Peripheral Vascular Leakage Findings of Asymptomatic Eyes Based on Fluorescein Angiography

PURPOSE: To report peripheral vascular retinal leakage findings of asymptomatic eyes based on fluorescein angiography, and investigate the associated factors. METHODS: Data were collected retrospectively from 47 subjects (94 eyes) and the peripheral leakage results based on fluorescein angiography were analyzed. The relationship between peripheral leakage findings and other factors including-arm-retinal circulation time (ARCT) and venous filling time (VFT), refractive error, age, hypertension, and diabetes- was evaluated. RESULTS: Ten eyes had peripheral leakage (21.3%). The mean age was 34.7 +/- 7.86 years in the non-leakage group and 44.3 +/- 9.63 years in the leakage group; the difference between the groups was statistically significant (p = 0.001). The mean spherical equivalent was -2.85 +/- 2.71 diopter in the non-leakage group and -3.46 +/- 3.62 diopter in the leakage group; the difference between the groups were not significant (p = 0.471). The mean ARCT was 10.50 +/- 2.06 seconds in the non-leakage group and 11.76 +/- 2.47 seconds in the leakage group; the difference between the groups was statistically significant (p = 0.041). The mean VFT was 9.70 +/- 1.91 seconds in the non-leakage group and 10.75 +/- 1.40 seconds in the leakage group; the difference between the groups was statistically significant (p = 0.048). CONCLUSIONS: Peripheral leakage can be found in asymptomatic eyes. Age, VFT, and ARCT were correlated to peripheral leakage findings based on angiography. These leakage findings were thought to be related with histological properties and physiological changes in peripheral retina.

The Clinical Significance of Venous Filling Time through Panretinal Photocoagulation in Proliferative Diabetic Retinopathy

PURPOSE: To verify the clinical correlation between retinopathy progression and the change of venous filling time (VFT), measured before and after panretinal photocoagulation (PRP), in proliferative diabetic retinopathy (PDR) patients. METHODS: We conducted this study on 32 patients (32 eyes) who received PRP for PDR. These patients were subdivided into two groups in accordance with the clinical course of PRP: the stabilized group in which retinal neovascularization was regressed and the progressed group in which retinal neovascularization was continued and a complication, such as vitreous hemorrhage or tractional retinal detachment, was developed within 12 months of laser treatment. Arteriovenous passage time (AVP) and VFT were measured by video fluorescein angiogram (FAG) using scanning laser ophthalmoscope (SLO) before and after PRP. VFT values were assigned by measuring by the time duration from start of venous lamina flow to the fullness of fluorescence on the vascular arch. RESULTS: In the stabilized group, AVP was decreased by 0.20+/-0.89sec and VFT was decreased by 0.30+/-1.69 sec through PRP. In the progressed group, AVP was increased in 0.12+/-1.22 sec and VFT was increased by 0.99+/-1.60 sec through PRP. In both groups, the VFT changes were significant (P=0.04) but the AVP changes were not (P=0.34). CONCLUSIONS: VFT was significantly decreased in the stabilized group and significantly increased in the progressed group after PRP. Accordingly, we suggest that VFT changes after PRP can be utilized as a prognostic indicator for evaluating clinical course of diabetic retinopathy after performing PRP and for monitoring the clinical effect of PRP.

The Clinical Usefulness of the Venous Filling Time in Proliferative Diabetic Retinopathy

