Multimodal imaging evaluation of pre-systemic sclerosis patients presenting with Raynaud's Phenomenon from a...

To determine whether multimodal imaging tools can detect dermal and microvascular abnormalities in pre-systemic sclerosis (pre-SSc) patients compared with matched healthy controls (HC).

Non-selected pre-SSc patients (n = 20, fulfilling LeRoy's criteria) from the Ghent University (hospital) Raynaud's clinic and age-, sex-, and BMI-matched HC (n = 20) were evaluated. Dermal thickness (DT) was measured using high-frequency ultrasound (HFUS, 18 MHz) at 17 sites. Nailfold videocapillaroscopy (NVC, 200x magnification) was assessed using standardized consensus. Peripheral blood perfusion (PBP) was quantified using laser speckle contrast analysis (LASCA). Group differences were analysed using generalised linear mixed models with group, location and their interaction as fixed effects, accounting for matching and within-subject clustering.

HFUS showed an effect of group on mean DT (p = 0.011). Significant locations included the right and left fingers (0.80 ± 0.04 vs 0.68 ± 0.04 mm, p = 0.012; 0.81 ± 0.04 vs 0.67 ± 0.04 mm, p = 0.015) and left forearm (1.02 ± 0.05 vs 0.88 ± 0.05 mm, p = 0.035). LASCA demonstrated reduced (volar) fingertip PBP in pre-SSc (139 ± 12 vs 200 ± 12 perfusion units; mean difference = 61, 95% CI: 38-85; p < 0.001). NVC revealed lower capillary density (7.8 vs 9.8/mm, p < 0.001), increased microhaemorrhages (18%vs 7.4%, p = 0.032), and exclusivity of giant capillaries and scleroderma pattern.

Dermal, functional and structural microvascular abnormalities are detectable in pre-SSc in the absence of clinical skin thickening or overt organ involvement. Future multicentric longitudinal studies are required to confirm multimodal differentiative value.