance (µm) /time (sec)]; (v)=(1000 µm)/(tfinal-tinitial); where distance=1000 µm. The measured distance was 1000 µm of the superior or inferior vein at the optic nerve. The measurement was made by the Topcon camera 50 EX, OIS Winstation-XP 3200, v.10.2.44. Fluorescein angiography (FA) was performed using Sodium Fluorescein 10% (Akorn, Buffalo Grove, IL) after an injection time of 5 secs. tinitial was defined as the time of cilioretinal artery appearance and tfinal was defined as the first appearance of a fully hyperfluorescent vein. Eligibility criteria for vision = 20/20 to 20/50. Digital FA of patients were examined:FA with minimal disease (MiniD: central serous choroidopathy, glaucoma suspect, retinal holes) and FA of severe vascular disease (SevD: Branch vein occlusion, central retinal vein occlusion, diabetic retinopathy and ocular ischemia).
Results: :
16 patients (pts) met the eligible criteria for vision and FA parameters: 8 MiniD, 8 SevD pts: MiniD pts age range=24-77 yrs, avg=48.8 yrs+15.9, SevD pts age range= 32-70 yrs, avg=53.8 yrs+14.3, (p=n.s). The severely diseased pts had lower velocity than the minimally diseased patients: MiniD pts: v(avg)= 104.32+20.0 µm/sec; SevD pts: v(avg)=71.96+18.4 µm/sec. (p<0.017, t-test).
Conclusions: :
The patients with severe vascular disease had a slower velocity than those with minimal retinal disease. This small study suggests that approximate velocity in the SevD vs MiniD patients can be assessed using available ophthalmic equipment. This measurement has the potential for monitoring disease progression and therapeutic intervention.
Keywords: imaging/image analysis: clinical • clinical (human) or epidemiologic studies: health care delivery/economics/manpower