The contrast medium, Sonazoid, consists of billions of microscopic spheres and is administered intravenously. The microspheres are smaller than capillaries but do not leak from blood vessels. Sonazoid reflects ultrasonic waves and the microspheres produce a well detected acoustic signal. It is therefore ideal for hypervascular tumors such as clear cell carcinoma. Contrast-enhanced doppler US was used in five patients when the tumor margin was unclear to the surgeon on conventional B-mode US. In these cases, injection of Sonazoid produced a well visible rim of blood vessels around the tumor, and allowed the surgeon to proceed safely with the procedure. In addition, it assisted in selective clamping of the arteries supplying the tumor as it clearly confirmed ischemia of the tumor area.
In conclusion, intraoperative contrast-enhanced Doppler US was a useful adjunct tool in robotic partial nephrectomy, when tumors had unclear margins on conventional B-mode US. Of note, Sonazoid is contraindicated in patients with egg allergy and is associated with a low incidence of side effects such as diarrhea, albuminuria, and neutropenia.
Presented by: Fumiya Hongo - Department of Urology, Kyoto Prefectural University of Medicine, Japan
Authors: Fumiya Hongo, Atsuko Fujihara, Yuta Inoue, Nomura Takeshi, Tsukasa Narukawa, Yasuyuki Naitoh, and Osamu Ukimura - Department of Urology, Kyoto Prefectural University of Medicine, Japan
Written by: Dr. Shlomi Tapiero, Department of Urology, University of California-Irvine, medical writer for UroToday.com. at the 36th World Congress of Endourology (WCE) and SWL - September 20-23, 2018 Paris, France