Spinal cord stimulation (SCS) has been reported to impact peripheral blood flow when used to treat pain from a variety of conditions.1-4 Peripheral blood flow measurements can be obtained via laser Doppler flowmetry (LDF), photo-plethysmography (PPG), and transcutaneous oxygen pressure (TcPO2); each having their own technology-specific drawbacks.5,6 Laser speckle spectroscopy (LSS) is an alternative way to measure peripheral blood flow that may overcome the limitations of previous technologies by quantitatively measuring blood flow through the full volume of a digit, and producing a blood flow waveform in real time. Real-time changes in blood flow in response to SCS could be useful in determining the impact of stimulation beyond pain relief by modifying the underlying disease state or improving circulation where blood flow in an affected limb is impaired. The aim of this study is to gain experience with perfusion measurements in SCS patients, and to characterize and quantify blood flow with stimulation on versus off.