title: Feasibility of quantitative diffuse reflectance spectroscopy for targeted measurement of renal ischemia during laparoscopic partial nephrectomy.
abstract: Reduction of warm ischemia time during partial nephrectomy (PN) is critical to minimizing ischemic damage and improving postoperative kidney function, while maintaining tumor resection efficacy. Recently, methods for localizing the effects of warm ischemia to the region of the tumor via selective clamping of higher-order segmental artery branches have been shown to have superior outcomes compared with clamping the main renal artery. However, artery identification can prolong operative time and increase the blood loss and reduce the positive effects of selective ischemia. Quantitative diffuse reflectance spectroscopy (DRS) can provide a convenient, real-time means to aid in artery identification during laparoscopic PN. The feasibility of quantitative DRS for real-time longitudinal measurement of tissue perfusion and vascular oxygenation in laparoscopic nephrectomy was investigated in vivo in six Yorkshire swine kidneys (n=three animals ). DRS allowed for rapid identification of ischemic areas after selective vessel occlusion. In addition, the rates of ischemia induction and recovery were compared for main renal artery versus tertiary segmental artery occlusion, and it was found that the tertiary segmental artery occlusion trends toward faster recovery after ischemia, which suggests a potential benefit of selective ischemia. Quantitative DRS could provide a convenient and fast tool for artery identification and evaluation of the depth, spatial extent, and duration of selective tissue ischemia in laparoscopic PN.
authors.affiliation: Tulane University School of Medicine, Department of Urology, New Orleans, Louisiana 70112, United States.
authors.forename: Utsav O
authors.initials: UO
authors.lastname: Goel
authors.affiliation: Tulane University School of Medicine, Department of Urology, New Orleans, Louisiana 70112, United States.
authors.forename: Michael M
authors.initials: MM
authors.lastname: Maddox
authors.affiliation: Tulane University, Department of Biomedical Engineering, New Orleans, Louisiana 70118, United States.
authors.forename: Katherine N
authors.initials: KN
authors.lastname: Elfer
authors.affiliation: Tulane University School of Medicine, Department of Urology, New Orleans, Louisiana 70112, United States.
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Dorsey
authors.affiliation: Tulane University, Department of Biomedical Engineering, New Orleans, Louisiana 70118, United States.
authors.forename: Mei
authors.initials: M
authors.lastname: Wang
authors.affiliation: Tulane University School of Medicine, Department of Urology, New Orleans, Louisiana 70112, United States.
authors.forename: Ian Ross
authors.initials: IR
authors.lastname: McCaslin
authors.affiliation: Tulane University, Department of Biomedical Engineering, New Orleans, Louisiana 70118, United States.
authors.forename: J Quincy
authors.initials: JQ
authors.lastname: Brown
authors.affiliation: Tulane University School of Medicine, Department of Urology, New Orleans, Louisiana 70112, United States.
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Lee
mesh_terms: D000818:Animals; D005240:Feasibility Studies; D006454:Hemoglobins / Q000032:analysis; D007511:Ischemia / Q000097:blood / Q000145:classification* / Q000503:physiopathology; D007668:Kidney / Q000098:blood supply / Q000601:surgery; D007674:Kidney Diseases / Q000601:surgery; D010535:Laparoscopy / Q000009:adverse effects* / Q000379:methods*; D009392:Nephrectomy / Q000009:adverse effects / Q000379:methods*; D061848:Optical Imaging / Q000379:methods*; D012077:Renal Artery / Q000601:surgery; D013057:Spectrum Analysis / Q000379:methods*; D013552:Swine
chemical_list: D006454:Hemoglobins