PERCUTANEOUS VASCULAR AND NONVASCULAR PUNCTURE UNDER US GUIDANCE - ROLE OF COLOR DOPPLER IMAGING

Although ultrasound guidance is extensively used in percutaneous inter ventional procedures, the limitations of B-mode, gray-scale sonographi c guidance can restrict clinical use. Little attention has been paid t o the use of color Doppler sonography during such procedures. There ar e several ways in which color Doppler sonography can facilitate percut aneous procedures that involve insertion of a needle or catheter. The advantages of color Doppler sonography include the following: (a) bett er visualization of the shaft and tip of the needle, especially in sol id, echogenic lesions, when the needle is moving, or when the beam-nee dle angle is narrow; (b) improved targeting of either vessels or nonva scular structures (ie, biliary ducts) to be punctured; (c) avoidance o f interposed vascular structures and highly vascular areas during punc ture of lesions; (d) improved visualization of poorly echogenic cathet ers, allowing proper placement; and (e) prompt detection of complicati ons, including active bleeding, after withdrawal of the needle.