Fig. 3.

MSOT imaging and correlation with disease burden and clinical standard assessment. a) Exemplary image sections of the right biceps of four SMA patients with their matched HVs are shown to illustrate differences between MSOT SWL 800 nm signal intensities. In HVs a homogeneous signal band was detected just beneath the muscle fascia independent of gender and age. In SMA III patients one saw beginning changes towards inhomogeneous signal intensities in the muscles. In SMA I patients signal intensities were patchy transformed or even (finally) erased. Scale bar indicates 1 cm. b) Correlations between clinical standard assessments (HFMSE, score 0–66; RULM, score 0–37) and MSOT SWL 800 nm (signal intensity in a.u.) are shown for n = 19 participants. Spearman correlation coefficient (r_s), a p value ≤ 0.05 was regarded as statistically significant. c) A receiver operator characteristics (ROC) analysis was calculated for pooled MSOT SWL 800 nm (signal intensity in a.u.) between HVs and SMA-patients (n = 10 HV and n = 10 SMA patients).