Objectives: The objectives of this study were to analyze the differences in contrast enhancement using gadobenate dimeglumine (Gd-BOPTA or MultiHance) at 3 T versus 1.5 T and to compare Gd-BOPTA with a standard gadolinium chelate, gadopentetate dimeglumine (Gd-DTPA or Magnevist), at 3 T in a rat glioma model.
Materials and methods: Twelve rats with surgically implanted gliomas were randomized to either comparing Gd-BOPTA at 1.5 T versus 3 T (n=7) or comparing Gd-BOPTA and Gd-DTPA at 3 T (n=5). Matched T1-weighted spin-echo techniques were used for both comparisons and the order of examinations was randomized. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and lesion enhancement (LE) were evaluated using a region-of-interest analysis. A veterinary histopathologist evaluated all brain specimens.
Results: In the evaluation of Gd-BOPTA at 3 T and 1.5 T, there were significant increases in SNR, LE, and CNR at 3 T. Average increases in brain and tumor SNR were 93% (P<0.0001) and 92% (P<0.0001), respectively. CNR increased by 121% (P<0.0001). Comparison of Gd-BOPTA and Gd-DTPA at 3 T demonstrated significantly higher CNR and LE with Gd-BOPTA. CNR increased by 35% (P=0.002). LE increased by 44% (P=0.03).
Conclusions: Gd-BOPTA provides significantly higher CNR at 3 T compared with 1.5 T and also demonstrates significantly higher CNR when compared with a standard Gd-chelate at 3 T. As a result of transient protein binding, Gd-BOPTA may be superior to standard gadolinium chelates in neurologic imaging at 3 T.