Yeu-Sheng Tyan2026-10-162026-10-162004-01-01Pure ID: 15076129Pure UUID: 1ed7c366-0ff4-4721-b828-6d6f25f6a4f710.1016/S0929-6441(09)60097-7https://www.scopus.com/pages/publications/33644762729https://scholars.csmu.edu.tw/handle/123456789/34467Background: The color Doppler twinkling artifact is manifested as a rapidly changing mixture of red and blue colors behind a strongly reflecting structure. The effects of the roughness of the reflecting surface and the Doppler angle on the intensity of the twinkling artifact have never been quantitatively reported before. In this study, a simple in vitro system with reproducible results was established to observe the effects of these two factors on the strength of the twinkling artifact. Materials and methods: Six different grits of water sandpapers were simultaneously scanned in a water bath with a fixed probe. In part 1, the computer calculated the pixels of color Doppler twinkling artifact behind each water sandpaper. In part 2, the signals of twinkling artifacts with different sandpaper sizes and different Doppler angles were recorded and analyzed. Results: In part 1, the twinkling artifact was identified persistently and more intensely behind water sandpapers that had greater surface roughness. In part 2, different Doppler angles revealed less obvious effects on the strength of the twinkling artifacts in a certain range of angles, but would drastically decrease the intensity in the steeper angles. Conclusions: We have established a simple model system with water sandpapers for the evaluation of the twinkling artifact. Our data confirmed the assumption that the roughness of the reflecting surface is directly related to the strength of the twinkling artifact. In addition, the Doppler angle affects the intensity of the artifact, but only in the steeper angles.6enjournal article