Review ArticlesUltrasound in Radiology From Anatomic, Functional, Molecular Imaging to Drug Delivery and Image-Guided TherapyKlibanov, Alexander L. PhD*†; Hossack, John A. PhD†Author Information From the *Cardiovascular Division, Robert M. Berne Cardiovascular Research Center, School of Medicine, and †Department of Biomedical Engineering, University of Virginia, Charlottesville VA. Received for publication April 5, 2015; and accepted for publication, after revision, May 12, 2015. Conflicts of interest and source of funding: Supported by National Institutes of Health via EB016752, EB001826, EB002349, HL090700, HL111077, CA102880, and DK093841. A.L. Klibanov is a co-founder and minority shareholder of Targeson Inc, a startup in the area of preclinical molecular ultrasound imaging. J.A. Hossack reports no conflicts of interest. Supplemental digital contents are available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Web site (www.investigativeradiology.com). Correspondence to: Alexander L. Klibanov, PhD, UVA CVRC, PO Box 801394, Charlottesville, VA 22908–1394. E-mail: email@example.com; firstname.lastname@example.org. Investigative Radiology: September 2015 - Volume 50 - Issue 9 - p 657-670 doi: 10.1097/RLI.0000000000000188 Buy SDC Metrics Abstract During the past decade, ultrasound has expanded medical imaging well beyond the “traditional” radiology setting: a combination of portability, low cost, and ease of use makes ultrasound imaging an indispensable tool for radiologists as well as for other medical professionals who need to obtain imaging diagnosis or guide a therapeutic intervention quickly and efficiently. Ultrasound combines excellent ability for deep penetration into soft tissues with very good spatial resolution, with only a few exceptions (ie, those involving overlying bone or gas). Real-time imaging (up to hundreds and thousands of frames per second) enables guidance of therapeutic procedures and biopsies; characterization of the mechanical properties of the tissues greatly aids with the accuracy of the procedures. The ability of ultrasound to deposit energy locally brings about the potential for localized intervention encompassing the following: tissue ablation, enhancing penetration through the natural barriers to drug delivery in the body and triggering drug release from carrier microparticles and nanoparticles. The use of microbubble contrast agents brings the ability to monitor and quantify tissue perfusion, and microbubble targeting with ligand-decorated microbubbles brings the ability to obtain molecular biomarker information, that is, ultrasound molecular imaging. Overall, ultrasound has become the most widely used imaging modality in modern medicine; it will continue to grow and expand. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.