Fig. 1.

Dixon-based PDFF estimation. Representative Dixon-based PDFF maps of thigh muscles of a patient with SMA A and a healthy control B. Subtotal intramuscular ROIs were drawn on these maps to quantify the fat fraction. An increased fat fraction goes along with a higher intramuscular signal. C Depicts the average intramuscular fat fractions in the biceps femoris and quadriceps muscles of SMA patients and healthy controls. Fat fractions were significantly higher in both muscles in patients with SMA at baseline (t0) and after 6 months (t1). No significant differences between the fat fractions in SMA patients were detected at baseline and after 6 months