Figure 4.

Grading Scale for quadriceps muscles by magnetic resonance images (MRI). Muscle MRIs were used to establish a grading scale for the quadriceps muscles based on approximate percentage of increased image intensity indicating degree of fibrosis replacing normal muscle. There was an overall correlation between fibrosis and distance walked on the 6MWT with Patients 03 and 04 demonstrating the least benefit from gene transfer. RF, rectus femoris; VL/VI, vastus lateralis/vastus intermedius; VM, vastus medialis.