Hi, your brother has arachnoid cyst L) temporal lobe.Arachnoid cysts are cerebrospinal fluid covered by arachnoidal cells and collagen that may develop between the surface of the brain and the cranial base or on the arachnoid membrane, one of the three membranes that cover the brain and the spinal cord. Arachnoid cysts are a congenital disorder Your brother has to continue trioptal .Dose of drug has to be titrated as per body weight and clinical symptoms ( headache and seizure).Maximum dose is 40mg/kg body weight.If seizure occur with maximum dose then second antiepileptic drug has to be added.He require serial CT scan brain every 6 months to asses the size of arachnoid cyst, any temporal lobe hypo development , any hemorrhage or mass effect. In view of structural lesion he requires life long medicine. Most arachnoid cysts are asymptomatic and do not require surgical treatment. Treatment may be necessary when symptomatic. A variety of procedures may be used to decompress (remove pressure from) the cyst. Surgical placement of a cerebral shunt: An internal shunt drains into the subdural compartment. A cystoperitoneal shunt drains to the peritoneal cavity. Fenestration: Craniotomy with excision Various endoscopic techniques are proving effective,including laser-assisted techniques. Drainage by needle aspiration or burr hole. Capsular resection Regards Dr Sandhya Manorenj Neurologist Hi Tech city, Hyderabad