[Circulatory consequences of retinal vein occlusions. Advantages of dynamic angiography]

To compare angiographic features in patients with branch vein (BRVO) and central retinal vein occlusion (CRVO) and to discuss their possible significance.

Clinical and indocyanine green (ICG) videoangiographic data of 35 patients with CRVO and 5 patients with BRVO were reviewed. In order to more fully understand the significance of hemodynamic alterations, patients with a decrease in retinal flow velocity from other causes (optic neuritis, carotid-cavernous fistula, carotid artery stenosis) were compared to patients with vein occlusion.

Whatever the type of occlusion, the most frequent abnormality was the presence of pulsatile venular outflow, which at the acute phase was present in the majority of cases. The decrease in arterial velocity was visualized by the presence of diastolic reversed flow. There was no correlation between visual prognosis and hemodynamic alterations. Apart from vein occlusion, the pulsatile venular outflow was present in situations where increased venous pressure was present.

BRVO and CRVO have similar alterations of venous flow. Videoangiography can electively show pulsatile venular outflow and reverse diastolic arterial flow, and thus contributes additional information to conventional angiography. Pulsatile venular outflow is probably due to a combination of elevated venous pressure and decreased plasma velocity. Videoangiography provides new insight to the consequences of retinal vein occlusion and will possibly lead to a better understanding of the sequence of events that lead to visual loss.