title: Significance of lower-pole pelvicaliceal anatomy on stone clearance after shockwave lithotripsy in nonobstructive isolated renal pelvic stones.
abstract: OBJECTIVE
  To investigate the probable effect of lower-pole pelvicaliceal anatomy on stone clearance after shockwave lithotripsy (SWL) in patients with nonobstructive renal pelvic stones.
  
  
  METHODS
  The clinical records of patients with isolated renal pelvic stones who underwent SWL between 1996 and 2005 were reviewed. After excluding patients with obstruction leading to dilatation, major anatomic abnormalities, noncalcium stones, metabolic abnormalities, history of recurrent stone disease, multiple stones, and previous renal surgery, 153 patients were enrolled in the study. Lower pole infundibulopelvic angle (IPA) and infundibular length and width were measured from intravenous urography. Patients were classified into three groups according to stone burden (group 1, <100 mm(2); group 2, 101-200 mm(2); group 3, 201-400 mm(2)).
  
  
  RESULTS
  The mean stone size was 142.08+/-86.3 mm(2). Overall stone-free rate was 53.6%. Localization of clinically significant or insignificant residual fragments was in the lower calix, renal pelvis, and both in 50 (32.6%), 29 (18.9%), and 8 (5.2%) patients, respectively. There was no statistically significant difference in pelvicaliceal anatomic features except narrower IPA (P=0.02) in group 1 patients with residual stones.
  
  
  CONCLUSIONS
  The falling of stone fragments to the lower calix in spite of the ureter whether clinically significant or not after SWL of pelvic stones initially seems to be related to stone burden rather than lower caliceal anatomy. However, existence of a more narrow IPA in group 1 patients with residual fragments led us to believe that lower-pole IPA can play a role in stone clearance, especially for smaller stones, probably because of smaller residual fragment size or the more mobile nature of the primary stone.
authors.affiliation: Department of Urology, Gazi University School of Medicine, Ankara, Turkey.
authors.forename: Sinan
authors.initials: S
authors.lastname: Sozen
authors.forename: Bora
authors.initials: B
authors.lastname: Kupeli
authors.forename: Cenk
authors.initials: C
authors.lastname: Acar
authors.forename: Serhat
authors.initials: S
authors.lastname: Gurocak
authors.forename: Ustunol
authors.initials: U
authors.lastname: Karaoglan
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Bozkirli
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000473:pathology / Q000628:therapy*; D007682:Kidney Pelvis / Q000033:anatomy & histology*; D008096:Lithotripsy; D008297:Male; D008875:Middle Aged