Table 1.

Noninvasive vascular methods

Noninvasive vascular method	Vascular data provided	Principle strength	Main weakness
Nailfold capillaroscopy	Morphological	Standardized protocol	Trained operator
Sublingual capillaroscopy	Functional	Automated	Availability
Laser speckle contrast imaging (LSCI)	Functional	Noncontact	Inadequate in low perfusion
Laser speckle contrast analysis (LASCA)	Functional	Intra-operator variability	Spatial resolution
Infrared thermography	Functional	Specific for skin circulation	Detailed protocol
Calcinosis assessment • Ultrasound (US) • CT • MRI • PET	Morphological	• US: cost • CT/MRI: preoperative anatomic information • PET: widespread evaluation	• US: trained operator • CT: radiation • MRI: misses small foci • PET: cost
Optical coherence tomography angiography (OCT-A)	Morphological	Quantitative in two layers of skin	Validation in SSc
Peripheral arterial tonometry (PAT)	Functional	Automated	Fingertip occlusion
Digital thermal monitoring (DTM)	Functional	Automated	Requires adequate baseline temperature
Flow mediated dilatation (FMD)	Functional	Standardized protocol	Trained operator
Quantitative sudomotor axon reflex test (QSART)	Functional	Captures neurologic skin symptoms	Trained operator