A young adult with severe headache has a non-contrast CT showing a small round hyperdense lesion in the right sylvian fissure region with surrounding edema. MRI shows a 'popcorn-like' lesion with a hemosiderin rim and mixed signal core. The diagnosis is:

• A Dural arteriovenous fistula
• B Capillary telangiectasia
• C Developmental venous anomaly
• D Cavernous malformation (cavernoma) ✓

Explanation

Cavernous malformations (cavernomas) classically show a 'popcorn' or 'mulberry' appearance on MRI with a heterogeneous core due to blood products at different stages of evolution (met-hemoglobin, hemosiderin) surrounded by a complete hemosiderin rim (low signal on T2/T2*). They appear hyperdense on non-contrast CT due to calcification and acute blood. They have no arteriovenous shunting and are angiographically occult. Developmental venous anomalies show a 'caput medusae' pattern of venous drainage without hemosiderin rim.

Reference: Grainger & Allison's Diagnostic Radiology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.