[Chronic Subdural Hematoma with Middle Cranial Fossa Arachnoid Cyst Concomitant with Bilateral Papilledema:A Case Report].

Arachnoid cysts(AC)are benign cystic lesions often diagnosed in childhood. Although usually asymptomatic, AC can become symptomatic when the lesion size increases or coexists with a subdural hygroma or hematoma. AC patients with signs of increasing intracranial pressure(IICP)or neurological deficits may need surgical intervention; this usually results in a good prognosis. However, whether asymptomatic AC patients should undergo surgical treatment is controversial. Although trivial head trauma, such as that from contact sports, can cause subdural hematoma in AC patients, there are currently no definite criteria regarding sports participation for children with AC. CASE: A 12-year-old boy who belonged to a soccer club visited an ophthalmologist with the chief complaint of having had diplopia for two weeks. He was identified as having bilateral papilledema. Since he had been diagnosed with a right middle cranial fossa AC five years earlier, he was referred to our outpatient clinic. Cranial CT scans showed right chronic subdural hematoma alongside the AC. The patient subsequently underwent burr hole surgery and was discharged after one week. In this case, the patient did not present with the typical signs of IICP, such as headache or vomiting. This experience indicates that care must be taken when encountering patients with atypical symptoms, particularly children. In addition, it is important to carefully consider sports participation for children with AC.