Cavernous Malformation

Diagnosis Definition

• Cavernous malformations (also known as cavernous angioma/hemangioma, cavernous venous malformation, or cavernoma) are the second most common intracranial vascular malformation; they are considered to be congenital
• They are slow-flow, low-pressure vascular malformations with no normal intervening brain parenchyma
• Most lesions are asymptomatic; seizures are the most common form of presentation when symptomatic; the risk of bleeding is 1-2% annually

Imaging Findings

• Characteristic features on MRI include a reticulated pattern of mixed hyper- and hypointensity on T1- and T2-weighted imaging (so-called “popcorn” or “mulberry” appearance due to multiple episodes of hemorrhage), and a hypointense rim of hemosiderin surrounded by blooming artifact, best appreciated on T2-weighted or susceptibility-weighted imaging (SWI)
• If a recent bleed has occurred then surrounding edema may be present
• The lesions generally do not enhance, although enhancement is possible

KEY IMAGES

Pearls

• Multiple cavernous malformations can be seen when there is a familial component or in the setting of postradiation therapy
• T2-weighted SWI sequences, with their increased magnetic susceptibility effects, should always be performed during an evaluation for smaller or multiple lesions that may not be visible on fast spin-echo images

References

1. Rigamonti D, Drayer BP, Johnson PC, Hadley MN, ZabramskiJ, Spetzler RF. The MRI appearance of cavernous malformations (angiomas). J Neurosurg 1987; 67(4):518-524