A case of juvenile chronic encapsulated intracerebral hematoma requiring differential diagnosis, successfully treated with craniotomy and hematoma evacuation.

Background: Chronic encapsulated intracerebral hematoma (CEIH) is a rare condition with an unclear pathogenesis. Moreover, no consensus has been established regarding its treatment. Here, we report a case of juvenile subcortical CEIH successfully treated with complete resection, including the capsule.

Case description: A 26-year-old woman with no notable medical history had experienced headaches for 2 months and 3 weeks before presentation and underwent extraction of the right third molar 1 week before admission. She presented to our hospital complaining of a headache. Visual field testing revealed left upper quadrantanopia. Head CT showed a 5 cm ring-shaped hyperdense lesion in the right temporal lobe, and cerebral angiography revealed no significant vascular abnormalities. On hospital day 10, she underwent craniotomy and removal of the lesion. Intraoperative findings revealed that the hematoma was encapsulated, and en bloc resection was achieved. Histopathological examination showed fibrous connective tissue with fibroblast proliferation covering a hematoma composed of fibrin and red blood cells, consistent with CEIH. The postoperative course was smooth, no new neurological deficits were observed, and both the headache and visual field disturbance improved. She was discharged home 2 weeks after surgery.

Conclusion: Although the pathogenesis of CEIH remains unclear and there is no consensus on treatment, complete resection, including the capsule, was considered the appropriate therapeutic approach in this case, given reports of recurrence and poor outcomes associated with residual capsule tissue or coexistence with cavernous malformations.