Presenting symptoms in 4 patients with acute benign cerebral angiopathy were headaches over several days, with a transient neurologic disorder in two cases. Angiography showed diffuse and segmental distal narrowing alternating with dilatations. In one patient, the radiologic anomalies persisted to a milder degree in the same region 2 months later, while the reduced cerebral blood flow failed to return to normal. The pathophysiology of this syndrome would appear to result initially of vasospasm in particularly reactive subjects, especially young women. Its cause appears to vary from one case to another: post-partum disorders, infection or inflammation, meningeal hemorrhage, paroxysmal hypertension. Adjuvant factors could be unusual effort, medication or a migraine context. In spite of this pathogenetic uncertainty this angiopathy in usually considered as an isolated, benign and non-relapsing disease.