Objective To investigate the clinical characteristics of prepapillary and preretinal vascular loops. Methods The clinical manifestation, results of the fundus fluorescein angiography, and the prognosis of 20 cases(24 eyes) with prepapillary and preretinal vascual loops were analyzed retrospectively. Results 66.7% of prepapillary and preretinal vascular loops were involved in one eye, and 95.8% of vascular loops were located within one optic disc diameter. There were different configuration types of the vascular loops. Among 20 cases(24 eyes) of the vascular loops, 70.8%(17 eyes) were arterial, 12.5%(3 eyes) were venous, and 16.7%(4 eyes) were both arterial and venous. 62.5% of eyes with prepapillary and preretinal vascular loops were associated with other congenital and developmental anomalies of retinal vascular vessels. Conclusion Most PRVL are arterial and superior to the optic disc. The serious distortion of the vascular loops may result in disturbance of blood flow in artery and retinal hemorrhage, which cause visual loss. (Chin J Ocul Fundus Dis, 1999, 15: 9-11)
Objective To investigate the changes of ocular hemodynamics in patients with retinal vein occlussion(RVO)． Methods The hemodynamic parameters(PSV,EDV,PI,Vmax)of central retinal artery(CRA)and central retinal vein(CRV)were measured in the involved eyes(n=48) with RVO and the contralateral clinically healthy eyes(n=39) and in the control eyes(n=40) by color Doppler imaging (CDI)(ATLHDI3000). Results Peak systolic velocity (PSV) and end diastolic velocity (EDV) were significantly lower in the CRA of involved eyes and clinically healthy eyes of patients with RVO compared with control eyes,and pulsatility index(PI)was significantly higher in the CRA of involved eyes of patients with RVO compared with control eyes．PSV were significantly lower in the CRA of involved eyes of patients with RVO compared with their clinically healthy eyes．Pulsatility index(PI)was significantly higher in the CRA of involved eyes of patients with RVO compared with their clinically healthy eyes．Maximun vein velocity (Vmax) was significantly lower in the CRV of involved eyes and clinically healthy eyes of patients with RVO compared with control eyes． Conclusion The changes of hemodynamics in CRA,CRV of involved eyes of patients with RVO may invade their clinically healthy eyes．CDI may be helpful to early diagnosis for RVO． (Chin J Ocul Fundus Dis,1998,14:111-113)
ObjectiveTo measure and analyze the oxygen saturation and retinal blood vessel diameter in the eyes of patients with convalescence Vogt-Koyanagi-Harada (VKH) syndrome. MethodsIn this cross-sectional study, 28 eyes of 14 patients with convalescence VKH syndrome (VKH group) and 20 eyes of 10 healthy subjects (control group) were enrolled. The oxygen saturation and retinal blood vessel diameter were detected by spectrophotometric oximetry unit. Retinal images were collected using filters with wavelengths of 570 nm and 600 nm in the darkroom by the same technologist and then the fused image was obtained. The oxygen saturation of retinal vessels was marked in different colors. The measurement was repeated 2-3 times for each patient, then take an average. A top-quality image in each eye was selected to detect the oxygen saturation and diameter of retinal vessel which located in 1.5-3.0 disc diameter from the optic disc. Image analysis and data acquisition were completed by another technologist. ResultsRetinal venous oxygen saturation was (54.34±8.05)% in the VKH group and (60.07±7.91)% in the control group. The former was lower than the latter, the difference was significant (t=2.443, P=0.017). The mean diameter of retinal arteries was (102.8±18.1) μm in the VKH group and (112.9±19.8) μm in the control group. The former was smaller than the latter, the difference was significant (t=2.406, P=0.018). There was no significant difference of the mean diameter of retinal veins, oxygen saturation of retinal arteries and the arterial-venous difference between two groups (t=-0.330, 0.804, -0.631; P=0.743, 0.403, 0.536). ConclusionsRetinal venous oxygen saturation and the mean diameter of retinal arteries are significantly decreased in patients with VKH syndrome. There is no significant difference of diameter of retinal veins, oxygen saturation of retinal arteries and the arterial-venous difference between VKH syndrome patients and healthy subjects.
