Middle cerebral artery dissecting aneurysm causing intracerebral hemorrhage 4 years after the non-hemorrhagic onset: a case report.

Background: We report a case of dissecting middle cerebral artery (MCA) aneurysm causing intracerebral hemorrhage 4 years after the non-hemorrhagic onset.

Case Description: A 30-year-old male was diagnosed with an unruptured dissecting MCA aneurysm after a severe pulsating headache in August 1993. Angiography revealed dilatation of the distal portion of the temporo-occipital artery. During 2 years of follow-up, there were no significant changes on magnetic resonance imaging. In August 1997, he became comatose because of massive intracerebral hemorrhage caused by a dilated fusiform dissecting aneurysm. Emergency surgery and postoperative mild hypothermia resulted in full recovery.

Conclusion: To date only 30 cases of dissecting MCA aneurysm have been reported and for unruptured aneurysms, surgical intervention was not chosen. However, the present case strongly suggests that long-term follow-up is necessary in patients with unruptured dissecting aneurysms of the anterior circulation, especially those with ectatic components.