Abstract
Both the cortico-spinal MEP and cortico-muscular MEP, which directly reflect the pyramidal function, were recorded in 25 cases of hypertensive intracerebral (putaminal) hematoma. In all cases, over 70% of the hematoma was aspirated by a CT-guided stereotaxic operation within 72 hours of onset. The effects of hematoma aspiration on the cortico-spinal MEP and the corticomuscular MEP were also evaluated.
The D-wave of the cortico-spinal MEP was recordable in 19 cases, while the other 6 cases showed no response before aspiration of the hematoma. Among these 19 cases, 15 revealed an increased amplitude and/or shortened latency of the D-wave after aspiration of the hematoma. The long-term prognosis for motor function was good in cases that showed a D-wave of the cortico-spinal MEP; however, it was bad in the 6 cases that had no D-wave. A magnetic transcranial cortico-muscular MEP was recordable in only 8 cases, while the other 17 cases exhibited no response before aspiration of the hematoma. The D-wave of the cortico-spinal MEP was recordable in all cases of grades 1-5 and in 1 case of grade 0 by the muscle maneuver test (MMT); however, no magnetic transcranial cortico-muscular MEP was recordable in all cases of grades 0-2 and in half the cases of grade 3.
The present results suggest that hematoma aspiration effectively reduces the compression effects of a hematoma against the pyramidal tracts, and that monitoring of the cortico-spinal MEP is useful for assessing the prognosis of the motor function. Further, the cortico-spinal MEP has advantages for assessing the motor function as compared with the magnetic cortico-musular MEP.
