[Bilateral chronic subdural hematoma with communication between the hematoma cavities: report of an adult case].

The authors present a case of bilateral chronic subdural hematoma with communication between the hematoma cavities. This 24-year-old male had hit his forehead while playing football and visited our hospital. An initial plain CT scan revealed extracerebral low density areas in the bifrontal region, which were considered to be post-traumatic subdural hygromas. The lesion was followed up with repeat CT scans. On plain CT scan performed seven weeks after the injury, the lesion had evolved into bilateral chronic subdural hematoma and the patient was admitted to our ward. He underwent burr hole drainage on the left side, because the hematoma volume on the left side was considerably larger than that on the right side. A plain CT scan on the day following the operation revealed complete resolution of the hematomas on both sides. A favorable re-expansion of the brain was confirmed on consecutive CT scan performed two months after the operation. In general bilateral chronic subdural hematomas in adults are considered to have no communication between the hematoma cavities and therefore they should be evacuated on both sides simultaneously. In our case, on the contrary, the operation revealed a communication between the hematoma cavities. The falx cerebri is narrow in front and this narrow anterior part is frequently perforated by one or more apertures. We attributed the communication to this anatomical feature of the falx cerebri. On preoperative CT scan, in addition, the inner surface of the bifrontal hematoma cavity demonstrated a smooth concave figure indicating retrospectively that the cavity on the left side was continuous with that on the right side.(ABSTRACT TRUNCATED AT 250 WORDS)