Spontaneous healing of an isolated posterior inferior cerebellar artery dissection without stroke: a case report

Isolated posterior inferior cerebellar artery dissections can cause subarachnoid hemorrhages or infarctions. Surgical and endovascular treatments for hemorrhagic stroke cases and medical treatments using antithrombotic agents for ischemic stroke cases have been performed, but there are very few reports on nonstroke isolated posterior inferior cerebellar artery dissections, and the treatment strategy for nonstroke cases has not been established.

A 48-year-old healthy male felt a severe, throbbing headache on the right side and came to our clinic on the fourth day following onset. MRI examinations revealed a right posterior inferior cerebellar artery dissection and showed no infarctions or hemorrhages. He was observed carefully with continuous monitoring of blood pressure, hydrated sufficiently, and given analgesic anti-inflammatory agents. Two weeks later, the dissected vessel’s diameter grew to the maximum size, though the patient’s headache rapidly improved around that day. Surgical or endovascular treatments for prevention of subarachnoid hemorrhage were recommended, but careful conservative therapy was continued in accordance with the patient’s wishes. Gradually, the dissection finding improved. Four months later, MRI examinations showed his right posterior inferior cerebellar artery was almost normal in size and shape.

This is the first detailed report on a nonstroke isolated posterior inferior cerebellar artery dissection that spontaneously occurred and healed, observed by serial high-resolution MRI examinations.