Project Grant R44EY032847

IMAGING OF EPISCLERAL VENOUS BLOOD FLOW FOR ASSESSMENT OF MICRO-INVASIVE GLAUCOMA SURGERY - ABSTRACT GLAUCOMA, CAUSED BY RETINAL GANGLION CELL DEATH OR LOSS ASSOCIATED WITH ELEVATED INTRA-OCULAR PRESSURE (IOP), IS ONE OF THE LEADING CAUSES OF IRREVERSIBLE BLINDNESS GLOBALLY. CURRENT TREATMENT STRATEGIES SEEK TO REDUCE IOP BUT ARE LIMITED BY POOR ADHERENCE AND POTENTIALLY BLINDING SURGICAL COMPLICATIONS. MICROINVASIVE GLAUCOMA SURGERY (MIGS) OFFERS A PROMISING SOLUTION TO REDUCE IOP, HOWEVER RESULTS HAVE BEEN INCONSISTENT IN PART BECAUSE SURGEONS LACK THE MEANS TO ASSESS THE IMPROVEMENT OF AQUEOUS HUMOR OUTFLOW INTRAOPERATIVELY, THUS LIMITING THE SUCCESS OF MIGS. OUR PROJECT PROPOSES TO DEVELOP A SOLUTION BY LEVERAGING LASER SPECKLE CONTRAST IMAGING (LSCI) TO CHARACTERIZE EPISCLERAL VENOUS BLOOD FLOW (EVBF) INTRAOPERATIVELY AND ASSIST OPHTHALMIC SURGEONS PERFORMING MIGS IN REAL-TIME TO GUIDE THEIR SURGICAL APPROACH. DURING PHASE I, WE DEVELOPED A PROTOTYPE HARDWARE-SOFTWARE PLATFORM (CALLED VASOVUE) THAT COULD SIMULTANEOUSLY PERFORM LSCI, HIGH CONTRAST REFLECTANCE IMAGING (HCRI), AND FLUORESCENCE IMAGING (FLI) AND DEMONSTRATED IN ANIMAL MODELS THAT IOP CHANGES BROUGHT ABOUT CHANGES IN EVBF AND THAT EVBF WAS SIGNIFICANTLY DIFFERENT FOLLOWING GONIOTOMY. DURING PHASE II, WE WILL CONDUCT A CLINICAL STUDY TO CHARACTERIZE LSCI-DERIVED EVBF CHANGES ASSOCIATED WITH GLAUCOMA STATUS AND MIGS (AIM 1), AND IN A SEPARATE CLINICAL STUDY, DEMONSTRATE THE FEASIBILITY OF MEASURING EVBF INTRAOPERATIVELY DURING MIGS AND EVALUATE ITS USEFULNESS IN PREDICTING LONG-TERM IOP REDUCTION (AIM 2). IF SUCCESSFUL, WE EXPECT TO LAY A STRONG FOUNDATION FOR MULTI-CENTER CLINICAL EVALUATION OF OUR VASOVUE TECHNOLOGY TO DEVELOP ROBUST GUIDELINES FOR ITS INTEGRATION INTO THE WORKFLOW OF MIGS, AND UNDERTAKE DEVELOPMENT AND TESTING ACTIVITIES TO SEEK REGULATORY CLEARANCE FOR THE VASOVUE SYSTEM.