PURPOSE: To evaluate the clinical usefulness of venous filling time (VFT) in proliferative diabetic retinopathy (PDR) and the relation of VFT with PDR complications. METHODS: Retinal circulation time (RCT) such as ART (arm to retinal circulation time), AVP (arteriovenous passage time), and VFT (venous filling time) were obtained by video fluorescein angiogram using SLO (Scanning Laser Ophthalmoscope), after which PRP (panretinal photocoagulation) was performed. We performed two studies on 39 patients, (39 eyes), who had PDR. In the first study, according to the development of complication, patients were classified into 2 groups, stabilized and complicated groups. In the second study, according to the score of the risk factor by DRS (Diabetic Retinopathy Study), patients were classified into 4 groups, A (1 score), B (2 score), C (3 score), and D (4 score) groups. RCTs, especially VFT were analyzed with each group. RESULTS: In the Mann-Whitney test, the Z-values of ART, AVP and VFT were -1.92, -0.49, and -2.59, respectively. There was a significant difference only in VFT(P<0.05). According to the risk factor scores, VFTs were 7.48 +/- 1.36, 7.84 +/- 0.91, 9.15 +/- 1.10, and 10.94 +/- 0.44 sec in A, B, C, and D groups, respectively. In each group, there were significant differences, except between A and B. CONCLUSIONS: VFT was delayed in the complicated group. With increasing risk factor score, VFT was more delayed. We suggest that VFT is a predictable indicator of the progression and development of complication in PDR.

The Comparision of Venous Filling Time Before and After Panretinal Photocoagulation in Proliferative Diabetic Retinopathy

PURPOSE: Diabetic retinopathy (DR) has influence on peripheral retina, and progression of DR is thought to make prolongation of peripheral retinal circulation. However, there has been no study on circulation of peripheral retina. This study is to make a comparision of peripheral retinal microcirculation between control, non-proliferative diabetic retin-opathy (NPDR), and pre-and post-panretinal photocoagulation (PRP) of proliferative diabetic retinopathy (PDR). METHODS: The authors performed the study on 19 control eyes and 68 DR eyes (NPDR 31, PDR 37) and PDR group was subdivided into before and after PRP. The authors measured arm to retinal circulation time (ART), arteriovenous passage time (AVP), venous filling time (VFT) by scanning laser ophthalmoscope in upper temporal retinal vessel in order to evaluate peripheral retinal microcirculation. RESULTS: VFT was 9.4+/-0.3 sec in pre-PRP of PDR, 7.5+/-0.6 sec (p<0.05) in post-PRP of PDR and 6.4+/-2.2 sec in control, 8.17+/-1.90 sec (p<0.05) in NPDR. However, there is no significant difference in ART, AVP. CONCLUSIONS: Patients with NPDR showed prolongation of VFT compared to normal indivisuals. There was shortening of VFT in post-PRP of PDR similar to NPDR. Peripheral retinal circulation time after PRP can be utilized as an indicator of PRP effect.

A Study on Microcirculation Time Including Retinal Periphery in Diabetic Retinopathy using the Fluorescein Angiography

On video fluorescein angiogram, it is known that arm-to-retinal circulation(ART)influences retinal macrocirculation and arterio-venous passage time(AVP)influences microcirculation.In diabetic retinopathy(DR), midperiphery involved earlier than posterior pole.However, there has been no study on the circulation of the entire retinal circulation including the peripheral retina. The authors conducted a prospective study by performing fluorescein angiography on 19 controls and 19 DR patients in order to measure the ART, AVP and venous filling time(VFT). The VFT correspond to the circulation of the peripheral retina. In the DR group, the retina circulation time was compared with the existence of proliferative diabetic retinopathy(PDR), distribution of nonperfusion area and beading vessels. There was no significant difference between diabetic group and the control group in the ART.AVP was 1.8+/-0.7sec in the control group and 2.5+/0.7sec(p=0.04)in the DR group and venous filling time was 6.4+/-2.4sec and 8.9+/-1.5sec(p=0.006)respectively. Patients with PDR showed prolongation only in VFT compared to patients with non-proliferative diabetic retinopathy(NPDR). In addition, patients presenting with nonperfusion areas and beading of vessels showed longer prolongation of VFT than of AVP. In conclusion, the VFT is delayed in DR compared to control group and in PDR compared to NPDR. The VFT can be utilized as an indicator of DR to measure the retinal circulation including the peripheral retina.