MR diffusion tensor imaging for dynamic evaluation on morphological and functional changes of hind-limb ischemic skeletal muscles in rabbit models of peripheral arterial occlusive disease / 中国介入影像与治疗学

ABSTRACT

Objective: To observe the value of MR diffusion tensor imaging (DTI) for dynamic evaluation on morphological and functional changes of ischemic skeletal muscle in hind limbs of rabbit models of peripheral arterial occlusive disease (PAOD). Methods: PAOD models were established through excision of the full length and branches of right femoral artery with 32 New Zealand rabbits. DTI scanning of bilateral hind-limbs were conducted on the 3rd, 14th, 21st and 28th day after operation (each n=8), and rabbits were sacrificed after DTI, and the skeletal muscles were harvested for pathological examinations. ADC and fractional anisotropy (FA) values were measured and compared, and the pathological manifestations were observed. Results: DWI showed that the operated calf muscles of PAOD rabbits were oedematous and expanded on the 3rd and 14th day after operation, the corresponding area appeared as hyper-intense on ADC maps and reddish on chromatic FA map, the operated side had higher ADC value and lower FA value than contralateral side, especially on the 3rd day after operation (all P0.05). Pathological examinations showed ligated striated muscles swelling, hemorrhage and necrosis on the 3rd and 14th day after operation, especially on the 3rd day. On the 21st day after operation, atrophy of individual striated muscles, hyperplastic and angiectatic interfascicular thick-walled vessels, as well as proliferation of small intermuscular vessels were observed. On the 28th day after operation, swelling cells basically recovered, most of fibroblasts/myofibroblasts were obviously hyperplastic and intercellular space slightly widened. Conclusion: DTI can dynamically and quantitatively evaluate the damage and repair process of ischemia skeletal muscle of hind limbs in PAOD rabbits over time.