Presentation
Seizure.
Patient Data
Age: 10 years
Gender: Female
From the case:
Cavernous malformation of the corpus callosum
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- T1WI: "popcorn ball" appearance of mixed hyper/hypointense blood-containing locules
- T2WI: reticulated popcorn-like lesion most typical, mixed signal core, complete hypointense hemosiderin rim
- T2* GRE: prominent susceptibility effect (hypointense "blooming")
Case Discussion
Diagnosis: cerebral cavernous malformation
Terminology
- represents a benign vascular hamartoma
- contains masses of closely apposed immature blood vessels ("caverns"), no neural tissue
- intralesional hemorrhages of different ages
- exhibit a range of dynamic behavior (enlargement, regression, de novo formation)
Imaging
- vary from microscopic to giant (> 6 cm)
- locules of variable size contain blood products at different stages of evolution
- variable appearance depending on hemorrhage/stage
-
Zabramski classification
- type 1 = subacute hemorrhage (hyperintense on T1WI; hyper-/hypointense on T2WI)
- type 2 = mixed signal intensity on T1, T2WI with degrading hemorrhage of various ages (classic "popcorn ball" lesion)
- type 3 = chronic hemorrhage (hypo- to iso on T1, T2WI)
- type 4 = punctate microhemorrhages ("black dots"), poorly seen except on T2* sequences
- angiography is usually normal ("angiographically occult vascular malformation") unless the lesion is extradural
Differential considerations include:
- arteriovenous malformation
- hemorrhagic neoplasm
- calcified neoplasm
- hypertensive microbleeds
- cerebral amyloid angiopathy