title: Is pelvicaliceal anatomy a risk factor for stone formation in patients with solitary upper caliceal stone?
abstract: OBJECTIVE
  To investigate the effect of pelvicaliceal anatomy on stone formation in patients with solitary upper caliceal stones.
  
  
  METHODS
  The records of patients with solitary upper caliceal stones between 1996 and 2004 were reviewed. After the exclusion of patients with hydronephrosis, major anatomic abnormalities, noncalcium stones, metabolic abnormalities, history of recurrent stone disease, multiple stones, and previous renal surgery, 42 patients (24 male, 18 female) and 42 healthy subjects (22 male, 20 female) with normal results on intravenous pyelography (IVP) were enrolled into the study. With a previously described formula, upper pole infundibulopelvic angle (IPA), infundibular length (IL) and width (IW), and pelvicaliceal volume of the stone-bearing and contralateral normal kidney of patients and bilateral normal kidneys of healthy subjects were measured from IVP.
  
  
  RESULTS
  Forty-two stone-bearing and 126 normal kidneys (42 contralateral, 84 healthy) were assessed. The mean stone size was 153.47 mm2 (range, 20 to 896 mm2). There were no statistically significant differences in terms of upper caliceal specifications between stone-bearing and normal kidneys. The mean (+/- standard deviation) pelvicaliceal volume of 42 stone-bearing and 126 normal kidneys was 2455.2 +/- 1380.2 mm3 and 1845.7 +/- 1454.8 mm3, respectively (P = 0.019). These values were 2114 +/- 2081.5 mm3 (P = 0.34) and 1709.5 +/- 989.1 mm3 (P = 0.001) for contralateral normal kidneys (n = 42) and normal kidneys of healthy subjects (n = 84), respectively.
  
  
  CONCLUSIONS
  Explanation of the etiology of the upper caliceal stone by the anatomic features is very difficult, and these caliceal anatomic variables (IPA, IL, IW) seem not to be a significant risk factor for stone formation in the upper calyx.
authors.affiliation: Department of Urology, School of Medicine, Gazi University, Ankara, Turkey.
authors.forename: Cenk
authors.initials: C
authors.lastname: Acar
authors.forename: Bora
authors.initials: B
authors.lastname: Küpeli
authors.forename: Serhat
authors.initials: S
authors.lastname: Gürocak
authors.forename: Turgut
authors.initials: T
authors.lastname: Alkibay
authors.forename: Cağri
authors.initials: C
authors.lastname: Güneri
authors.forename: Seçil
authors.initials: S
authors.lastname: Ozkan
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Bozkirli
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000209:etiology*; D007670:Kidney Calices / Q000033:anatomy & histology*; D008297:Male; D012307:Risk Factors