Efficacy of Botulinum Toxin In Scleroderma-Associated Raynaud's Syndrome

This is a randomized, double-blinded, clinical trial assessing the therapeutic efficacy of Botulinum toxin A (Onabotulinumtoxin A) in treating scleroderma-associated Raynaud\'s syndrome. Each patient will undergo injection with a treatment dose of Botulinum toxin A in one randomly-selected hand, and the contralateral hand will be injected with sterile saline (placebo) to serve as a control. Study participants at the first study visit will complete study questionnaires, their hands will be assessed clinically for digital ulceration, and their hands will undergo non-invasive laser Doppler imaging to assess blood flow. After this initial assessment, the patients will undergo peri-arterial injection of Botulinum toxin A in one hand, and of sterile saline solution (placebo) in the other, in a randomized, blinded manner. Patient will report the severity of their Raynaud\'s symptoms weekly over the four month study period. At one month post-injection, the patient will complete study questionnaires, their hands will be assessed clinically for digital ulceration, and their hands will undergo non-invasive laser Doppler imaging. At four months post-injection, the patient will again complete study questionnaires, their hands will be assessed clinically for digital ulceration, and their hands will undergo non-invasive laser Doppler imaging. In addition, patient will be given the option of one week post-injection visit, at which point the same assessment will be performed. At the conclusion of the study, unblinding will occur.