Related Experiment Video
Updated: Aug 29, 2026

MR Molecular Imaging of Prostate Cancer with a Small Molecular CLT1 Peptide Targeted Contrast Agent
Published on: September 3, 2013
Interstitial MR and CT lymphography with Gd-dTPA-co-alpha, omega-diaminoPEG(1450) and Gd-dTPA-co-1,6-diaminohexane
T S Desser1, D L Rubin, H Muller
1Department of Radiology, VA Palo Alto Health Care System, 3801 Miranda Ave, Palo Alto, CA 94304, USA.
Rationale And Objectives:
The authors assessed the efficacy of two gadolinium-based polymers used as lymphotrophic contrast media for computed tomography (CT) and magnetic resonance (MR) imaging.
Materials And Methods:
Two gadolinium-based polymers, gadolinium diethylenetriaminepentaacetic acid (DTPA)-co-1,6-diaminohexane (NC 22181) and Gd-DTPA-co-alpha, omega-diamino-polyethylene glycol(1450) (NC-66368), were formulated at a concentration of 80 mmol/L gadolinium. Doses of 0.1, 0.25, 1.0, or 2.0 mL per paw were administered subcutaneously into the hindpaws of normal rabbits. Spin-echo T1-weighted MR imaging (1.5 T) of rabbit popliteal and iliac nodes was performed before and immediately, 10 minutes, 2-3 hours, and 24 hours after injection. CT was performed 2-3 hours after injection of the high doses only.
Results:
MR imaging revealed prompt enhancement of the popliteal nodes with both polymers at doses of 0.25 mL and above. For doses of 1.0 mL or less per paw, nodal percentage enhancement was maximal at 2 hours and then declined at 24 hours. At the highest doses, however, a reservoir of subcutaneous contrast material remained at the injection site and resulted in peak enhancement at 24 hours. At CT, popliteal node enhancement was faintly visible 2-3 hours after the administration of NC 22181. At lower doses, no enhancement was appreciable at CT.
Conclusion:
At 80 mmol/L formulations, the two gadolinium-based polymers provide excellent popliteal nodal enhancement on MR images. In addition, high doses of one polymer (NC 22181) were sufficiently concentrated in popliteal nodes to be visible on CT scans. Thus, this agent may be useful for both CT and MR lymphography.

