title: Real-time in vivo periprostatic nerve tracking using multiphoton microscopy in a rat survival surgery model: a promising pre-clinical study for enhanced nerve-sparing surgery.
abstract: OBJECTIVE
  To assess the ability of multiphoton microscopy (MPM) to visualise, differentiate and track periprostatic nerves in an in vivo rat model, mimicking real-time imaging in humans during RP and to investigate the tissue toxicity and reproducibility of in vivo MPM on prostatic glands in the rat after imaging and final histological correlation study.
  
  
  METHODS
  In vivo prostatic rat imaging was carried out using a custom-built bench-top MPM system generating real-time three-dimensional histological images, after performing survival surgery consisting of mini-laparotomies under xylazine/ketamine anaesthesia exteriorising the right prostatic lobe. The acquisition time and the depth of anaesthesia were adjusted for collecting multiple images in order to track the periprostatic nerves in real-time. The rats were then monitored for 15 days before undergoing a new set of imaging under similar settings. After humanely killing the rats, their prostates were submitted for routine histology and correlation studies.
  
  
  RESULTS
  In vivo MPM images distinguished periprostatic nerves within the capsule and the prostatic glands from fresh unprocessed prostatic tissue without the use of exogenous contrast agents or biopsy sample. Real-time nerve tracking outlining the prostate was feasible and acquisition was not disturbed by motion artefacts. No serious adverse event was reported during rat monitoring; no tissue damage due to laser was seen on the imaged lobe compared with the contralateral lobe (control) allowing comparison of their corresponding histology.
  
  
  CONCLUSIONS
  For the first time, we have shown that in vivo tracking of periprostatic nerves using MPM is feasible in a rat model. Development of a multiphoton endoscope for intraoperative use in humans is currently in progress and must be assessed.
authors.affiliation: Department of Urology, Weill Medical College of Cornell University, New York-Presbyterian Hospital, New York, NY, USA.|Department of Urology, Hôpital Archet 2, Centre Hospitalier Universitaire de Nice, University of Nice Sophia-Antipolis, Nice, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Durand
authors.affiliation: Department of Urology, Weill Medical College of Cornell University, New York-Presbyterian Hospital, New York, NY, USA.|Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York-Presbyterian Hospital, New York, NY, USA.
authors.forename: Manu
authors.initials: M
authors.lastname: Jain
authors.affiliation: Department of Biochemistry, Weill Medical College of Cornell University, New York-Presbyterian Hospital, New York, NY, USA.
authors.forename: Amit
authors.initials: A
authors.lastname: Aggarwal
authors.affiliation: Department of Urology, Weill Medical College of Cornell University, New York-Presbyterian Hospital, New York, NY, USA.|Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York-Presbyterian Hospital, New York, NY, USA.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Robinson
authors.affiliation: Department of Urology, Weill Medical College of Cornell University, New York-Presbyterian Hospital, New York, NY, USA.
authors.forename: Abhishek
authors.initials: A
authors.lastname: Srivastava
authors.affiliation: Department of Biochemistry, Weill Medical College of Cornell University, New York-Presbyterian Hospital, New York, NY, USA.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Smith
authors.affiliation: Surgical Intervention Trials Unit, University of Oxford, Oxford, UK.|Karolinska Institute, Stockholm, Sweden.
authors.forename: Prasanna
authors.initials: P
authors.lastname: Sooriakumaran
authors.affiliation: Department of Urology, Hôpital Archet 2, Centre Hospitalier Universitaire de Nice, University of Nice Sophia-Antipolis, Nice, France.
authors.forename: Joyce
authors.initials: J
authors.lastname: Loeffler
authors.affiliation: Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, USA.
authors.forename: Chris
authors.initials: C
authors.lastname: Pumill
authors.affiliation: Department of Urology, Hôpital Archet 2, Centre Hospitalier Universitaire de Nice, University of Nice Sophia-Antipolis, Nice, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Amiel
authors.affiliation: Department of Urology, Hôpital Archet 2, Centre Hospitalier Universitaire de Nice, University of Nice Sophia-Antipolis, Nice, France.
authors.forename: Daniel
authors.initials: D
authors.lastname: Chevallier
authors.affiliation: Department of Biochemistry, Weill Medical College of Cornell University, New York-Presbyterian Hospital, New York, NY, USA.
authors.forename: Sushmita
authors.initials: S
authors.lastname: Mukherjee
authors.affiliation: Department of Urology, Weill Medical College of Cornell University, New York-Presbyterian Hospital, New York, NY, USA.
authors.forename: Ashutosh K
authors.initials: AK
authors.lastname: Tewari
mesh_terms: D000818:Animals; D008297:Male; D036641:Microscopy, Fluorescence, Multiphoton / Q000379:methods*; D009417:Nerve Tissue / Q000737:chemistry; D059351:Organ Sparing Treatments; D011467:Prostate / Q000737:chemistry / Q000294:innervation / Q000601:surgery*; D011471:Prostatic Neoplasms / Q000473:pathology / Q000601:surgery; D051381:Rats; D017207:Rats, Sprague-Dawley; D025321:Surgery, Computer-Assisted / Q000379:methods*
keywords: imaging; in vivo; multiphoton microscopy; nerves; prostate cancer; virtual histology