Laser speckle contrast analysis: a new method to evaluate peripheral blood perfusion in systemic sclerosis patients

Objective The aim of this pilot study was to assess peripheral blood perfusion (PBP) by a new technique, the laser speckle contrast analysis (LASCA), in systemic sclerosis (SSc) patients showing different patterns of nailfold microangiopathy. Correlations between LASCA and single laser Doppler flowmetry (LDF) analysis were also checked. Methods Sixty-one SSc patients and 61 healthy subjects were enrolled. PBP was evaluated using LASCA and LDF. Scleroderma patterns and microangiopathy evolution score (MES) were assessed by nailfold videocapillaroscopy (NVC). Results As detected by LASCA and LDF, PBP was lower in SSc patients than in healthy subjects (p<0.0001), showing SSc patients with the 'Early', 'Active' or 'Late' NVC pattern a progressively lower PBP (p=0.04 and p=0.002, respectively). There was a negative correlation between PBP and MES values (p=0.006 and p=0.002 for LASCA and LDF, respectively). A positive correlation was detected between LASCA and LDF values, in all subjects (p<0.0001). However, LASCA evaluates larger skin areas, is significantly less time consuming, is more accepted by patients and shows lower intra-operator variability than LDF. Conclusions LASCA detected lower PBP in SSc patients than in healthy subjects, and for the first time, LASCA perfusion values were found correlated with progression of NVC patterns of microangiopathy.