Investigating the clinical significance of twinkling artifacts in patients with urolithiasis smaller than 5 mm.

PURPOSE

Our aim was to evaluate the effectiveness of twinkling artifacts (TA) in detecting calculi <5 mm in diameter in patients with renal colic pain who had undergone urinary grayscale ultrasonography (US) and computed tomography (CT) imaging assays.

MATERIALS AND METHODS

In this retrospective study, a total of 76 calculi <5 mm detected in 60 patients were evaluated. Whole data were established using an ultrasound (US) probe at frequencies 1.5-4.5 MHz and noncontrast CT. In US, echogenicity and posterior-shadow (PS) parameters were evaluated and compared with color-Doppler ultrasonography (CDUS) and CT signs.

RESULTS

The mean size of measured calculi was 3.9 ± 0.8 mm (range 2-5 mm). The calculus localization rates detected by CT imaging were as follows: kidneys (n = 61, 80.3 %), proximal ureter (n = 4, 5.3 %), middle ureter (n = 3, 3.9 %) and distal ureter (n = 8, 10.5 %). CT detected the calculus in all 76 cases. There was a statistically significant difference in US-CT and CDUS-CT comparisons (p < 0.001 and p = 0.023, respectively); however, no difference was found when comparing both US methods with CT (p = 0.083).

CONCLUSIONS

TA can be regarded as a significant marker of urolithiasis, and co-operative usage of Doppler and grayscale methods can yield satisfactory results comparable with CT.