Archivio Italiano di Urologia e Andrologia 2015; 87, 1 38 ORIGINAL PAPER The effect of inclined position on stone free rates in patients with lower caliceal stones during SWL session Basri Cakiroglu 1 , Orhun Sinanoglu 2 , Tuncay Tas 3 , Ismet Aydin Hazar 3 , Mustafa Bahadir Can Balci 3 1 Hisar Intercontinental Hospital Department of Urology, Istanbul, Turkey; 2 Maltepe University Medical School, Department of Urology, Istanbul, Turkey; 3 Taksim Training and Research Hospital, Department of Urology, Istanbul, Turkey. Objective: To compare the outcomes of shock wave lithotripsy (SWL) combined with inclined position and SWL alone in patients with lower pole calyx stones. Methods: Seven hundred forty patients who underwent SWL treatment for lower pole renal stones with a total diameter of 2 cm or less were prospectively randomized into two groups. They were comparable in terms of age, sex, and stone diameters. Patients with lower calyceal stones (4-20 mm) were randomized to SWL (368 patients) or SWL with simultaneous inclination (372 patients) with 30o head down Trendelenburg position). Shock wave and session numbers were standardized according to stone size. Additional standardized shock waves were given to patients with stone fragments determined by kidney uri- nary bladder film and ultrasound at weeks 1, 4, 10. Results: The overall stone free rate (SFR) was 73% (268/368) in patients with SWL alone and 81% (300/372) in SWL with inclination at the end of 12 th week (p = 0.015). No significant adverse events were noted in both treatment groups. Conclusion: Simultaneous inclination of patients during SWL session increase SFR in lower caliceal stones signifi- cantly compared to SWL treatment alone. KEY WORDS: Lower pole calyx stones; Shock wave lithotripsy; Inclined position; Stone free rate. Submitted 25 September 2014; Accepted 30 November 2014 Summary No conflict of interest declared. clearance of lower calyceal stones after SWL seems diffi- cult, SWL still continues to be the first choice therapy for patients with lower calyceal stones of any sizes as it is the non-invasive and easily available treatment option (6, 7). Investigators tried to increase stone-free rates in lower calyceal stones with some maneuvers, such as controlled inversion therapy with percussion after SWL or irrigation during treatment (4, 5).When outcomes of these auxil- iary procedures accompanying SWL were classified by stone size (< 1 cm diameter, 1-2 cm, and > 2 cm),stone- free rates after SWL treatment were found 74%, 56% and 33% respectively (8). Contrast opinions also were reported in other studies claiming that controlled inver- sion therapy did not improve results for people who underwent shock wave lithotripsy for lower pole kidney stones, among them diuresis and inversion did not sig- nificantly improve stone free rates in a series (4, 9). Despite several studies supporting the benefit of auxil- iary procedures, there is limited evidence suggesting that percussion, diuresis and especially inversion therapy may be beneficial for patients with lower calyceal stones after shock wave lithotripsy. Therefore, we compared the effectiveness of inclination to regular position during SWL for eliminating lower calyx calculi. We suggest that a 30º head down inclination would overcome the gravi- tational effect of lower pole calyx that will eliminate residual fragments than usual session alone at 3 months without altering confort or hemodynamics of the patient. MATERIALS AND METHODS Seven hundred forty patients between August 2006- October 2013 who underwent SWL treatment for radio- logically identified lower pole radiopaque renal calculi with a total diameter of 2 cm or less were prospectively randomized into two groups. The study protocol was reviewed and approved by the institutional ethics com- mittee. Participants were enrolled if they were 18 years of age or older having solitary renal calculi between 4 and 20 mm, and gave consent to randomization. Exclusion criteria were non lower calyceal stones of the same side, renal anatomical deformities such as urethral stricture or ureteropelvic junction obstruction, concomitant distal DOI: 10.4081/aiua.2015.1.38 INTRODUCTION The prevalence of kidney stones is 2% to 3% in the general population), but the relative incidence of lower calyceal stones remains unclear (1). Shock wave lithotripsy (SWL) is widely accepted as the gold standard treatment for kidney stones less than 2 cm diameter. It is a non-invasive procedure, requires minimum anaesthe- sia, and with high patients preference. The incidence of lower calyceal kidney stones treated with SWL has risen as time passed after the primitive SWL devices came into use (2). Afterwards various studies have suggested the use SWL for these stones (2-5), However, although the