title: Ureteroscopy-assisted Percutaneous Kidney Access Made Easy: First Clinical Experience with a Novel Navigation System Using Electromagnetic Guidance (IDEAL Stage 1).
abstract: Puncture of the renal collecting system represents a challenging step in percutaneous nephrolithotomy (PCNL). Limitations related to the use of standard fluoroscopic-based and ultrasound-based maneuvers have been recognized.
  
  
  
  To describe the technique and early clinical outcomes of a novel navigation system for percutaneous kidney access.
  
  
  
  This was a proof-of-concept study (IDEAL phase 1) conducted at a single academic center. Ten PCNL procedures were performed for patients with kidney stones.
  
  
  
  Flexible ureterorenoscopy was performed to determine the optimal renal calyx for access. An electromagnetic sensor was inserted through the working channel. Then the selected calyx was punctured with a needle with a sensor on the tip guided by real-time three-dimensional images observed on the monitor.
  
  
  
  The primary endpoints were the accuracy and clinical applicability of the system in clinical use. Secondary endpoints were the time to successful puncture, the number of attempts for successful puncture, and complications.
  
  
  
  Ten patients were enrolled in the study. The median age was 47.1 yr (30-63), median body mass index was 22.85kg/m2(19-28.3), and median stone size was 2.13cm (1.5-2.5cm). All stones were in the renal pelvis. The Guy's stone score was 1 in nine cases and 2 in one case. All 10 punctures of the collecting system were successfully completed at the first attempt without X-ray exposure. The median time to successful puncture starting from insertion of the needle was 20 s (range 15-35). No complications occurred.
  
  
  
  We describe the first clinical application of a novel navigation system using real-time electromagnetic sensors for percutaneous kidney access. This new technology overcomes the intrinsic limitations of traditional methods of kidney access, allowing safe, precise, fast, and effective puncture of the renal collecting system.
  
  
  
  We describe a new technology allowing safe and easy puncture of the kidney without radiation exposure. This could significantly facilitate one of the most challenging steps in percutaneous removal of kidney stones.
authors.affiliation: Department of CUF Urology, Surgical Sciences Research Domain, Life and Health Sciences Research Institute, School of Medicine, University of Minho, Braga, Portugal. Electronic address: estevaolima@med.uminho.pt.
authors.forename: Estevao
authors.initials: E
authors.lastname: Lima
authors.affiliation: Department of CUF Urology, Surgical Sciences Research Domain, Life and Health Sciences Research Institute, School of Medicine, University of Minho, Braga, Portugal; DIGARC, Polytechnic Institute of Cávado and Ave, Barcelos, Portugal.
authors.forename: Pedro L
authors.initials: PL
authors.lastname: Rodrigues
authors.affiliation: Department of CUF Urology, Surgical Sciences Research Domain, Life and Health Sciences Research Institute, School of Medicine, University of Minho, Braga, Portugal.
authors.forename: Paulo
authors.initials: P
authors.lastname: Mota
authors.affiliation: Department of CUF Urology, Surgical Sciences Research Domain, Life and Health Sciences Research Institute, School of Medicine, University of Minho, Braga, Portugal.
authors.forename: Nuno
authors.initials: N
authors.lastname: Carvalho
authors.affiliation: Department of CUF Urology, Surgical Sciences Research Domain, Life and Health Sciences Research Institute, School of Medicine, University of Minho, Braga, Portugal.
authors.forename: Emanuel
authors.initials: E
authors.lastname: Dias
authors.affiliation: Department of CUF Urology, Surgical Sciences Research Domain, Life and Health Sciences Research Institute, School of Medicine, University of Minho, Braga, Portugal.
authors.forename: Jorge
authors.initials: J
authors.lastname: Correia-Pinto
authors.affiliation: Department of CUF Urology, Surgical Sciences Research Domain, Life and Health Sciences Research Institute, School of Medicine, University of Minho, Braga, Portugal.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Autorino
authors.affiliation: Department of CUF Urology, Surgical Sciences Research Domain, Life and Health Sciences Research Institute, School of Medicine, University of Minho, Braga, Portugal; DIGARC, Polytechnic Institute of Cávado and Ave, Barcelos, Portugal.
authors.forename: João L
authors.initials: JL
authors.lastname: Vilaça
mesh_terms: D000328:Adult; D055590:Electromagnetic Phenomena; D006801:Humans; D015907:Hysteroscopy / Q000009:adverse effects; D021621:Imaging, Three-Dimensional; D007668:Kidney / Q000000981:diagnostic imaging / Q000601:surgery*; D007669:Kidney Calculi / Q000000981:diagnostic imaging / Q000601:surgery*; D008875:Middle Aged; D000074642:Nephrolithotomy, Percutaneous / Q000009:adverse effects / Q000379:methods*; D061646:Operative Time; D011183:Postoperative Complications / Q000209:etiology; D000075082:Proof of Concept Study; D011446:Prospective Studies; D011677:Punctures; D025321:Surgery, Computer-Assisted / Q000009:adverse effects / Q000379:methods*; D013997:Time Factors; D016896:Treatment Outcome
keywords: Combined access; Image-guided surgery; Kidney access; Kidney puncture; Percutaneous nephrolithotomy; Real time; Surgical navigation