Figure 4.

BOLD-CMR T2* Signal Changes

(A) Mean signal intensity time course curves for the 5 muscle groups (anterior, lateral, soleus, gastrocnemius, and deep) highlight differences in T2* signal intensity provoked by reactive hyperemia. Consistent differences, particularly during ischemia and reactive hyperemia, are seen among the young control subjects (blue), age-matched control subjects (orange), the patient’s contralateral limb (gray), and the patient’s ischemic limb (red). Values (mean ± SD) for Grad (B) and SRi (C) are significantly lower in the ischemic limb compared with the patients’ contralateral limb, age-matched control subjects, and young healthy control subjects. ANOVA = analysis of variance; other abbreviations as in Figure 1.