Abstract
Neurofibromatosis type 1 (NF1), also known as von Recklinghausen disease, is the most common phacomatosis. It is characterized by neurofibromas but also manifests vascular complications including stenosis, arterial ectasia, and aneurysms. We report the case of an otherwise healthy 45-year-old male who developed a fatal tension hemothorax due to bleeding from the left costocervical artery. Tension hemothorax without trauma is rare except in cases with a rupture of an aortic aneurysm; we successfully treated the patient by promptly diagnosing tension hemothorax and performing chest drainage, as well as timely transcatheter arterial embolization (TAE) to control bleeding. When encountering shock patients with NF1, clinicians should be mindful of the potential for non-traumatic hemorrhagic complications due to vascular malformation.