Background

Facioscapulohumeral muscular dystrophy (FSHD), one of the most prevalent muscular dystrophies in the adulthood, is characterized by progressive fatty replacement and degeneration involving single muscles in an asynchronous and largely variable manner. Multi-spectral optoacoustic tomography (MSOT) is an innovative imaging technique able to non-invasively characterize the molecular composition of the muscle tissue using pulsed lasers in the near-infrared spectrum. With this pilot study we 1) explored the performance of MSOT imaging in characterizing muscles from FSHD patients 2) compared them with healthy volunteers’ muscles 3) evaluated the relationship between MSOT parameters and clinical and MRI features of the patients.

Methods

Adult subjects with a molecular diagnosis of FSHD and healthy individuals were recruited. Participants underwent an MSOT scan of predefined upper and lower limb muscles, following a standardized protocol. FSHD patients performed a muscle MRI scan close to the MSOT examination, alongside with clinical characterization. The optoacoustic absorption spectrum (peaks at different wavelengths in arbitrary units) of FSHD and controls muscles were compared globally and at single muscle level. The spectra were also correlated with MRI findings and clinical scores.

Results

A total of 15 patients and 9 healthy subjects were enrolled. The muscle-specific optoacoustic absorption spectrum showed significant differences between FSHD patients and controls. Further data analysis is still on-going and will be presented at the conference.

Conclusions

This study highlights the potential of MSOT imaging as a promising non-invasive tool to be exploited for the identification of new biomarkers of disease activity and progression in FSHD.