Can Doppler ultrasonography twinkling artifact be used as an alternative imaging modality to non-contrast-enhanced computed tomography in patients with ureteral stones? A prospective clinical study.

We aimed to evaluate the use of twinkling artifact (TA) on color Doppler ultrasonography (USG) as an alternative imaging modality to non-contrast-enhanced computed tomography (CT) in patients with ureteral stones in this prospective study. Totally, 106 consecutive patients who had been diagnosed with ureterolithiasis by CT were enrolled in this prospective study. A urinary system color Doppler ultrasonography was performed on the same day with CT by an experienced radiologist who was blinded to the CT scan. TA was graded as 0, 1 and 2. The overall specificity of TA was calculated according to the NCCT as a gold standard method. The size, side and localization of stone and the demographic characteristics of patients were compared with twinkling positivity. TA on color Doppler USG was detected in 92 (86.8 %) patients. Statistically significant difference was found between the TA and localization of ureteral stones (p = 0.044). When we sub-grouped the patients according to the TA grades as 0, 1 and 2, 14 patients were with TA grade 0, 55 with TA grade 1 and 37 with TA grade 2. The mean stone size of groups was significantly different (p = 0.012). Bigger and proximal ureteral stones tended to have more TA on color Doppler USG. TA on color Doppler USG could be a good and safe alternative imaging modality with comparable results between NCCT. It could be useful for the diagnosis and follow-up of patients with ureterolithiasis.