Conus Medullaris Avm; A Case Presentation Of A Spinal Intramedullary Tumor Mimic

Abstract

INTRODUCTION: Spinal arteriovenous malformations (AVMs) are rare vascular lesions of the spinal cord, accounting for 3-4% of spinal cord masses.(Figure1). Arteriovenous malformations located in the conus medullaris region are particularly rare, with an even lower incidence reported among pediatric patients.  These lesions frequently mimic intramedullary tumors, especially ependymomas, in clinical presentation and MRI characteristics. This resemblance complicates accurate diagnosis and appropriate management. Timely and precise diagnosis is essential to prevent inappropriate therapeutic interventions and to minimize the risk of irreversible neurological deficits. Endovascular embolization is employed to achieve targeted arteriovenous malformation (AVM) closure. CASE PRESENTATION: An 11-year-old girl presented with a month history of sudden onset bilateral lower limb weakness with reduced sensation and inability to walk. She had associated urinary incontinence. Examination revealed a girl in a fair general condition.  She had normal spine contour along the lumbar spine, no deformities, and a normal range of motion. Motor findings revealed bilateral lower limb weakness with power grade 3. Laboratory tests were Hgb 13.2 g/d and a normal WBC of 5,970 cells/uL. MRI of the spine showed an intramedullary lesion at the conus medullaris region with heterogeneous enhancement. Cord swelling and edema around the lesion. Presence of flow voids or serpiginous vessels indicating abnormal blood flow, suggestive of AVM. TREATMENT: The patient had spinal laminectomy and tumor excision. Intraoperative findings were dilated tuft complex networks of vessels. OUTCOME AND FOLLOW UP: She responded well to surgery with a notable improvement of power to grade 4. She was discharged home to continue with occupational therapy and physiotherapy. Currently on  follow-up to monitor and prevent recurrence or further neurological deficits