Quantitative Evaluation of the Effects of Urinary Stone Composition and Size on Color Doppler Twinkling Artifact: A Phantom Study

Abstract

Objectives: The present study was conducted to quantitatively evaluate the influence of urinary stone composition and size on color Doppler twinkling artifact.

Methods: Calcium oxalate monohydrate (COM), apatite, L-cystine, and uric acid (UA) stone phantoms with 10 different sizes were prepared artificially and embedded in the renal sinus of porcine kidneys in vitro. Color Doppler ultrasound scanning was performed on the phantoms and TA pictures were recorded. The length of the twinkling artifact (TAL) and width of twinkling artifact (TAW) were measured. The color pixels representing twinkling artifact intensity (TAI) were calculated.

Results: There were significant differences in the appearance of TA among the four types of stone phantoms (P < .05). The mean value of TAI of UA stones was the strongest, followed by L-cystine, apatite, and COM. A significantly positive correlation was found between TA and stone size (r_TAI = 0.801, r_TAL = 0.838, r_TAW = 0.584, respectively; P <.05).

Conclusions: The appearance of TA in association with urinary stones is highly dependent on stone composition and size.

Keywords: composition; size; twinkling artifact; ultrasonography; urinary stone.