JOURNAL OF ENDOUROLOGY Volume 21, Number 1, January 2007 © Mary Ann Liebert, Inc. DOI: 10.1089/end.2006.0156 Is Stone Clearance after Shockwave Lithotripsy in Patients with Solitary Upper-Caliceal Stone Influenced by Anatomic Differences in the Pelvicaliceal System? BORA KÜPELI, M.D., CENK ACAR, M.D., SERHAT GÜROCAK, M.D., ÇAG ˘ RI GÜNERI, M.D., ÜSTÜNOL KARAOGLAN, M.D., and IBRAHIM BOZKIRLI, M.D. ABSTRACT Purpose: We investigated the effect of pelvicaliceal differences on stone clearance after extracorporeal shock- wave lithotripsy (SWL) in patients with solitary upper-caliceal stones. Patients and Methods: The clinical records of patients with solitary upper-caliceal stones who underwent SWL between 1996 and 2004 were reviewed. After excluding patients with hydronephrosis, significant ana- tomic abnormalities, non-calcium stones, metabolic abnormalities, recurrent stone disease, multiple stones, and previous renal surgery, 42 patients with a mean stone size of 153.47 mm 2 (range 20–896 mm 2 ) were en- rolled in this study. They were divided into three groups according to stone burden (group 1 100 mm 2 , group 2 101 mm 2 –200 mm 2 , and group 3 200 mm 2 ). Upper-pole infundibulopelvic angle (IPA), infundibular length (IL), and infundibular width (IW) were measured from intravenous urograms. Results: Of the total, 29 patients (69%) were stone free after SWL treatment. The differences in the upper- pole IPA, IL, and IW of stone-free patients and patients with residual stones were not statistically significant (P  0.85, P  0.89, and P  0.37, respectively). Again, there were no statistically significant differences in terms of upper IPA, IW, and IL in comparing the three groups divided by initial stone size. Conclusion: Upper-caliceal anatomy does not exert a significant impact on stone clearance after SWL for isolated upper-caliceal stones. To best of our knowledge, this is the first study to investigate the effects of pelvi- caliceal anatomy on SWL treatment for upper-caliceal stones, so there is a need for further investigations to confirm our findings. INTRODUCTION E XTRACORPOREAL SHOCKWAVE LITHOTRIPSY (SWL) has been used widely as the primary treatment mo- dality for most renal and ureteral calculi since its first applica- tion in the clinical setting by Chaussy et al in 1980. 1 Owing to technologic advances and worldwide satisfaction with the first lithotripter, the Dornier HM3, several companies have designed different generations of lithotripters, which have been evalu- ated with regard to efficacy and complications. 2,3 With the ac- cumulation of SWL treatment data, studies focused on stone- related factors such as stone burden, composition, and location and patient factors such as infection, obstruction, and renal anat- omy as determinants of outcome. The success of this treatment modality depends on these factors, and in different large stud- ies, stone-free rates after SWL treatment for lower-, middle-, and upper-caliceal stones were 48% to 58%, 43% to 76%, and 45% to 83%, respectively. 4-6 Recent studies demonstrated that unfavorable renal anatomic features might inhibit stone clearance after SWL in patients with lower-caliceal stones. Sampaio and colleagues 7 reported that these adverse factors were a lower infundibulopelvic angle (IPA) of 90°, an infundibular width (IW) 4 mm, and com- plex caliceal anatomy. After this pioneering study, other in- vestigators 8,9 concluded that caliceal anatomy was an impor- tant risk factor for failure of lower-pole stone clearance after SWL. On the other hand, the effects of upper-caliceal anatomy in patients with stones in the upper part of the kidney have not been well evaluated to date. Because studies performed with three-dimensional resin endocasts of renal collecting systems Department of Urology, Gazi University School of Medicine, Ankara, Turkey. 18