title: Ureteroscopy assisted retrograde nephrostomy: a new technique for percutaneous nephrolithotomy (PCNL).
abstract: Study Type - Therapy (case series). Level of Evidence 4. What's known on the subject? and What does the study add? Retrograde nephrostomy was first developed by Lawson et al. in 1983, and Hunter et al. reported 30 cases of retrograde nephrostomy in 1987. This procedure uses less radiation exposure and has a shorter duration compared with the previous percutaneous nephrostomy techniques. Retrograde nephrostomy using Lawson's procedure was reported in the late 1980s by several authors. But since then, few studies have been reported about this procedure due to the development of ultrasonography assisted percutaneous nephrostomy. With the arrival and development of the flexible ureteroscope (URS) both observation and manipulation in the renal pelvis are now easily achieved. The present procedure provides less radiation exposure, less bleeding, and a shorter procedure than previous percutaneous nephrostomy techniques. Using this procedure, after the needle has exited through the skin, no further steps are required in preparation for dilatation. In the present study, we continuously visualised from puncture to inserting the nephron-access sheath with the URS.
  
  
  OBJECTIVE
  • To describe a technique for ureteroscopy assisted retrograde nephrostomy.
  
  
  METHODS
  • Under general and epidural anaesthesia, the patient is placed in a modified-Valdivia position. Flexible ureteroscopy is carried out, and a Lawson retrograde nephrostomy puncture wire is placed in the ureteroscope (URS). • After the needle has exited through the skin, no further steps are required in preparation for dilatation.
  
  
  RESULTS
  • After informed consent was obtained, two patients (a 43-year-old man with left renal stones and a 57-year-old woman with right renal stones) underwent this procedure. • The URS was positioned in the middle posterior calyx and punctured toward the skin.
  
  
  CONCLUSIONS
  • This procedure involves less radiation exposure and shorter surgery than the previous percutaneous nephrostomy technique. • Our technique represents another new option for percutaneous nephrolithotomy in patients with a non-dilated intrarenal collecting system.
authors.affiliation: Departments of Urology, Ohguchi Higashi General Hospital, Kanagawa, Japan. takashi_tk2001@yahoo.co.jp
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawahara
authors.forename: Hiroki
authors.initials: H
authors.lastname: Ito
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Terao
authors.forename: Minoru
authors.initials: M
authors.lastname: Yoshida
authors.forename: Takehiko
authors.initials: T
authors.lastname: Ogawa
authors.forename: Hiroji
authors.initials: H
authors.lastname: Uemura
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Kubota
authors.forename: Junichi
authors.initials: J
authors.lastname: Matsuzaki
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000379:methods*; D018666:Ureteroscopy / Q000379:methods*