Venous Angiomas (Venous Malformations) are the most common
type of intracranial vascular malformation with an estimated
prevalence of approximately 2.5% of the general population.
A Venous Angioma is characterized by an enlarged
collection of veins which, other than their size, are microscopically
normal. These enlarged veins receive drainage from adjacent
healthy Brain. The veins have a characteristic appearance of
a radial arrangement, all converging on an enlarged central venous
trunk. This trunk drains into healthy superficial or deep
venous systems. Venous Angiomas are not associated with
abnormal arteries and are generally regarded as anomalies
rather than pathological structures.
Most patients that are identified with Venous Angiomas are consequent
to an incidental neuroimaging study.
Most patients with a Venous Angioma are completely
asymptomatic and have no need for any
While it is generally accepted that Venous Angiomas have a very low
risk of bleeding, intracranial hemorrhage may be the presenting
symptom for a small percentage of patients. Patients may also
present with new onset seizure or focal neurological deficit.
Posterior Cranial Fossa (back & lowest "chamber" of the interior
of the Skull) lesions are more likely to result in some form of
Angiograms usually have a "hydra" or "caput medusae"
appearance consequent to the image of small radial veins converging
on a central draining venous trunk. CT or MRI Scans usually
demonstrate a curvilinear structure that resembles the spokes of a
Venous Angiomas are usually part of the normal venous drainage system
for normal Brain. Therefore, surgical removal can lead to a disastrous
venous infarction of the surrounding and adjacent brain resulting in
significant morbidity and mortality. Excision or ablation of venous
Angiomas is to be avoided except for very unusual circumstances.
Surgical intervention may occasionally be appropriate in a
patient with a Venous Angioma to remove a clot after a
hemorrhage; however, it is more likely that the bleeding
originated from a Cavernous Angioma since the two appear to be
In a case of a hemorrhage associated with a Venous Angioma,
it is imperative to investigate the patient for an adjacent Cavernous
Angioma. If a Cavernous Angioma is found, surgical removal of
the clot and the Cavernous Angioma is appropriate while leaving the
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This page last edited on 2/19