Background Decreased peripheral blood perfusion is a typical clinical aspect of systemic sclerosis (SSc) (1,2). Laser speckle contrast analysis (LASCA) is a new technique to assess and quantify blood perfusion (BP) in different skin areas of the body (3).
Objectives The aim of the study was to assess by LASCA the BP in different areas of the hand and face, in SSc patients and healthy subjects.
Methods Twenty-one SSc patients (mean disease duration 7±6 years) and twenty-five healthy subjects (matched for sex and age with SSc patients) were enrolled, after informed consent. BP was analysed by LASCA technique at level of face and dorsal and palmar regions of the hands in both SSc patients and healthy subjects. Different regions of interest (ROIs) were created at fingertips, periungual areas, palm and dorsum of both hands, as well as at the level of the face (forehead, tip of nose, zygomas and perioral region). The average BP was scored as perfusion units (PU). Concerning LASCA technique, when an object is illuminated by laser light, the backscattered light will form a random interference pattern consisting of dark and bright areas (speckle pattern). If the illuminated object is static, the speckle pattern is stationary; when there is movement in the object, such as red blood cells in a tissue, the speckle pattern will change over time. The machine records these changes in the speckle pattern. Non-parametric tests were used to carry out the statistical analysis.
Results SSc patients showed a statistically significant lower median BP than healthy subjects at the level of fingertips (112 and 164 PU, respectively, p=0.02) and periungual areas (93 and 147 PU, respectively, p=0.003). A statistically significant positive correlation was observed between BP of the fingertips and BP of the periungual areas in both SSc patients (r=0.94, p<0.0001) and healthy subjects (r=0.87, p<0.0001). Furthermore, in both SSc patients and healthy subjects, a statistically significant correlation was observed between palm of hand and fingertip areas (r=0.76 p<0.0001, and r=0.70 p<0.0001, respectively), dorsum of hand and periungual areas (r=0.69 p=0.0005, and r=0.36 p=0.05, respectively), dorsum and palm of hand (r=0.67 p=0.001, and r=0.39 p=0.05, respectively). The median gradient of BP between palm of hand and fingertips was found lower in SSc patients than in healthy subjects (3 and 46 PU, respectively, p=0.0002), as well as the gradient between dorsum of hand and periungual areas (25 and 69 PU, respectively, p=0.0009). No statistically significant difference in BP values was observed at the level of dorsum and palm of hands, as well as of different ROIs of the face or whole face, between SSc and healthy subjects.
Conclusions This study shows that LASCA technique detect significant differences of BP at the level of fingertips and periungual areas in SSc patients versus healthy subjects. However, at the level of palm/dorsum of hands and face, no significant BP difference have been detected between SSc patients and healthy subjects.
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Disclosure of Interest: None Declared