Diffuse Cutaneous Scleroderma (DSSc) SFDI Study

Scleroderma (SSc) is an autoimmune disease characterized by fibrosis (or collagen deposition) of the skin and internal organs. The extent of skin fibrosis is an important predictor of internal organ complications and increased mortality. Currently a very imprecise, subjective method that varies amongst different doctors for the same patient is used to quantify skin fibrosis in patients, by "pinching" their skin and assessing how thick it is; this is the method used to determine the modified Rodnan skin score (mRSS).

A previous plot study was conducted by the investigators to determine if spatial frequency domain imaging (SFDI), a method of light scattering, could be used to measure the collagen content in the skin of SSc patients. This non-painful, noninvasive method takes very little time and the investigators hypothesized that it would be more accurate than the "pinching" method. For that pilot study, patients with various stages of the disease were selected, and SFDI was used to image 6 areas. A forearm skin biopsy was taken for subsequent histopathology analyses of collagen content. The clinical mRSS was assessed at the time of SFDI measurement. Optical property imaging data was analyzed and statistically correlated and analyzed with immunohistochemistry (a method of identifying proteins) of the skin. Preliminary results demonstrated a strong correlation between mRSS and SFDI. Some of the imaging parameters of the SFDI were modified based on the initial results. Initial results demonstrated that the device can detect increases in skin thickness observed in SSc skin.