Open AccessA dual CT‐MR dendrimer contrast agent as a surrogate marker for convection‐enhanced delivery of intracerebral macromolecular therapeutic agents
Author(s) -
Regino Celeste Aida S.,
Walbridge Stuart,
Bernardo Marcelino,
Wong Karen J.,
Johnson Dennis,
Lonser Russell,
Oldfield Edward H.,
Choyke Peter L.,
Brechbiel Martin W.
Publication year - 2008
Publication title -
contrast media & molecular imaging
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.714
H-Index - 50
eISSN - 1555-4317
pISSN - 1555-4309
DOI - 10.1002/cmmi.223
Subject(s) - dendrimer , in vivo , chemistry , attenuation , in vitro , nuclear medicine , nuclear magnetic resonance , biomedical engineering , materials science , medicine , biochemistry , physics , biology , microbiology and biotechnology , optics
The feasibility of using Gd dendrimer‐based macromolecules (Gd‐G8 dendrimer) as a dual CT and MR contrast agent for monitoring convection‐enhanced delivery of therapy in the brain is evaluated both in vitro and in vivo with optimal dosing established. In vitro CT attenuation values of the Gd‐based agents (∼6.0 HU m M −1 ) were ∼1.6 times greater than iodine‐based agents and the attenuation of the Gd‐DTPA was comparable to Gd‐G8 dendrimer. Visible enhancement was observed on both CT and MR using Gd‐G8 dendrimer over a range of 23–78 m M ; however, a concentration of at least 47 m M in Gd was required for adequate delineation of the injection site on both CT and MR. MR offers greater sensitivity than CT in estimating the volume of distribution ( V d ) and effectively quantified the agent's concentration and diffusion using T 1 mapping at much lower concentrations of Gd (<10 m M in [Gd]). Copyright © 2008 John Wiley & Sons, Ltd.