Brain Cavernous Angioma
Brain Cavernous Angioma Characteristics and Features
This disease is characterized by highly dilated blood vessels with a single layer of endothelium and an absence of neuronal tissue within the lesions. These thinly-walled vessels are similar to sinusoidal cavities filled with stagnant blood. Blood vessels in patients with CCM can range in size from a few millimeters to several centimeters in diameter. CCM lesions typically resemble raspberries in external structure. Many patients live their whole life without being aware that they have a cerebral cavernous malformation. Other patients can have severe symptoms like headaches, seizures, paralysis, bleeding in the brain (cerebral hemorrhage, or hemorrhagic stroke), and even death. The nature and severity of the symptoms depend on the location of the lesion in the brain. Approximately 70% of these lesions appear in the supratentorial region of the brain while the remaining 30% occur in the infratentorial region.
Brain Cavernous Angioma Definition
Brain cavernous angioma, also referred to as cerebral cavernous malformation (CCM), cavernous haemangioma, and cavernoma, is a vascular disorder of the central nervous system that may appear either sporadically or display autosomal dominant inheritance.
Brain Cavernous Angioma Prevalence
Cavernous angiomas represent an estimated 1% of intracranial vascular lesions and 15% of cerebrovascular malformations. With the introduction of MRI, cavernous angiomas are currently the most commonly identified brain vascular malformations. In early studies of major autopsy reports, the calculated frequency was 0.02-0.53%. MRI of lesions with the appearance of cavernous hemangiomas provided information that led to a frequency of 0.39-0.9%. The detection of previously unidentified asymptomatic lesions by using MRIs has recently increased the estimated overall prevalence to 0.45-0.9%. Multiple lesions are seen in an estimated 15-33% of spontaneous cases, although one series reported an incidence as high as 50%. Multiple lesions are more commonly found in the familial form, occurring in as many as 73% of patients.
Brain Cavernous Angioma Symptoms and Signs
Clinical symptoms of this disease include focal neurological deficits, recurrent headaches, hemorrhagic stroke, and seizures, but CCM can also be asymptomatic. Diagnosis is most commonly made by accident through routine magnetic resonance imaging (MRI) screening, but not all MRI exams are created equal. It is important that the patient request a gradient-echo sequence in order to unmask small or punctate lesions which may otherwise go undetected. These lesions are also more obvious on FLAIR imaging compared to standard T2 weighing. FLAIR imaging differs from Gradient sequences; rather, it is similar to T2 weighing but suppresses free-flowing fluid signal. Sometimes quiescent CCMs can be exposed as incidental findings during MRI exams ordered for other reasons.