OBJECTIVE :To investigate ocular vessel flow velocity in normal eyes by color Doppler imaging(CDI). METHODS: Ninety people (180 normal eyes)had flow velocity measured by CDI in three vessels,ophthalmic artery (OA),central retinal artery(CRA) and posterior ciliary artery (PCA),and the relations between velocity and affecting factors were analysed. RESULT: The diastolic and systolic velocity of OA,CRA and PCA were (31.7plusmn;10.9)cm/s, (7.2plusmn;2.6)cm/,s, (10.2plusmn;3.4)cm/s, (2.8plusmn;1.2)cm/s and (11.3plusmn;3.6)cm/s, (3.2plusmn;1.4)cm/s respectively. The velocity of OA had possitive correl-ativity with RBC,HCT and negative correlativity with age,while it revealed no relationship with sex, laterality of right or left eye,and normal IOP. CDI of ocular vessels in normal eyes is a triangle with three peaks and double sunkens in its frenquency spectum, revealed highly resistant,and both the pulsatility and resistive indexes were relatively high. The width of each frequency band basically was the same,and there was no obvious frequency window. CONCLUSION: The ocular application of CDI might lay the foundation of a comparatively comprehensive knowledge of the ocular hemodynamics. （Chin J Ocul Fundus Dis,1997,13: 99-101）
Objective To study the proximal diameter changes of retinal blood vessel following branch retinal vein occlusion (BRVO). Methods Color fundus photographs and fundus fluorescein angiography (FFA) photographs of 48 patients with typical unilateral BRVO were analyzed using IMAGEnet software. The diameter of retinal artery (RAD) and vein (RVD) close to optic disc (within one DD from the optic disc) in four quadrants including the affected quadrant were measured with linear measuring tools.Results The proximal diameter of RAD and RVD in corresponding normal quadrants of the BRVO eye had no significant change comparing with the contralateral eye. The proximal diameter of RAD, but not RVD of the affected quadrant such as superotemporal （t=-2.342, P=0.026）or inferotemporal （t=-3.069, P=0.010）quadrant, increased remarkably. Conclusions In corresponding affected quadrant with BRVO, only RAD close to optic disc increases markedly, RVD has no significant change.
Objective To investigate the effect of hypoxia on the exp ression and function of integrin receptor αvβ3 of bovine retinal vascular endotheliocytes. Methods Bovine retinal vascular endotheliocy tes in the culture dishes coated by vitronectin was put into the normal and hypoxemic condition, respectively. Enzyme linked immunosorbent assay and cell adhesion analysis were used to detect the expression and function of integrin receptor αvβ3 in bovine retinal vascular endotheliocytes, respectively. Results Under the condition of hypoxia, the expression of αvβ3 increased gradually, and reached the peak at the 48th hour. The expression of αvβ3 at the 60th and 72nd hour in hypoxia group was higher than that in the normal group. Bovine retinal vascular endotheliocytes absorbed more Vn of extra-cellular matrixes (ECM) after cultured under hypoxemic condition for 24 hours.Conclusion Hypoxia may up-regulate the expression of αvβ3, which promote the adsorbability of endotheliocytes.(Chin J Ocul Fundus Dis，2004，20：360-363)
ObjectiveTo explore the effect of estrogen on the permeability of retinal blood vessel by ovariectomy.MethodsTwenty-two healthy rats were divided into experimental and control group randomly. Estrogen level of rats decreased due to ovariectomy in the experimental group while stabilized by sham-ovariectomy in the control group. The results were confirmed by vaginal epithelium smearing. Retinal vein occlusion was established by photodynamic method, and leakage of Evan's blue in retina was determined by spectrophotometer.ResultsMature value of vaginal epithelium decreased significantly in ovariectomy rats（t=21.008，P=0.000） while not significantly in sham-ovariectomy ones （t=0.319，P=0.756）; the mean leakage of Evans blue was (25.503 0±4.378 47) ng/mg in experimental group, and (17.830 0±4.265 69) ng/mg in the control group, and the difference between the two groups is significant（t=3.969 36，P=0.001）.ConclusionOvariectomy is an useful method to study the effect of estrogen on ocular diseases, and when estrogen level decreases, the permeability of retinal blood vessel increases.(Chin J Ocul Fundus Dis, 2005,21:174-176)