Application of twinkling artifact in ultrasonographic diagnostics of nephrolithiasis
Małgorzata Placzyńska, Anna Wachnicka-Bąk, Anna Jung
Twinkling artifact is a phenomenon used in ultrasound diagnostics including color Doppler. The look of the twinkling artifact depends majorly on the settings of the ultrasound scanner. This sign usually accentuates when the frequency of the transmitted ultrasonic beam is low and Doppler scale settings are high. Although this artifact is gaining more applications in ultrasound diagnostics, it is still unfamiliar phenomenon. It might be helpful in diagnostics of cholelithiasis and biliary lithiasis, adenomyomatosis and any parenchymal calcification in other organs. Application of twinkling artifact can also detect bowel gas or metallic foreign bodies. However, this artifact is used the most often to identify deposits in the urinary tract. Compared with X-ray of the abdomen and urography, ultrasonography with application of twinkling artifact can detect about 80% cases of urolithiasis. The concrement structure, its roughness and size are the most important factors involved in the development of this phenomenon. Twinkling artifact enables an early detection of calculus without acoustic shadow, deposits of small size and those located in the ureter. There is a suggestion that the presence or absence of color comet-tail artifact also depends on the chemical composition of the stone. Ultrasound enriched with application of the twinkling artifact should be an initial examination in the diagnostics of urolithiasis, in monitoring of the calculus evolution and in assessment of stones excretion after ESWL procedure.