Experimental Study Of DTI Combined With PAF On Evaluation Of Acute Spinal Cord Injury

Objective: DTI combined with PAF were used to study a model of acute spinal cord injury on rabbits, in order to to further explore the evaluation value of DTI on acute spinal cord injury.Methods: 30 healthy, adult Chinese rabbits, regardless male or female, weight 2.5 ± 0.3 kg, age 3-4 months,24 were randomly selected as experimental group(divided into 1d, 3d, 5d, 7d four time points, each time point 6), and the other 6 as control group. The Allen’s method was used to simulate the moderate acute spinal cord injury on the experimental group, and the control group only cut the muscle on the back, exposed the spinal cord, and did not damage the dura mater spinalis. After 1d, 3d, 5d and 7d, the regular MRI and DTI scans were respectively done, then to assay serum PAF concentration and pathological examination after the scanning. The FA and ADC values were measured by image post-processing software. At last, the FA and ADC values were compared with the pathological examination results and serum PAF concentration.Results: 1.PAF results: compared with the control group, serum PAF concentration of the experimental group was significantly increased(P<0.01). Compared with the experimental group in 1d : serum PAF concentration was obviously increased in 3d, 5d, 7d(P<0.01); Compared with the experimental group in 3d : serum PAF concentration was obviously increased in 5d,7d(P < 0.01); Compared with the experimental group in 5d: serum PAF concentration was obviously increased in 7d(P<0.01).serum PAF concentration of the control group didn’t have any change at each time. 2.Pathological findings: there was no abnormal pathological characteristics in the spinal cord of the control group. In the experimental group, the edema, hemorrhage and tissue necrosis of spinal cord injury were obvious, and showed different pathological changes with the elapse of time. Inflammatory cells began to increase at 1d, reached its peak at 5d, decreased at 7d. Compared with the control group:the number of large motor neurons decreased significantly in the experimental group at each time point(P<0.01). With the passage of time, the number of large motor neurons showed a decreasing trend in experimental group,there is a significant difference(P<0.01). 3.DTI parameters measurement results: compared with the control group, the ADC value of the experimental group was significantly increased and the FA value was significantly decreased in each time point(P<0.01). Compared with the experimental group in 1d : the ADC value was obviously increased and the FA value was obviously decreased in 3d, 5d, 7d(P<0.01); Compared with the experimental group in 3d : the ADC value was obviously increased and the FA value was obviously decreased in 5d, 7d(P<0.01); Compared with the experimental group in 5d : the ADC value was obviously increased and the FA value was obviously decreased in 7d(P < 0.01).The ADC value and the FA value of the control group didn’t have any change in each time(P>0.05). 4.Correlation analysis of experimental group: Related Pearson: PAF value was positively correlated with ADC value in 1d, 3d, 5d; negatively correlated with ADC value in 7d( |r|>0.8, P<0.05) and it was negatively correlated with FA value in 1d, 3d, 5d, positively correlated with FA value in 7d( |r|>0.8, P<0.05). The number of inflammatory cells were negatively correlated with FA value in 1d, 3d, 5d and positively correlated with FA value in 7d( |r|>0.8, P<0.05),and it was positively correlated with ADC value in 1d, 3d, 5d and negatively correlated with ADC value in 7d( |r|>0.8, P<0.05); the horn motor neurons in spinal cord anterior were positively correlated with FA value in1 d, 3d, 5d, 7d( |r|>0.8, P<0.05),and showed a negative correlation with ADC value in 1d, 3d, 5d, 7d( |r|>0.8, P<0.05).Conclusion:1.FA value, ADC value have a good correlation with PAF. 2.FA value, ADC value have a good correlation with number of inflammatory cells and motor neurons in spinal cord large anterior horn. 3.DTI can be used as one of the non-invasive evaluation methods of acute spinal cord injury.