A rabbit model of acute spinal cord compression injury by rapid exchange balloon dilatation catheter

English Keywords:Spinal cord injuries  Spinal cord compression  Rapid exchange balloon dilatation catheter

English Abstract:

  【Abstract】 Objectives: To investigate the operation process and effect of rapid exchange balloon dilatation catheter to induce the model of acute spinal cord compression injury(SCI). Methods: Spinal cord compression injury model was introduced in 24 New Zealand white rabbits. The models were randomly divided into 3 groups. A 4cm median incision was taken to expose T8 to T11 after narcosis, then a side of T8 vertebral plate was removed. Rabbits in group A only received the laminotomy without insertion of balloon; in group B, the balloons were surgically positioned in the T10 spinal canal but not inflated; in group C, the balloons were put through T8 into T10, and the spinal cords were compressed by inflating the balloon to reduce about 30% of anteroposterior vertebral canal diameter. Computed tomography(CT) was used to show the location of balloon and kept the record of all the pressure for 48h. The modified Tarlov motor function grade test and SSEP were applied to evaluate the motor function of hind limbs before and at 48h after surgery. Then the weight loss and dietary were recorded change every day. Finally, 5 rabbits from each group were randomly selected and spinal cord in the center of T10 was taken out to take the histological examination. The pressure in balloon was reduced to negative pressure before taking out the balloons in group B and group C, the other 3 cases in each group continued to be taken the weight loss and dietary change at 4d, 7d, 14d after operation. Results: The 95% confidence interval of pressure was 48.55-85.91kPa(mean, 67.23±22.34kPa) in group C. The SSEP showed that motor function was seriously damaged in group C. The SSEP in group C after surgery was significantly different from group A and B(P<0.05). However, the SSEP did not show statistically difference between group A and B(P>0.05). The differences of weight loss and dietary change at 1d, 2d, 4d, 7d, 14d after operation were not statistically significant among the 3 groups(P>0.05). The weight recovered to normal at the 14th of day post-operation. The diet returned to normal at 7d of post-operation. While group C had lower modified Tarlov motor function grade than group A and B(P<0.05). The difference of modified Tarlov motor function grade was not statistically significant between group A and B(P>0.05). Conclusions: A model of acute spinal cord injury by using the compression with rapid exchange balloon dilatation catheter is successfully induced. It can well simulate the clinical situations of SCI.