Title:Biomedical Imaging in Implantable Drug Delivery Systems
VOLUME: 16 ISSUE: 6
Author(s):Haoyan Zhou, Christopher Hernandez, Monika Goss, Anna Gawlik and Agata A. Exner
Affiliation:Department of Radiology, Case Western Reserve University, 11100 Euclid Ave, Cleveland, OH, 44106-5056, USA.
Keywords:Biomaterials, drug delivery, fluorescence imaging, implant, MRI (magnetic resonance imaging), scaffold, ultrasound
imaging, X-ray CT Imaging.
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.
