Sensitivity of radionuclide brain imaging and computerized transaxial tomography in detecting subdural hematoma.

In a series of 23 patients with surgically proven subdural hematoma of durations ranging between two days to seven months, the detection rate of Tc-99m-pertechnetate brain imaging was higher than computerized transaxial tomography (CT). With dynamic perfusion scanning, the detection rate was 71.5%. However, when combined with sequential static images obtained at 10 minutes, 2 hours and 3--4 hours, the detection rate rose to 92% regardless of the duration of the disease. In contrast, CT demonstrated the hematoma in 52% of the cases. In another 28% the diagnosis was suggested through nonconclusive evidence or presence of contralateral shift of midline structures. Lastly, the result of CT scanning was dependent on the size of the subdural hematoma as evaluated at the time of operation.