Positive outcome after endoscopic treatment of a symptomatic convexity arachnoid cyst in an elderly

Cerebral convexity arachnoid cysts (ACs) only represent around 10–14% of the cysts. Symptomatic ACs in the elderly are rare. We present a 66-year-old woman with headache and a focal epileptic seizure. Imaging revealed a left parietal AC. Conservative management chosen but the patient’s neurological condition worsened, and an endoscopic fenestration was then performed. Postoperatively, her symptoms completely resolved and MRI image showed significant shrinkage of the AC.