BIPLANE COLOR-FLOW DUPLEX INTRAVENOUS INTRAVASCULAR ULTRASOUND FOR ARTERIAL VISUALIZATION

Purpose: To describe a feasibility study in a sheep model using an int ravascular ultrasound (IVUS) instrument in an intravenous position to produce color flow, B-mode images of arterial segments along with Dopp ler blood flow velocities. Methods: Four healthy adult male sheep were anesthetized for surgical exposure of the right external jugular vein . A 9.0F sheath was also introduced in the common femoral artery for a rteriography and device insertion. A 7.5-MHz ultrasound probe with 1-c m graduation markers was passed into the jugular vein. B-mode and colo r flow pictures were captured at aortic branches in cross and longitud inal sections, length measurements between aortic branches and Doppler spectral velocities were obtained. Guidewire, balloon, and stent mane uvers were monitored by the stationary intravenous IVUS probe. Results : High-quality visualization of the entire abdominal aorta and its bra nches was achieved in all animals. With the probe stationary in the ve na cava, a 1.5-cm linear segment of the aorta could be continuously ob served in both B-mode and color flow ultrasound scans. Insertion and i mplantation of a Palmaz balloon-expandable stent was guided by intrave nous IVUS alone. Selective catheterization of the right renal artery w as followed visually by moving the intravenous IVUS probe sequentially . Conclusions: Intravenous IVUS appears feasible as a guidance and mon itoring tool for endovascular interventions. While conventional IVUS p rovides, only cross-sectional images in B-mode, intravenous IVUS captu res color flow and Doppler velocity data as well. These added ultrasou nd modalities may offer potential advantages for guidance of endovascu lar procedures and endoleak detection.