['• To identify additional factors that might improve the diagnosis of ureteric stones using ultrasonography (US) as the primary diagnostic method.', '• We performed a retrospective study of 228 patients who underwent rigid ureterorenoscopy (URS) for obstructive ureteric stones. • Patient age, sex, body mass index (BMI) and stone location and size were recorded. • All patients underwent US for stone detection before surgery. • If no cause of the flank pain was found by US, computer tomography (CT) was performed to confirm the absence of ureteric stones.', '• In 57 (25%), 15 (6.6%) and 156 (68.4%) patients a stone was localized on the proximal, mid- and distal ureter, respectively. • In 96 (42.1%), 122 (53.5%) and 10 (4.4%) patients the stone measured 0-5, 6-10 and >10 mm, respectively. • The mean (range) BMI of the patients was 24.7 (17.3-37.2) kg/m(2). • The overall stone detection rate using US was 86.4% overall, and 96.4% in adults ≤ 35 years. In 72/197 patients (36.5%) the stones found using US measured ≤ 5 mm and in 24/31 patients (77.4%) the stones found using CT measured ≤ 5 mm. • Age (P= 0.008), stone size (P < 0.001) and BMI (P= 0.013) were factors that independently affected ureteric stone diagnosis using US.'] Is in young adults with a low body mass index ultrasonography sufficient as a diagnostic tool for ureteric stones?