A Preliminary Research On The Acute Ischemic Rhabdomyolysis Of Rabbits By MRI

Objective:To establish model of acute ischemic rhabdomyolysis in rabbit hindlimb; To investigate the value of MRI early diagnosis and value extent and scope of rabbit rhabdomyolysis; To provide the experimental reference for Clinical application of MRI to determine amputation treatment indications.Methods:34 rhabdomyolysis models of New Zealand white rabbits, are established Preoperative and postoperative 1 hour, after 2 hours, after 3 hours, after 4 hours, after 5 hours, after 6 hours, after 7 hours were carried out T1WI, T2WI-fat suppression, T2map, DTI scans, and do post-processing image, T2 values and ADC values were obtained. Respectively, do biopsy in vastus lateralis and creatine kinase, lactate dehydrogenase, creatinine and lactate testing, before surgery or/and after scaning。By statistical analysis, comparing the relevant indicators to determine the different situation of ischemic side and contralateral side, with times.Results:①Rabbit hindlimb model of acute ischemic rhabdomyolysis technical success rate of 100%。②After 7 hours, creatine kinase (CK), lactate dehydrogenase (LDH) values were significantly higher than before (P<0.01). Creatinine, lactate values were higher than before (P <0.05)③Pathological results: the ischemic side was no significant difference before 6 hours,occurred granular degeneration after 6 hours, occurred fuzzy rhabdomyolysis after 7 hours.④MRI results:the ischemic side signal of T2-fat suppression sequently appeared to increase after 2 hours; the ischemic side signal of T1WI than the contralateral side was slightly higher after 7 hours, the ischemic side signal of T2WI-fat suppression showed high signal after 7 hours; the ratio of T2 values of the Ischemic side and the contralateral side correlate linearly with time in 1-6 hours, declined from 6 hours (P<0.05). the ratio of ADC values correlate linearly with time in 1-5 hours, declined from 5 hours (P<0.05).Conclusion:①Muscle pathology confirmed:rabbit vastus lateralis appears rhabdomyolysis after completely ischemic 7 hours.②MRI signal changes of rhabdomyolysis directly related to the edema; arise from ischemic phase to the occurrence of rhabdomyolysis, edema associated with them; the ischemic side signal of T2-fat suppression sequently appeared to increase after completely ischemic 2 hours.③T2 values can be quantified to reflect the water molecules situation in striated muscle, a decline from completely ischemic 6 hours shows the content of the water molecules change, there rhabdomyolysis; ADC values can be quantified to reflect the molecules situation in striated muscle, a decline from completely ischemic 5 hours, shows the degree of water molecules diffusion changes, upcoming rhabdomyolysis.④T2 values and ADC values reflect the changes of the edema situation, may indirectly reflect rhabdomyolysis; this provides a new choice for clinical application of MRI; MRI can early diagnosis and assess the extent and scope of rhabdomyolysis, to determine the amputation treatment indications.