Fourth Ventricular AVM with Transdural Drainage.

Arteriovenous malformations (AVMs) of the fourth ventricle are exceptionally rare subtypes of brainstem AVMs. This report illustrates the case of a young man who suffered intraventricular and subarachnoid hemorrhage. Angiography depicted a fourth ventricular AVM that was supplied by branches of the right posterior inferior cerebellar artery and drained via a posterior medullary midline vein into the marginal sinus and cervical radicular and nuchal veins.

[Restoration of blood circulation in reperfusion of ischemic tissues].

In experiment there were studied changes of the tissue blood circulation and microcirculation during postischemic reperfusion of skeletal muscles with various density of capillaries. It was established that reactive hyperemia, caused mainly by enhancement of extracapillary tissue blood flow. While persistence of durable arterial hypertension the capillaries quantity and potential volume of microcirculatory bed are reducing, negatively influencing the blood circulation restoration process during postischemic reperfusion.

["Reperfusion collapse" phenomenon during post-ischemic reperfusion in experiment].

Postischemic changes of central and regional hemodynamic while various reperfusion regimens have been studied on animal experimental model. We had revealed that despite vasodilatation, peripheral vascular resistance in the postischemic extremity rises, as a result of reperfusion by the lowered perfusion volume. Such phenomenon has been named as "reperfusion-collapse".