August 3, 2010


Axial CT image shows a small well-defined hyperdense lesion (arrow) in the gray-white matter junction of the left posterior parietal lobe without evidence of mass effect or surrounding edema.
Axial T2W MR image shows the lesion predominantly high signal intensity with a complete ring of dark T2 signal, suggesting the presence of hemosiderin.

Facts: Cavernoma
  • Low-flow vascular anomaly of the brain
  • Endothelium-lined blood cavities without muscular or adventitial layers. No brain tissues present between these blood cavities
  • May be sporadic, related to prior radiation, or hereditary
  • Patients commonly present with seizures due to internal bleeding
  • Annual bleeding rate between 0.25 to 0.7% per year
  • On follow up, most cavernomas increase in size due to osmotic changes
  • 80% are supratentorium, and size between 1-2 cm
  • Appearance depends on amount of internal thrombosis, hemorrhage and calcification
  • MRI is the modality of choice because it can show various stages of bleeding in the lesion, which is characteristic for cavernoma
  • If presents with acute hemorrhage, CT appearance will be similar to intracerebral hemorrhage of other causes. MRI in acute phase may provide a clue to the diagnosis of cavernoma if it shows various stages of bleeding in particular the presence of hemosiderin
  • If presents incidentally, cavernoma appears as a hyperdense mass without causing mass effect on CT. If calcified, it will be only partially calcified. On MRI, it shows a complete ring of dark T2 signal due to the presence of hemosiderin (this effect is best seen on GRE T2* sequence)

Kuker W and Forsting M. Cavernomas and Capillary Telangiectasias. In: Baert AL, Knauth M, Sartor K. Intracranial Vascular Malformations and Aneurysms, 2nd revised edition, 2008

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