title: Is tubeless percutaneous nephrolithotomy really less injurious than standard in the midterm?
abstract: OBJECTIVE
  To compare renal injury and vascular resistance between standard and tubeless percutaneous nephrolithotomy (PCNL) in patients who had undergone procedures for kidney stone by using colored Doppler ultrasonography (CDUS).
  
  
  METHODS
  All consecutive PCNLs were evaluated between 2009 and 2011. Patients in whom access was in the lower pole, and who regularly visited our outpatient clinic were enrolled in the study. Patients who underwent standard PCNL were included in group 1, and patients who underwent tubeless PCNL were included in group 2. All data were collected from patients' files. CDUS was performed to evaluate the resistive index (RI), parenchymal thickness, and parenchymal echogenicity before the operation, in the early postoperative period (7 days after catheter removal in group 1 and 7 days postoperatively in group 2), and during the midterm period (6 months postoperatively). Statistical significance was accepted at P<0.05.
  
  
  RESULTS
  The mean patient age was 47.54±13.26 years. There were 33 patients in group 1 and 28 patients in group 2. The mean follow-up duration was 10.71±1.2 months. There were no significant differences in demographic data between the two groups. The hospital stay was longer in group 1 than in group 2 (P=0.038). The mean operative time was shorter in group 2 than in group 1 (P=0.001). An increase in RI and a decrease in parenchymal thickness in the midterm follow-up period were noted when compared with the preoperative RI kidneys that had undergone operations in the lower pole.
  
  
  CONCLUSIONS
  Although tubeless PCNL was successful and was associated with a shorter hospital stay and less kidney damage in the short-term period compared with standard PCNL, both procedures may cause an almost equal degree of damage in the midterm.
authors.affiliation: 1 Department of Urology, Erzincan University School of Medicine , Erzincan, Turkey .
authors.forename: Yigit
authors.initials: Y
authors.lastname: Akin
authors.forename: Isil
authors.initials: I
authors.lastname: Basara
authors.forename: Selcuk
authors.initials: S
authors.lastname: Yucel
authors.forename: Hakan
authors.initials: H
authors.lastname: Gulmez
authors.forename: Mutlu
authors.initials: M
authors.lastname: Ates
authors.forename: Aliseydi
authors.initials: A
authors.lastname: Bozkurt
authors.forename: Baris
authors.initials: B
authors.lastname: Nuhoglu
authors.forename: Tibet
authors.initials: T
authors.lastname: Erdogru
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007668:Kidney / Q000000981:diagnostic imaging / Q000502:physiology / Q000601:surgery; D007669:Kidney Calculi / Q000601:surgery*; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods; D012189:Retrospective Studies; D014463:Ultrasonography