title: Biomedical Imaging in Implantable Drug Delivery Systems.
abstract: Implantable drug delivery systems (DDS) provide a platform for sustained release of therapeutic agents over a period of weeks to months and sometimes years. Such strategies are typically used clinically to increase patient compliance by replacing frequent administration of drugs such as contraceptives and hormones to maintain plasma concentration within the therapeutic window. Implantable or injectable systems have also been investigated as a means of local drug administration which favors high drug concentration at a site of interest, such as a tumor, while reducing systemic drug exposure to minimize unwanted side effects. Significant advances in the field of local DDS have led to increasingly sophisticated technology with new challenges including quantification of local and systemic pharmacokinetics and implant- body interactions. Because many of these sought-after parameters are highly dependent on the tissue properties at the implantation site, and rarely represented adequately with in vitro models, new nondestructive techniques that can be used to study implants in situ are highly desirable. Versatile imaging tools can meet this need and provide quantitative data on morphological and functional aspects of implantable systems. The focus of this review article is an overview of current biomedical imaging techniques, including magnetic resonance imaging (MRI), ultrasound imaging, optical imaging, X-ray and computed tomography (CT), and their application in evaluation of implantable DDS.
authors.forename: Haoyan
authors.initials: H
authors.lastname: Zhou
authors.forename: Christopher
authors.initials: C
authors.lastname: Hernandez
authors.forename: Monika
authors.initials: M
authors.lastname: Goss
authors.forename: Anna
authors.initials: A
authors.lastname: Gawlik
authors.affiliation: Department of Radiology, Case Western Reserve University, 11100 Euclid Ave, Cleveland, OH, 44106-5056, USA. Agata.exner@case.edu.
authors.forename: Agata A
authors.initials: AA
authors.lastname: Exner
mesh_terms: D000818:Animals; D003952:Diagnostic Imaging / Q000379:methods*; D016503:Drug Delivery Systems / Q000379:methods; D004343:Drug Implants / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D006801:Humans; D008279:Magnetic Resonance Imaging; D061848:Optical Imaging; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography
chemical_list: D004343:Drug Implants