Predictors of success for stone fragmentation and stone-free rate after extracorporeal shockwave lithotripsy in the treatment of upper urinary tract stones.
OBJECTIVE
To evaluate factors affecting the success rate of stone fragmentation and stone-free rate after extracorporeal shockwave lithotripsy (SWL) in treatment of upper urinary tract stones.


METHODS
A total of 121 patients with upper urinary tract calculi underwent SWL treatment.


RESULTS
Success rate of stone fragmentation after SWL was 73.6% (89/121). In 89 patients who had success of breaking stones, 71 patients were followed up for the assessment of stone-free status, of whom 51 (71.8%) patients were stone-free at 3-month follow-up. Among four prognostic factors, including body mass index (BMI), stone size, stone position, and hydronephrosis, BMI and stone position had a significant impact on the success rate of stone fragmentation (P = .04 and U1: P = .0108, respectively). Among five prognostic factors of BMI, stone size, stone position, hydronephrosis, and times of SWL treatments, stone size was the only factor with significant impact on the stone-free rate (middle: P = .0229).


CONCLUSIONS
Our study suggests that stone fragmentation and stone-free rate after SWL treatment for upper urinary tract stones can be predicted.
Department of Urology, Osaka Medical College, Osaka, Japan. uro037@poh.osaka-med.ac.jp
Kiyoshi
K
Takahara
Naokazu
N
Ibuki
Teruo
T
Inamoto
Hayahito
H
Nomi
Takanobu
T
Ubai
Haruhito
H
Azuma
D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008096:Lithotripsy / Q000379:methods; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016896:Treatment Outcome; D014545:Urinary Calculi / Q000473:pathology / Q000628:therapy*