Anna Palmisano MD, Presenter: Nothing to Disclose

Antonio Esposito MD, Abstract Co-Author: Nothing to Disclose

Tamara Canu RT, Abstract Co-Author: Nothing to Disclose

Francesco Maria Lo Russo, Abstract Co-Author: Nothing to Disclose

Francesco Aldo De Cobelli MD, Abstract Co-Author: Nothing to Disclose

Alessandro Del Maschio MD, Abstract Co-Author: Nothing to Disclose

Non invasive and quantitative evaluation of muscle damage has important clinical application and a crucial role on preclinical research. Aim was to set up and validate an MR based non-invasive protocol for the quantitative assessment of muscle damage/healing process in murine models of acute ischemic and non-ischemic damage.

MR imaging was performed on a 7T magnet (Bruker): T2w-MSME sequences were acquired for the assessment of T2 relaxation time (T2-rt) and diffusion tensor images (EPI-DTI sequences) for the quantification of the fractional anisotropy (FA), in 24 C57BL/6N mice before intramuscle injection of cardiotoxin (CTX) and after 1, 3, 5, 7, 10, 15, 30 days. The same protocol was acquired 1,3,5,7,14,21 days after femoral artery ligation in 10 mice. Moreover, in these last group of mice DCE-MRI was performed and Ktrans and Ve evaluated. MRI parameters were compared to histological findings at each time point.

After i.m. injection of CTX: T2-rt peaked at day 3 followed by a progressive return to normal values; FA drops at day 1 with a progressive increase over normal values between day 7 and 15. A strong correlation was found between T2-rt and leukocyte infiltrates (r = 0.92 p<0.003), and between FA and the extent of tissue regeneration (% of regenerating fibres) (r = 0.88 p<0.001). In mouse model of acute ischemic damage we observed a trend similar to the previous but with a slower kinetics: T2-rt peaked between day 3 and 7 with a progressive return to basal value; FA drops between day 3 and 5 and reaches values higher than normal after day 14. DCE-MRI study showed a drop of k trans after damage, due to absent perfusion, with a progressive increase over normal value between day 7 and 14, paralleling to vascular regeneration. Ve increased at 24 hr after ischemic damage with a plateau till day 14-21, then return to normal values.

Multiparametric MRI offers an effective and complete evaluation of muscle damage/healing process.In particular,T2-mapping e Diffusion Tensor Imaging allow an accurate quantitative monitoring of inflammatory infiltration and muscle regeneration occurring after acute muscle damage.  

Multiparametric quantitative MRI is a potentially powerful tool for the non invasive assessment of muscle damage/repair process also in clinical fiel.

Palmisano, A, Esposito, A, Canu, T, Lo Russo, F, De Cobelli, F, Del Maschio, A, Non Invasive and Quantitative Evaluation of Muscle Damage has Important Clinical Application and a Crucial Role on Preclinical Research. Aim Was to Set Up and Validate an MR Based Non-invasive Protocol for the Quantitative Assessment of Muscle Damage.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14045797.html