The study aimed to follow the effects of purely extradural spinal cavernous malformations (ESCMs). A 44-year-old woman presented with progressive cervicothoracic back pain, lower limb paraesthesia, and hypertonia. MRI showed a well-circumscribed, convex lesion in the T1-4 extradural space causing cord compression and creeping into the left T2/3 neural foramen. Selective spinal angiography demonstrated a vascular blush at the T2/T3 level corresponding with the mass. A feeding vessel from the base of the T1 spinous process was identified and successfully catheterized, but embolization was precluded by the posterior spinal artery’s unfavorable anatomy. At hemilaminectomy, the lesion was found to be an ESCM. The patient went on to make a full recovery. We reviewed 71 cases of ESCM reported in the last decade.

The incidence of ESCM is unclear; the most extensive case series reported on nine patients, but most published accounts were single case studies. Patients presented with back pain, myelopathy, and radiculopathy. The onset of symptoms was usually insidious over months to years, but 30% presented with sudden-onset neurological symptoms, often due to spontaneous bleeding. All patients underwent total or subtotal microsurgical resection with excellent results; all improved or recovered fully after surgery. Those who presented acutely did worse; 38% had residual deficits.