Aneurysm of the major vessels in neurofibromatosis.

The case of a patient who presented with a ruptured aneurysm of the brachial artery and type I neurofibromatosis is presented. Angiography revealed a ruptured aneurysm of the brachial artery in the middle of the upper arm. Repair of the artery with autogenous vein grafting was impossible due to the extremely brittle brachial artery and accompanying veins. The blood supply distal to the aneurysm was secured by collaterals, and the aneurysm, including a relatively long portion of the brachial artery and veins adjacent to the aneurysm, was resected. The patient died of massive hemorrhage from the subclavian artery of the involved side 9 days postoperatively. Histological and immunohistological examinations of the tissues involved in the ruptured aneurysm were conducted. The resected brachial artery and veins were surrounded by hypertrophied tissue which tested positive for S-100 protein and negative for desmin and action. These findings suggest that the origin of the proliferating tissue was not mesodermal dysplasia, but neurofibroma occurring near or in the vessels. A ruptured aneurysm in a patient with neurofibromatosis should not be treated with reconstruction of the vessels. The treatment of choice is surgical or endovascular occlusion of the vessels involved.