Objective To observe the clinical characteristics of patients with macular branch retinal vein occlusion (MBRVO) and the changes of the area of foveal avascular zone (FAZ).Methods The data of 69 eyes of 69 patients with MBRVO, who had been diagnosed by ophthalmoscopy, slit-lamp examination and fluoresce in angiography, were retrospectively studied. The relationship of locations between artery and vein on the obstructive site, and the characteristics of fundus pictures, retinal vasculature changes and the complications were analyzed. In 69 patients with MBRVO, 36 had the course of disease for more than 3-6 months, of whom the area of FAZ was compared with that of 30 healthy people.Results In 69 patients, superior MBRVO occurred in 45 eyes (65.22%), and inferior MBRVO occurred in 24 eyes (34.78%). Most of the arteries were anterior to the veins at the obstructive site. Four clinical types of MBRVO were found, and the main complication was macular edema. There was a significant difference in area of FAZ between patients with MBRVO and healthy people (P＜0.05). Conclusion There are several clinical characteristics of MBRVO with different manifestations. The area of FAZ of patients with MBRVO is obviously lager than that of the healthy people. (Chin J Ocul Fundus Dis，2003，19：269-332)
ObjectiveTo observe the retinal microcirculation changes in chinchilla rabbit with branch retinal vein occlusion (BRVO), and to evaluate the feasibility of laser speckle imaging (LSI) technology as monitoring tool for retinal microcirculation. MethodsTen 4-month-old chinchilla rabbits were used for the experiment, selecting the right eye as the experimental eye. The main retinal vein, adjacent 0.5-1.0 mm to the optic of rabbit retina, was selected to the target vessel under surgical microscope. The software of LSI instrument was used to measure the diameter of target vein and blood flow of 0.2 mm2 area of target vein. The BRVO rabbit model was induced by photodynamic therapy, then measure the diameter and blood flow in the same region using the method as before and after 10 minutes modeled. ResultsThe retinal color pictures, infrared laser and the distribution of blood flow pseudo-color were synchronous displayed by LSI technology. Before and after modeling, the target vessel diameter were (0.104±0.009), (0.128±0.008) mm, and the 0.2 mm2 area blood flow of target vessel were (563.500±28.788), (256.000±53.319) PU. The diameter of target blood vessel after modeling was significantly thicker than before, with the significant difference (t=12.14,P=0.008). The blood flow in 0.2 mm2 area of target vessel was significantly lower than before, also with the significant difference (t=183.00,P=0.009). ConclusionsThe diameter of target vessel of the BRVO rabbit model is enlarged, and the target vessel area of 0.2 mm2 blood flow is reduced significantly. LSI system can monitor the retinal microcirculation real-time and quantitatively.
ObjectiveTo observe the contrast sensitivity (CS) of patients with branch retinal vein occlusion (BRVO) without involving the macular region. Methods92 BRVO patients (93 eyes) and 56 cases (112 eyes) without eye diseases (control group) were included in the study. According to different region, BRVO patients were divided into the nasal BRVO group (31 eyes) and temporal BRVO (62 eyes) group, and the average corrected visual acuity was 1.02±0.13 and 0.98±0.12 respectively. According to the type of ischemia, BRVO patients were divided into the nonischemic BRVO group (58 eyes) and ischemic BRVO group (35 eyes), the average corrected visual acuity was 1.01±0.14 and 0.99±0.12 respectively. The average corrected visual acuity of the control group was 1.03±0.11. There was no statistically significant difference of the average corrected visual acuity between nasal BRVO group, temporal BRVO group and control group (F=3.03, P=0.06), and between nonischemic BRVO group, ischemic BRVO group and control group (F=1.60,P=0.20). Contrast sensitivity (CS) was measured by OPTEC 6500 vision tester (Stereo Company, USA) under the standard lighting conditions and different spatial frequencies including low (1.5 and 3.0 c/d), medium (6.0 c/d) and high frequencies (12.0 and 18.0 c/d). ResultsThe CS under each spatial frequency of the nasal BRVO group was the same as the control group (t=4.25, 9.48, 3.08, 5.86, 0.94; P>0.05), but the CS under each spatial frequency of the temporal BRVO group was different from the control group (t=8.59, 19.11, 10.38, 17.28, 6.01; P<0.05). The CS under high spatial frequency of the temporal and nasal BRVO group was statistically different (t=11.42, 6.95; P<0.05). The CS under each spatial frequency of the ischemic BRVO group was different from the control group (t=8.88, 10.56, 11.64, 19.06, 6.67; P<0.05).The CS under 6, 12 and 18 c/d spatial frequency of the nonischemic BRVO group was statistically different with the control group (t=10.14, 11.54, 2.82; P<0.05). The CS under 12 and 18 c/d spatial frequency of the nonischemic BRVO group was statistically different with the ischemic BRVO (t=7.52, 3.84; P<0.05). ConclusionsThe CS of the temporal BRVO and ischemic BRVO decreased more significantly under each spatial frequency. CS is a better indicator to evaluate the visual function than the visual acuity in BRVO without involving the macular region.