Characterization of focal XXXX with superparamagnetic iron oxide-enhanced MR imaging: value of distributional phase T1-weighted imaging.

@entity1 @entity2695 @entity5 @entity409 @entity189 @entity201 @entity3 @entity157 @entity99
OBJECTIVE: To determine the potential value of distributional-phase T1-weighted ferumoxides-enhanced magnetic resonance (MR) imaging for tissue characterization of focal @entity409 . MATERIALS AND METHODS: Ferumoxides-enhanced MR imaging was performed using a 1.5-T system in 46 @entity1 referred for evaluation of known or suspected @entity99 . Seventy-three focal @entity409 (30 @entity157 ( @entity157 ), 12 @entity3 , 15 cysts, 13 @entity2695 , and three @entity201 ) were evaluated. MR imaging included T1-weighted double-echo gradient-echo (TR/TE: 150/4.2 and 2.1 msec), T2*-weighted gradient-echo (TR/TE: 180/12 msec), and T2-weighted turbo spin-echo MR imaging at 1.5 T before and after intravenous administration of ferumoxides (15 mmol/kg body weight). Postcontrast T1-weighted imaging was performed within eight minutes of infusion of the contrast medium (distributional phase). Both qualitative and quantitative analysis was performed. RESULTS: During the distributional phase after infusion of ferumoxides, unique enhancement patterns of focal @entity409 were observed for @entity2695 , @entity3 , and @entity157 . On T1-weighted GRE images obtained during the distributional phase, @entity2695 showed a typical positive enhancement pattern of increased signal; @entity3 showed ring enhancement; and @entity189 showed slight enhancement. Quantitatively, the signal-to-noise ratio of @entity2695 was much higher than that of other @entity5 (p <.05) and was similar to that of intrahepatic vessels. This finding permitted more effective differentiation between @entity2695 and other @entity5 . CONCLUSION: T1-weighted double-echo FLASH images obtained soon after the infusion of ferumoxides, show characteristic enhancement patterns and improved the differentiation of focal @entity409 .
