Computed tomography findings predicting the success of silodosin for medical expulsive therapy of ureteral stones

Abstract

Aim of the study is to investigate the relationship between non-contrast computed tomography (NCCT) findings and stone expulsion rate with medical expulsive therapy (MET) using silodosin for ureteral stones in male adults. Between January 2014 and June 2015, we retrospectively reviewed the patient charts with uncomplicated ureteral stones on NCCT images, who were treated with silodosin for MET. Stone diameter, volume and hounsfield units (HU) measured by NCCT and treatment findings were noted at the end of treatment. Patients were divided into three groups according to the localization as distal, mid and proximal ureteral stones. NCCT and treatment findings were compared between MET success and failure groups in different localizations. Stone expulsion rate was 81.3% for 134 distal, 45.5% for 22 mid and 27.7% for 47 proximal stones. Stone diameter, volume, and HU were significantly lower for success groups with distal and proximal stones (p < 0.05). In ROC analysis the cut-off values for stone volume and HU were detected as 48.7 mm3 and 598 HU for success group with proximal stones. Stone expulsion rate was found to be 24 times more (OR = 24; p = 0.001) in patients with <598 HU and 14 times more (OR = 14; p = 0.002) in patients with <48.7 mm3 proximal stones. Lower stone diameter, volume and HU were significant predictors of success with silodosin for MET for ureteral stones. Patients with <598 HU and/or <48.7 mm3 proximal stones may be prescribed silodosin for MET.

Keywords

• Hounsfield units (HU)
• Medical expulsive therapy (MET)
• Non-contrast computed tomography (NCCT)
• Proximal ureteral stone
• Ureteral stone