FIGURE 3.
Average muscle gray scale levels by age in healthy boys and boys with DMD. Average muscle GSL is higher in DMD than in controls (P < 0.001) even in children as young as 2 years, and there was a trend to increase with age in boys with DMD (r = 0.4, P = 0.1) but not in healthy controls (r = −0.2, P = 0.5).