Perfusion measurements of the calf in patients with peripheral arterial occlusive disease before and after percutaneous transluminal angioplasty using MR arterial spin labeling.

PURPOSE: To evaluate muscle perfusion in patients with peripheral arterial occlusive disease (PAOD) before and after percutaneous transluminal angioplasty (PTA) of the limb by means of MR arterial spin labeling (ASL) perfusion measurements during reactive hyperemia. MATERIALS AND METHODS: Ten patients with symptomatic PAOD affecting the iliac or femoral vessels were investigated before and after PTA. A pseudo-continuous arterial spin labeling (PCASL) MR technique was applied. Perfusion was measured in soleus and tibialis anterior muscle during reactive hyperemia. Key parameters such as mean perfusion value (Phyp ), time-to-peak (TTP) and duration of hyperemia (Thyp ) describing the perfusion signal curve were examined. RESULTS: Between baseline and post-PTA, Phyp increased in both muscle groups. At the same time, TTP and Thyp decreased in both muscle groups. At the same time the clinically assessed ankle brachial index (ABI) increased from 0.56 ± 0.10 to 0.83 ± 0.15. The impaired pain-free walking distance improved in all patients. CONCLUSION: PCASL MRI can detect changes of the key perfusion parameters Phyp , TTP, and Thyp after successful PTA of the calf muscles during reactive hyperemia and seems to be a promising tool for monitoring of interventional treatments.