Endoscopic laser imaging of tissue perfusion: New instrumentation and technique

Background and Objectives: New instrumentation, based on a previously established laser speckle perfusion imaging (LSI) technique is evaluated for its ability to capture and generate blood flow images during endoscopic surgery. Study Design/Materials and Methods: Investigations are detailed in an in-vitro blood flow model simulating physiological properties of vascularized tissue, and in-vivo in rabbit joint capsule tissue. Results: In-vitro measurements showed a linear response of the instrument to blood flow in the range of 0-800 mul/minute, where data points were significantly correlated with an r(2) value of 0.96. In-vivo measurements showed a 58.7% decrease to the medial collateral ligament during occlusion of the femoral artery. Conclusions: Blood flow images demonstrate that the endoscopic LSI technique is capable of measuring relative tissue blood flow changes at high resolutions and rapid response times and incorporates well with endoscopic surgeries. (C) 2003 Wiley-Liss, Inc.