Name : Morteza
Family : Sanei Taheri
Affiliation :Radiology department,ShohadaTajrish Hospital,SBMU
Academic Degree : Associate professor of Radiology
Resident : Maryam Sheikh
Gender : Male
Age : 36
A 36 Y/O man with uncontrolled seizure on anticonvulsant therapy
CT scan demonstrates Serpentine density with punctate calcification in Rt frontal lobe. DSA demonstrates a high flow AVM in the Rt frontoparietal area of Rt hemisphere with multiple dilated feeding vessels from Rt MCA,Rt PCA and Lt ACA and multiple draining veins.
Vein of Galen malformation
Discussion (Related Text)
Arteriovenous malformations (AVMs) are congenital lesions composed of a complex tangle of arteries and veins connected by one or more fistulae. AVMs tend to be clinically silent until the presenting event occurs; therefore, the diagnosis usually is made at the time of the first seizure or hemorrhage.A history of minor learning disability is found in as many as two thirds of patients.A history of headaches is found in as many as half of all patients with cerebral AVM; the headaches subsequently may take the form of classic migraine or more generalized headache. The following imaging studies are used in the diagnosis and assessment of cerebral AVM:
Computed tomography (CT) scanning: Easily identifies intracerebral hemorrhages, raising suspicion of AVM in a younger person or a patient without clear risk factors for hemorrhage; however, this modality can identify only large AVMs.
Magnetic resonance imaging (MRI): Essential for the initial diagnosis of AVMs; the malformations appear as irregular or globoid masses anywhere within the hemispheres or brainstem.
Cerebral angiography: Required for hemodynamic assessment, which is essential for planning treatment
Superselective angiography: Performed with standard cerebral angiography, with access via a femoral artery puncture
Invasive treatment is recommended for younger patients with 1 or more high-risk features for an AVM rupture.Invasive treatment of AVMs may include endovascular embolization, surgical resection, and focal beam radiation, alone or in any combination.
AVMs may be cortical, subcortical, or in deep gray or white matter.
Small, round, low-signal spots within or around the mass on T1, T2, or fluid-attenuated inversion recovery (FLAIR) sequences are the "flow voids" of feeding arteries, intranidal aneurysms, or draining veins.
If hemorrhage has occurred, the mass of blood may obscure other diagnostic features, requiring angiogram or follow-up MRI.
Low signal of extracellular hemosiderin may be seen around or within the AVM mass, indicating prior symptomatic or asymptomatic hemorrhage.
Larger aneurysms within the AVM or on feeding arteries may be identified occasionally.
Magnetic resonance angiography (MRA) may identify AVMs greater than 1 cm in size,but is inadequate to delineate the morphology of feeding arteries and draining veins; small aneurysms can be missed easily.