[Experimental study of acute spinal cord injury: a study of spinal blood flow]

It is well known that the worsening of neurological findings after spinal cord injury is due to the secondary progression of pathological changes which may be caused by spinal cord blood flow disturbance. We measured spinal blood flow of 5mm rostrally and caudally distant portions from the injured point, using the laser Doppler flowmeter experimentally. Forty rats were used. Ten of these were used as a control group. And thirty animals were injured at the level of the tenth thoracic cord with a 50g epidural one minute compression method and measured continuously from 30 minutes before the injury to 6 hours after the injury. Twenty two surviving animals were evaluated. In the control group, spinal blood flow was stable. But in the injured group, spinal blood flow dropped by 30.6 + 9.8% on the rostral side and 37.3 + 17.6% on the caudal side in comparison with the resting value soon after the injury. Although the flow improved to 89.3 + 11.1 and 71.3 + 17.8% respectively 15 minutes later, it dropped again gradually and reached 42.8 + 14.1 and 66.2 + 16.4% respectively 6 hours after the injury had been inflicted. Lastly, in the animals, carbon perfusion was performed through the left ventricle. The normal figured vasculature in the preparation of the injured and measured portion was calculated with a microcomputer imaging analyzer and compared with control groups. The number of the normal vessels was significantly more abundant on the caudal side than on the rostral side (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)