<prompt> Contrast media used in ultrasound isUltraffinHexanolUrograffinEchovist  <response>: D. i.e. Echovist 39- 42 - Textbook of colour Doppler Imaging S.K. Bhargava Iohexol used in Myelography Contrast agent ECHOVIST have been used to evaluate tubal potency in infertility and ureteric reflux in children with renal tract infectionsContrast agents in Ultrasound Contrast agents increases shift frequency and echo strength determines the visualization hence act as echoenhancers Echo- enhancers are microbubbles - levovist, optisan, sonovue Range of ultrasound frequencies that are used for clinical diagnosis microbubbles at1 - 7 m diameter do not diffuse across the endothelium 