Cerebellar developmental venous anomalies with associated vascular pathology

Cerebellar developmental venous anomaly with associated cavernoma causing a hemorrhage - a rare occurrence

Developmental venous anomalies (DVAs) are variations in the transmedullary veins required for drainage of the brain. Normally, when occurring in isolation, DVAs are not clinically significant and are therefore usually a benign diagnosis. Thus, they are most often an incidental finding unless associated with an adjacent pathology. However, intracranial haemorrhage induced by a DVA alone can rarely occur and has been scarcely reported. In this case report we discuss a 58-year-old woman who presented with signs and symptoms of a cerebellar syndrome. Following a non-contrast CT, a CT angiogram and MRI contrast scan of the brain, she was found to have a cerebellar DVA and an intracranial haemorrhage. Subsequent imaging 3 months later with CT and MRI redemonstrated additional evidence of a cavernoma. The patient was managed conservatively.

Developmental Venous Anomalies (DVA): What Are They Really?

Purpose: The aim of this paper is to analyse the pathophysiology of 3 DVA cases from our institution, review the literature and propose a classification of these lesions. Materials & Methods: The pathophysiology of DVAs were analysed with CT perfusion (CTP), 4 dimensional dynamic computed tomography angiography (4D CTA) and catheter digital subtraction angiography. Results: Symptomatic DVAs may be caused by associated lesions and compression of neural structures by the DVAs. The imbalance between the inflow and outflow of these lesions, including venous ischaemia, has also been postulated as a cause. Our analysis showed that increased cerebral blood flow (CBF) and cerebral blood volume (CBV) and decreased mean transit time (MTT) and time to peak (TTP) were found in DVAs with micro arteriovenous shunting. DVAs without shunting had raised MTT and TTP instead. Conclusion: We postulate that the arteriovenous shunting resulted in arterial steal and chronic hypoxia which could be a pathophysiological mechanism for symptomatic DVAs. CTP and 4D CTA are effective non invasive tools to study DVAs. A classification is proposed.

DEVELOPMENTAL VENOUS ANOMALIES

DEVELOPMENTAL VENOUS ANOMALIES (DVAs), formerly known as venous angiomas, have become the most frequently diagnosed intracranial vascular malformation. DVAs are currently considered congenital cerebrovascular anomalies with mature venous walls that lack arterial or capillary elements. They are composed of radially arranged medullary veins, which converge in an enlarged transcortical or subependymal collector vein, and have characteristic appearances (caput medusae) on magnetic resonance imaging and angiography. DVAs were once thought to be rare lesions with substantial potential for intracerebral hemorrhage and considerable morbidity. The prevalence of incidental and asymptomatic DVAs has been more apparent since the advent of magnetic resonance imaging; recent cohort studies have challenged the once-held view of isolated DVAs as the cause of major neurological complications. The previously reported high incidence of intracerebral hemorrhage associated with DVAs is currently attributed to coexistent, angiographically occult cavernous malformations. Some patients may still have noteworthy neurological morbidity or die as a result of acute infarction or hemorrhage directly attributed to DVA thrombosis. DVAs can coexist with cavernous malformations and arteriovenous malformations. Such combination or transitional forms of malformations might suggest common pathways in pathogenesis. Recent data support a key role for DVAs in the pathogenesis of mixed vascular malformations.

The Presentation and Clinical Course of Intracranial Developmental Venous Anomalies in Adults

Background and Purpose— Reported risks of hemorrhage from intracranial developmental venous anomalies (DVAs) vary, so we investigated this in a systematic review and population-based study.

Methods— We systematically reviewed the literature (Ovid Medline and Embase to November 7, 2007) and selected studies of ≥20 participants with ≥1 DVA(s) that described their clinical presentation and/or their clinical course over a specified follow-up period. We also identified every adult first diagnosed with a DVA in Scotland from 1999 to 2003 and followed them in a prospective, population-based study.

Results— Of 2068 articles detected by the literature search, 15 met our inclusion criteria and described clinical presentation, 8 of which also described the clinical course of DVAs. In the 15 studies of 714 people first presenting with a DVA, 61% were incidental findings, the mode of presentation was unclear in 23%, 6% presented with nonhemorrhagic focal neurological deficit, 6% had caused symptomatic hemorrhage, 4% were associated with epileptic seizure, and <1% were associated with infarction. In studies of the clinical course of 422 people with a DVA, the hemorrhage rate after first presentation ranged from 0% to 1.28% per year. In the population-based study of 93 adults with DVAs, 98% were incidental, 1% presented with symptomatic hemorrhage, and 1% presented with an infarct, but there were no symptomatic hemorrhages or infarcts in 492 person-years of follow-up (0% per person-year; 95% CI, 0% to 0.7%).

Conclusions— Intracranial DVAs have a benign presentation and clinical course.

Repeated intracerebral hemorrhage from developmental venous anomaly alone

Developmental venous anomalies (DVAs) are hemodynamically low flow, low resistance vascular malformations without clinical significance. Although most DVAs are asymptomatic and are found incidentally, sometimes they can be symptomatic with intracerebral hemorrhage, many of which are usually caused by associated cavernous malformations (CMs) rather than the DVAs themselves. Only a few cases have been reported in the literature where an intracerebral hemorrhage has been caused by a DVA alone. This report describes a case of an intracerebral hemorrhage due to DVA alone with review of the literature.