Predictive parameters for medical expulsive therapy in ureteral stones: a critical evaluation

To evaluate the predictive value of some certain radiological as well as stone-related parameters for medical expulsive therapy (MET) success with an alpha blocker in ureteral stones. A total 129 patients receiving MET for 5 to 10 mm ureteral stones were evaluated. Patients were divided into two subgroups where MET was successful in 64 cases (49.61%) and unsuccessful in 65 cases (50.39%). Prior to management, stone size, location, position in the ureter, degree of hydronephrosis, diameter of ureteral lumen proximal to the stone, ureteral wall thickness along with patient's demographics including body mass index (BMI) values were evaluated and recorded. The possible predictive values of these parameters for stone expulsion (and stone expulsion time) were evaluated in a comparative manner between two groups. The overall mean patient age and stone size values were 38.02 ± 0.94 years and 40.31 ± 1.13 mm(2), respectively. Regarding the predictive values of these parameters for MET-success, while stone size and localization, degree of hydronephrosis, proximal ureteral diameter and ureteral wall thickness were found to be highly predictive for MET-success, patients age, BMI values and stone density had no predictive value on this aspect. Our findings indicated that some stone and anatomical factors may be used to predict the success of MET in an effective manner. With this approach unnecessary use of these drugs that may cause a delay for stone removal will be avoided and the possible adverse effects of obstruction as well as stone-related clinical symptoms could be minimized.