title: The kidney: imaging with microbubble contrast agents.
abstract: Conventional ultrasonography of the kidney is faced by limitations due to the poor contrast of B-mode imaging for parenchymal disease and limited sensitivity of color Doppler for the detection of intracortical capillaries and deep pedicular vessels. Ultrasound contrast agents (USCAs) overcome these limitations, allowing the development of new applications for renal blood flow imaging and quantification. These improvements result from the increased acoustic response obtained from the microbubbles, as well as from the development of pulse sequences for bubble-specific imaging. In radiology, the liver has been considered as the primary target for contrast because USCAs allow both detection and characterization of focal lesions. The kidney has been less studied because USCA kinetics do not provide the same obvious potential for tumor characterization, and most clinical trials for contrast-enhanced renal imaging were conducted using color Doppler. Despite this, the kidney offers promising applications as USCAs improve the detection of abnormal microvascular and macrovascular disorders. Contrast-enhanced US may become the modality of choice for diagnosis of renal artery stenosis and detection of a perfusion deficit, as well as for characterization of indeterminate renal lesions, atypical cystic lesions, and the identification of acute pyelonephritis.
authors.affiliation: Department of Adult Radiology, Necker University Hospital, Paris, France. jean-michel.correas@nck.ap-hop-paris.fr
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Correas
authors.forename: Michel
authors.initials: M
authors.lastname: Claudon
authors.forename: François
authors.initials: F
authors.lastname: Tranquart
authors.forename: And Olivier
authors.initials: AO
authors.lastname: Hélénon
mesh_terms: D003287:Contrast Media / Q000493:pharmacokinetics*; D006801:Humans; D007668:Kidney / Q000098:blood supply; D007674:Kidney Diseases / Q000000981:diagnostic imaging*; D016030:Kidney Transplantation; D045423:Microbubbles; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000379:methods*
chemical_list: D003287:Contrast Media