The efficacy of gadobenate dimeglumine (Gd-BOPTA) at 3 tesla in brain magnetic resonance imaging - Comparison to 1.5 tesla and a standard gadolinium chelate using a rat brain tumor model

Objectives: The objectives of this study were to analyze the differences in contrast enhancement using gadobenate dimeglumine (Gd-BOPTA or MuitiHance) at 3 T versus 1.5 T and to compare Gd-BOPTA with a standard gadolinium chelate, gadopentetate dimeglumine (GdDTPA 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.