title: Percutaneous nephrolithotomy for isolated calyceal stones: How important is the stone location?
abstract: OBJECTIVE
  To evaluate the effect of percutaneous access site on the success and complication rates of isolated calyceal stones.
  
  
  METHODS
  We retrospectively evaluated 2700 patients who underwent percutaneous nephrolithotomy (PNL) in our clinic between October 2002 and August 2014. We selected only the patients with isolated lower, middle or upper calyceal stones and we grouped the patients according to the location of their stones. Successful operation was defined as complete stone clearence or retention of stone fragments smaller than 4 mm which do not lead to infection, obstruction or pain requiring treatment. Intraoperative and postoperative complications were also recorded.
  
  
  RESULTS
  Totally 360 patients underwent PNL for their isolated upper, middle and lower calyceal stones. Access sites for those patients were selected based on stone location. The stones were localized in the lower (n=304), middle (n=14), and upper (n=42) calices. There was no statistically significant difference between the groups with respect to operation and scopy times. Hemoglobin drop was seen more frequently in the upper calyceal access group, without any significant intergroup difference. Thoracic complications including hemothorax, pneumothorax and pleural effusion were more common in the upper calyceal access group (11.9%; p<0.001). Complete stone clerance was accomplished in 81.9%, 92.9% and 78.6% of the patients with lower, middle and upper calyceal stones respectively without any significant intergroup difference (p=0.537).
  
  
  CONCLUSIONS
  PNL is an effective and safe treatment modality for isolated calyceal kidney stones and upper calyceal access causes thoracic complications more than other access sites.
authors.affiliation: Clinic of Urology, Haseki Training and Research Hospital, Istanbul, Turkey.
authors.forename: Faruk
authors.initials: F
authors.lastname: Özgör
authors.affiliation: Clinic of Urology, Haseki Training and Research Hospital, Istanbul, Turkey.
authors.forename: Onur
authors.initials: O
authors.lastname: Küçüktopcu
authors.affiliation: Clinic of Urology, Haseki Training and Research Hospital, Istanbul, Turkey.
authors.forename: Abdulmuttalip
authors.initials: A
authors.lastname: Şimşek
authors.affiliation: Clinic of Urology, Haseki Training and Research Hospital, Istanbul, Turkey.
authors.forename: Ömer
authors.initials: Ö
authors.lastname: Sarılar
authors.affiliation: Clinic of Urology, Haseki Training and Research Hospital, Istanbul, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Binbay
authors.affiliation: Clinic of Urology, Haseki Training and Research Hospital, Istanbul, Turkey.
authors.forename: Gökhan
authors.initials: G
authors.lastname: Gürbüz
keywords: Isolated calyceal stones; kidney calculi; percutaneous nephrolitotomy