title: Quantitative Evaluation of the Effects of Urinary Stone Composition and Size on Color Doppler Twinkling Artifact: A Phantom Study.
abstract: OBJECTIVE
  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 (rTAI= 0.801, rTAL= 0.838, rTAW= 0.584, respectively; P <.05).
  
  
  CONCLUSIONS
  The appearance of TA in association with urinary stones is highly dependent on stone composition and size.
authors.affiliation: Department of Ultrasound, Qilu Hospital, Shandong University, Jinan, China.
authors.forename: Mengmeng
authors.initials: M
authors.lastname: Shang
authors.affiliation: Department of Ultrasound, Qilu Hospital, Shandong University, Jinan, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Sun
authors.affiliation: Department of Ultrasound, Qilu Hospital, Shandong University, Jinan, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of Ultrasound, Qilu Hospital, Shandong University, Jinan, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Ultrasound, Qilu Hospital, Shandong University, Jinan, China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Shi
authors.affiliation: Department of Ultrasound, Qilu Hospital, Shandong University, Jinan, China.
authors.forename: Song
authors.initials: S
authors.lastname: Ning
authors.affiliation: Department of Ultrasound, Qilu Hospital, Shandong University, Jinan, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Cheng
mesh_terms: D016477:Artifacts; D005069:Evaluation Studies as Topic; D006801:Humans; D019047:Phantoms, Imaging; D018615:Ultrasonography, Doppler, Color / Q000379:methods*; D014545:Urinary Calculi / Q000737:chemistry* / Q000000981:diagnostic imaging*
keywords: composition; size; twinkling artifact; ultrasonography; urinary stone