Translational optical coherence elastography for assessment of systemic sclerosis.

Systemic sclerosis (SSc-scleroderma) is an autoimmune disorder with high mortality rate that results in excessive accumulation of collagen in the skin and internal organs. Currently, the modified Rodnan Skin Score (mRSS) is the gold standard for evaluating the dermal thickening due to SSc. However, mRSS has noticeable inter- and intra-observer variabilities as quantified by the interclass correlation coefficient (ICC: 0.6-0.75). In this work, optical coherence elastography (OCE) combined with structural optical coherence tomography (OCT) image analysis was used to assess skin thickness in 12 SSc patients and healthy volunteers. Inter- (ICC: 0.62-0.99) and intra-observer (ICC > 0.90) assessment of OCT/OCE showed excellent reliability. Clinical assessments, including histologically assessed dermal thickness (DT), mRSS, and site-specific mRSS (SMRSS) were also performed for further validation. The OCE and OCT results from the forearm demonstrated the highest correlation (OCE: 0.78, OCT: 0.65) with SMRSS. Importantly, OCE and OCT had stronger correlations with the histological DT (OCT: r = .78 and OCE: r = .74) than SMRSS (r = .57), indicating the OCT/OCE could outperform semi-quantitative clinical assessments such as SMRSS. Overall, these results demonstrate that OCT/OCE could be useful for rapid, noninvasive and objective assessments of SSc onset and monitoring skin disease progression and treatment response.

Predictors of Hand Contracture in Early Systemic Sclerosis and the Effect on Function: A Prospective Study of the GENISOS Cohort.

OBJECTIVE: To identify baseline features that predict progression of hand contractures and to assess the effect of contractures on functional status in the prospective GENISOS cohort. METHODS: Rate of decline in hand extension, as an indicator of hand contracture, was the primary outcome. We assessed longitudinal hand extension measurements, modified Health Assessment Questionnaire (MHAQ) score, Medical Outcomes Study Short Form-36 (SF-36) physical function score, and demographic, clinical, and serological variables. Subjects with ≥ 2 hand measurements at least 6 months apart were included. RESULTS: A total of 1087 hand measurements for 219 patients were available over an average of 8.1 ± 4.8 years. Hand extension decreased on average by 0.11 cm/year. Antitopoisomerase I antibody (ATA) positivity and higher modified Rodnan Skin Score (mRSS) were predictive of faster decline in hand extension (p = 0.009 and p = 0.046, respectively). In a subgroup analysis of 62 patients with ≤ 2 years from SSc onset, ATA and diffuse disease type were associated with faster decline in hand extension; anticentromere positivity was associated with slower rate of decline. Although the rate of decline in patients with disease duration ≤ 2 years was numerically higher, the difference was not statistically significant. Hand extension continued to decline in a linear fashion over time and was inversely related to overall functional status. CONCLUSION: ATA was predictive of contracture development in both early disease (≤ 2 yrs) and in the overall cohort. Hand extension declined linearly over time and was inversely associated with MHAQ and SF-36 scores. ATA positivity and higher baseline mRSS were predictive of faster decline in hand extension.