Objective: The first goal of this study is to compare gadofosveset trisodium--a gadolinium agent that reversibly binds to albumin--to an extracellular contrast agent (Gd-DOTA) for the detection of multiple sclerosis lesions. The second goal is to determine the best postinjection time for the detection of contrast-enhanced lesions.
Methods: Nine patients underwent 2 MRI examinations, respectively, after Gd-DOTA (0.1 mmol/kg) and gadofosveset trisodium (0.03 mmol/kg) administration. Axial T1 spin-echo-weighted images were acquired at several time points after injection (4 minutes for Gd-DOTA, and 4, 8, 12, 16, 20 minutes, 1 hour, and 4 hours for gadofosveset trisodium). Images were analyzed by 4 neuroradiologists who marked the contrast-enhanced lesions and, for each marked lesion, chose the acquisition they preferred and segmented the lesion on their preferred acquisition.
Results: The 4-hour gadofosveset trisodium acquisition was ranked best for the 3 tasks: contrast-enhanced lesions were seen by more readers, they preferred this acquisition, and improvements of the signal enhancement (125%) and of the contrast-to-noise ratio (73%) vs Gd-DOTA at 4 minutes were observed (p < 0.05).
Conclusion: Gadofosveset trisodium after 4 hours significantly improves the number of detected contrast-enhanced multiple sclerosis lesions as compared to Gd-DOTA after 4 minutes, even though the injected dose of gadolinium was two-thirds lower.