title: The Advantage of a Ureteroscopic Navigation System with Magnetic Tracking in Comparison with Simulated Fluoroscopy in a Phantom Study.
abstract: OBJECTIVE
  To assess whether our ureteroscopic real-time navigation system has the possibility to reduce radiation exposure and improve performance of ureteroscopic maneuvers in surgeons of various ages and experience levels.
  
  
  METHODS
  Our novel ureteroscopic navigation system used a magnetic tracking device to detect the position of the ureteroscope and display it on a three-dimensional image. We recruited 31 urologists from five institutions to perform two tasks. Task 1 consisted of finding three internal markings on the phantom calices. Task 2 consisted of identifying all calices by ureteroscopy. In both tasks, participants performed with simulated fluoroscopy first, followed by our navigation system. Accuracy rates (AR) for identification, required time (T) for completing the task, migration length (ML), and time exposed to simulated fluoroscopy were recorded.
  
  
  RESULTS
  The AR, T, and ML for both tasks were significantly better with the navigation system than without it (Task 1 with simulated fluoroscopy vs with navigation: AR 87.1 % vs 98.9%, P=0.003; T 355 s vs 191 s, P<0.0001; ML 4627 mm vs 2701 mm, P<0.0001. Task 2: AR 88.2% vs 96.7%, P=0.011; T 394 s vs 333 s, P=0.027; ML 5966 mm vs 5299 mm, P=0.0006). In both tasks, the participants used the simulated fluoroscopy about 20% of the total task time.
  
  
  CONCLUSIONS
  Our navigation system, while still under development, could help surgeons of all levels to achieve better performances for ureteroscopic maneuvers compared with using fluoroscopic guidance. It also has the potential to reduce radiation exposure during fluoroscopy.
authors: 1 Department of Urology and Andrology, Kansai Medical University , Osaka, Japan .
authors: Kenji
authors: K
authors: Yoshida
authors: 2 Department of Urology, Graduate School of Medical Sciences, Kyushu University , Fukuoka, Japan .
authors: Akira
authors: A
authors: Yokomizo
authors: 1 Department of Urology and Andrology, Kansai Medical University , Osaka, Japan .
authors: Tadashi
authors: T
authors: Matsuda
authors: 3 Department of Urology, Nippon Medical School , Tokyo, Japan .
authors: Tsutomu
authors: T
authors: Hamasaki
authors: 3 Department of Urology, Nippon Medical School , Tokyo, Japan .
authors: Yukihiro
authors: Y
authors: Kondo
authors: 4 Department of Urology, Institute of HBS, The University of Tokushima Graduate School , Tokushima, Japan .
authors: Kunihisa
authors: K
authors: Yamaguchi
authors: 4 Department of Urology, Institute of HBS, The University of Tokushima Graduate School , Tokushima, Japan .
authors: Hiro-Omi
authors: HO
authors: Kanayama
authors: 5 Department of Urology of Juntendo University , Tokyo, Japan .
authors: Yoshiaki
authors: Y
authors: Wakumoto
authors: 5 Department of Urology of Juntendo University , Tokyo, Japan .
authors: Shigeo
authors: S
authors: Horie
authors: 2 Department of Urology, Graduate School of Medical Sciences, Kyushu University , Fukuoka, Japan .
authors: Seiji
authors: S
authors: Naito
mesh_terms: D003198:Computer Simulation; D005260:Female; D005471:Fluoroscopy / Q000295:instrumentation* / Q000379:methods*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging; D008280:Magnetics / Q000295:instrumentation; D008297:Male; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D025321:Surgery, Computer-Assisted; D020709:Ureteroscopes; D018666:Ureteroscopy / Q000379:methods*; D014572:Urology / Q000379:methods