CBL: Cerebral Vascular Malformations

Learning Objectives

• Review the four major cerebral vascular malformations: cavernous malformation, capillary telangiectasia, AVM, and DVA.
• Recognize that cavernous malformations carry a small risk of spontaneous hemorrhage.
• Understand that management ranges from observation to surgery, depending on lesion type and symptoms.

Vignette

KA is a 26-year-old woman with sudden, severe bilateral retro-orbital headache. No typical migraine features (no photophobia or nausea). No fever or sinus symptoms; denies facial numbness or diplopia; mild dizziness is present but less concerning than pain. Meds: oral contraceptive. PMH: one prior pregnancy; no drug allergies. She does not smoke or drink. Ten-system ROS is negative.

Examination

T 99.3°F, BP 125/78, HR 78; no orthostasis. Alert on ER gurney; cardio/carotid exams normal. Pupils/fundi normal. Vertical nystagmus on upgaze; other eye movements normal. No scalp tenderness. Cranial nerve exam otherwise normal. Strength, reflexes, coordination, Romberg, and gait are normal.

Localization & Neuroanatomy

Retro-orbital pain is poorly localizing (trigeminal ganglion, cavernous sinus, paranasal sinuses, retro-orbital spaces). Vertical nystagmus suggests involvement of vertical gaze centers in the dorsal midbrain or cerebellum, prompting evaluation of posterior fossa and midbrain structures.

Diagnosis

Acute severe headache without benign features warrants neuroimaging. CT can miss midbrain/cerebellar peduncle lesions; MRI brain is preferred here. Four congenital cerebrovascular malformations may be identified:

• Cavernous malformation (cavernoma): clusters of sinusoidal vessels; often small/multiple; annual hemorrhage risk ≈1–2% and higher with prior bleed; symptomatic lesions often considered for surgery; incidental lesions commonly observed.
• Developmental venous anomaly (DVA): common collateral draining vein; best seen with contrast; usually asymptomatic; generally observed, though rare cases undergo surgery.
• Arteriovenous malformation (AVM): direct artery–vein shunt; may cause headaches, seizures, focal deficits, or hemorrhage; typical annual bleed risk around 2% for moderate lesions; management individualized—sometimes surgery to lower hemorrhage risk.
• Capillary telangiectasia: small enhancing blush on MRI; typically clinically silent with no hemorrhage risk; observation is standard.

Treatment

Most congenital malformations (especially DVA and capillary telangiectasia) require no intervention and are observed clinically. Symptomatic cavernomas are often evaluated for resection; AVMs may be managed with microsurgery, endovascular therapy, and/or stereotactic radiosurgery depending on size/location and symptoms. Radiosurgery is frequently considered for brainstem/cerebellar cavernomas that are not amenable to open surgery.

Teaching Points

• Vertical nystagmus should trigger MRI targeted to dorsal midbrain/cerebellum.
• Cavernomas: small but real annual hemorrhage risk (~1–2%); recurrence risk higher after a bleed.
• DVAs and capillary telangiectasias are usually incidental and observed.
• Management of AVMs and symptomatic cavernomas is nuanced and may involve surgery or radiosurgery.

References

1. Module adapted from provided teaching text on cerebral vascular malformations, emphasizing imaging approach and management strategies.