Endoscopic Clipping of a Middle Cerebral Artery Aneurysm in a Middle Fossa Arachnoid Cyst and Review of the Literature

Background: Arachnoid cysts are often associated with subdural hematoma following head trauma. The incidental finding of an aneurysma and a cyst is rare. We describe for the first time the treatment of such a case using endoscopic techniques. Case Report: A 44-year-old man was admitted to our hospital with a mild headache and a hemifacial spasm attack at the right side of his face. The radiological examinations demonstrated bilateral slyvian fissure arachnoid cysts and an aneurysm with the dome projecting superolaterally, at the bifurcation of the right middle cerebral artery in the arachnoid cyst. The patient underwent a complete endoscopic surgical clipping of the aneurysm, and partial excision of the right cyst wall and bilateral fenestration to the basal cistern via a single burr-hole craniectomy at the right temporal region. The patient had an uneventful postoperative course without neurological impairment and complication. However, his complaints still persisted postoperatively. Conclusion: Endoscopic management of arachnoid cysts is an effective and less morbid treatment. This less invasive option might be safe for the clipping of aneurysms within an arachnoid cyst with no additional morbidity for the patient. With smaller operative exposures and yet better visualization offered, neuroendoscopy may reduce operative morbidity.