Detection of UVJ stone confirmed with new Doppler finding and rapid intravenous hydration

Abstract

Detection of UVJ stone confirmed with new Doppler finding and rapid intravenous hydration Kwon Kim, Hyuk Joong Choi, Bo Seung Kang, Tai Ho Im Department of Emergency Medicine, Hanyang University Guri Hospital Twinkling artifact is new Doppler finding of ultrasonography for urinary calculi, which can help rule out or confirm the presence of stone in equivocal case. It appears as a rapidly alternating red and blue color Doppler signal behind stone. Quick bladder filling with rapid intravenous hydration provides better visualization of distal ureter and ureterovesical junction(UVJ) on transabdominal ultrasonography, particularly helpful in busy emergency department. With rapid intravenous hydration, we report a case of UVJ stone confirmed by twinkling artifact on transabdominal ultrasonography. Echogenic focus within collapsed bladder; Distinct echogenicity and weak posterior acoustic shadowing (A) Twinkling artifact(TWA) behind suspected stone with a fine heterogeneous broadband signal (B, C) A B C Intravenous infusion of normal saline 1.5 L for 15 min Distinct stone within dilated distal ureter near right UVJ (E) Urine jet flow from right UVJ with TWA(F) E In suspected stone, twinkling artifacts can help rule out or confirm the presence of a stone. Color Doppler twinkling artifacts can be considered an additional sonographic feature of urinary stones, and they may be useful in determining the presence of urinary stones especially urinary stones with indistinct echo difference and indiscrete posterior acoustic shadowing. With better visualization of distal ureter and ureterovesical junction(UVJ) on transabdominal sonography, quick bladder filling with rapid IV hydration very useful. Discussion Reference 1. Rahmouni A, Bargoin R, Herment A, et al. Color Doppler twinkling artifact in hyperechoic regions. Radiology 1996;199:269.271. 2. Lee JL, Kim SH, Cho JY, et al. Color and power Doppler twinkling artifacts from urinary stones: clinical observations and phantom studies. Am J Roentgenol 2001 ;176:1441.1445. 3. Chelfouh N, Grenier N, Higueret D, et al. Characterization of urinary calculi: in vitro study of “twinkling artifact” revealed by color-flow sonography. Am J Roentgenol 1998 ;171:1055.1060. 4. Sheafor DH, Hertzberg BS, Freed KS, et al. Nonenhanced helical CT and US in the emergency evaluation of patients with renal colic: prospective comparison. Radiology 2000; 217:792.797.