Spontaneous rupture of an intercostal artery in a patient with neurofibromatosis type 1.

A 48-year-old man with neurofibromatosis type 1 (NF1) presented with a right pleural effusion. A 3D computed tomography (CT) angiogram showed an aneurysm of the right 11th intercostal artery. He had no history of chest trauma so we diagnosed a spontaneous rupture of the aneurysm causing a massive effusion. We opened his pleural cavity and found lacerated pleura and active bleeding in the posterior 11th intercostal space. After controlling the active bleeding, we treated a persistent oozing from the region of the 10th-12th vertebrae with pressure hemostasis by absorbable oxidized cellulose packing. The next day, the patient gradually developed a paraplegia affecting both lower limbs. Magnetic resonance imaging (MRI) showed spinal cord compression at the level of the 9th and 10th vertebrae. We evacuated the cellulose and coagulum. The patient's paraplegia improved and within six months he was walking without a crutch.