title: Miniperc and retrograde intrarenal surgery: when and how?
abstract: BACKGROUND
  Extracorporeal shock wave lithotripsy (ESWL) and percutaneous nephrolithotomy (PCNL) are consolidated procedures for the treatment of kidney stones; however, their primary weak points are the lower efficacy of ESWL, especially for lower calyx stones, and the morbidity of PCNL resulting from the creation and dilation of the percutaneous trajectory. The increasing miniaturization of percutaneous surgery instrumentation and the development of retrograde intrarenal surgery (RIRS) are recent innovations.
  
  
  METHODS
  A structured nonsystematic review was conducted through a literature search of articles published between 1997 and 2013, using the terms kidney stones, miniperc, mini-PCNL, RIRS and flexible ureteroscopy in the PubMed, Google Scholar and Scopus databases.
  RIRS requires greater surgical time, several procedures for voluminous stones and higher hospital costs, due in part to the relative fragility of the instruments. On the other hand, miniperc requires a longer hospital stay, an increased need for postoperative analgesia and a greater reduction in hemoglobin levels, although these do not translate into an increased rate of transfusions.
  
  
  CONCLUSIONS
  The current treatment of kidney stones uses minimally invasive procedures such as miniperc and RIRS. The 2 procedures are equivalent in terms of efficacy (stone clearance) and are associated with minimal complications. Comparative prospective studies are necessary to determine the position of each of these techniques in the treatment of kidney stones. In our experience, the 2 techniques are complementary and should be part of the current urological therapeutic arsenal.
authors: Servicio de Urología, Hospital Universitario de Getafe, Universidad Europea de Madrid, Madrid, España.
authors: F
authors: F
authors: Ramón de Fata
authors: Urologische Klinik und Poliklinik, Klinikum rechts der Isar, Technische Universität München, Múnich, Alemania.
authors: K
authors: K
authors: Hauner
authors: Servicio de Urología, Hospital Universitario de Getafe, Universidad Europea de Madrid, Madrid, España.
authors: G
authors: G
authors: Andrés
authors: Servicio de Urología, Hospital Universitario de Getafe, Universidad Europea de Madrid, Madrid, España. Electronic address: jangulo@futurnet.es.
authors: J C
authors: JC
authors: Angulo
authors: Urologische Klinik und Poliklinik, Klinikum rechts der Isar, Technische Universität München, Múnich, Alemania.
authors: M
authors: M
authors: Straub
mesh_terms: D006801:Humans; D007669:Kidney Calculi / Q000601:surgery*; D019060:Minimally Invasive Surgical Procedures / Q000295:instrumentation / Q000379:methods; D009403:Nephrostomy, Percutaneous / Q000295:instrumentation / Q000379:methods*
keywords: Cirugía Retrógrada intrarrenal; Indicaciones; Indications; Kidney stone; Litiasis Renal; Mini-Nefrolitotomía Percutánea; Minipercutaneous nephrolithotomy; Retrograde intrarenal surgery; Technique; Técnica