Developmental Venous Anomalies

Abstract

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 Management of Symptomatic Cerebral Developmental Venous Anomalies: A Clinical Experience of 43 Cases

“…The angiographic appearance of these anomalies is that a series of small deep veins converge towards a larger collector. One or more of these veins follow a transhemispheric course before draining into a normal deep or superficial vein [2,6]. …”

“…DVAs with one or more CMs are typically located in the region of the DVA’s caput medusae [4–6,12,13]. Based on MRI findings, Wurm et al [14] reported 15 of 58 patients (25.9%) with cerebral, cerebellar, or brain stem CMs also had associated DVAs.…”

“…DVAs were once thought to be rare lesions, however, with the advance of imaging techniques, especially the widespread use of magnetic resonance imaging (MRI), the detection rate for DVAs has increased dramatically [8,9]. DAVs have a benign natural course and good prognosis [4,6,10,11]. However, there is still controversy with respect to treatment strategies for symptomatic DVAs.…”

Image Findings in Brain Developmental Venous Anomalies

“…The reported high incidence of intracranial hemorrhage associated with DVAs in previous studies is currently attributed to the coexistence of a CM 7). Any DVA that presents with symptoms and signs that can be directly attributed to the DVA merits vigorous investigation using high-field MRI and TFCA, to exclude the possibility of a coexisting CM or of an arteriovenous malformation.…”

“…In most cases with DVA, angiographic studies illustrate the underdevelopment of the normal venous drainage pattern adjacent to a DVA 7). It is hypothesized that this results from a focal arrest of venous development and retention of primitive medullary veins that drain into a single, large draining vein.…”