Follow up by colour Doppler imaging of 102 patients with retinal vein occlusion over 1 year

Abstract

Background/aim: Retinal vein occlusion (RVO) is one of the most frequent ocular vascular diseases and leads to severe vision impairment. Colour Doppler imaging (CDI) is the first method which allows distinct evaluation of arterial and venous velocities in RVO. CDI is valuable for diagnosis of RVO and shows the effects of isovolaemic haemodilution. Patients with RVO were monitored by CDI for 1 year in order to clarify venous and arterial involvement in the pathogenesis of this disease. Methods: Patients with RVO were monitored prospectively for 1 year with clinical examinations, fluorescein angiography, and CDI every 3 months. 102 adults referred for RVO for less than 2 months were enrolled. Unaffected eyes were used as control. The maximum systolic and diastolic flow velocities and the resistance index (RI) were measured in the central retinal artery (CRA) and the maximum and minimum blood flow velocities in the central retinal vein (CRV). Results: During the year of observation, branch retinal vein occlusion (BRVO), ischaemic central retinal vein occlusion (CRVO), and non-ischaemic CRVO had a distinct pattern of venous velocity changes. BRVO had a similar profile to that observed in controls. Venous velocities were continuously lower in central forms, with the lowest values in ischaemic occlusion. In contrast, a brief decrease in arterial diastolic velocity was observed in ischaemic CRVO at presentation, correlated with arteriovenous passage time on fluorescein angiography, but with rapid normalisation. Conclusions: CDI findings were correlated with the type of RVO at all times during follow up. CDI showed persistent impairment of central venous velocity in CRVO whereas there was a fast initial values recovery of the arterial velocity. These results using CDI show strong evidence of a primary venous mechanism in RVO.

Retinal Blood Flow Correlates to Aqueous Vascular Endothelial Growth Factor in Central Retinal Vein Occlusion

“…22 Arséne et al have also reported that the minimum blood velocity of CRV in the ischemic type of CRVO (1.83 cm/sec) was lower than that of the non-ischemic type (2.28 cm/sec). 23 Our study also indicated that the aqueous VEGF concentration for the ischemic type was significantly higher than that for the non-ischemic type. Noma et al found that the vitreous levels of VEGF were significantly higher in ischemic versus non-ischemic CRVO patients.…”

Color doppler imaging of orbital vessels: Personal experience and literature review

“…The central retinal artery velocity was similar in affected and unaffected eyes in all groups. 32 These results demonstrated the involvement of veins and not arteries in the process of central RVO. Differences in the recanalization of the CRV or in the development of collateral vessels might explain the divergent results between the studies.…”

“…A high RI in the CRV would be a predictor of decreased visual acuity. Arsene et al 32 observed that the V min in the CRV remained lower in ischemictype eyes than it did in eyes of control subjects and in patients with central RVO 1 year after hemodilution, whereas the V min in the CRV was similar in both affected and unaffected eyes in patients with the nonischemic and branch types of RVO. The central retinal artery velocity was similar in affected and unaffected eyes in all groups.…”

Colour Doppler Imaging of Ocular and Orbital Blood Vessels in Retinal Diseases

“…8,14,17 [27][28][29][30] and fellow eyes. [31][32][33][34] It has also been suggested that a characteristic decrease in the blood flow velocity in the central retinal vein was highly predictive of iris neovascularisation. 30 Most of the studies in eyes with CRVO that investigated arterial blood flow reported impaired blood flow parameters in the retrobulbar arteries, suggesting that altered arterial blood flow is involved in the pathogenesis of CRVO.…”

“…30 Most of the studies in eyes with CRVO that investigated arterial blood flow reported impaired blood flow parameters in the retrobulbar arteries, suggesting that altered arterial blood flow is involved in the pathogenesis of CRVO. [30][31][32][33][35][36][37][38] In branch retinal vein occlusion (BRVO), there have been reports of non-significant differences 34 …”