This study has measured the longitudinal and transverse (T* 2 ) relaxivity curves for ProHance (Gadoteridol), Vasovist (Gadofosveset) and deoxyhemoglobin at 1.5, 3.0, and 7.0 Tesla. The plots of R 1 versus both contrast agent and deoxyhemoglobin concentration were linear. The plots of R* 2 versus deoxyhemoglobin concentration showed a quadratic dependence. R* 2 versus contrast agent concentration showed a parabolic dependence with a minimum occurring at contrast agent concentrations of approximately 1.5 mM, corresponding to an accessible concentration in vivo. Monte Carlo simulations were performed to support the hypothesis that the minimum results from the susceptibility of the red blood cells being matched to the susceptibility of the plasma. Relaxivity values (s ؊1 mM ؊1 ) for R* 2 and R 1 for all agents and all three field strengths are given. Magn Reson Med 60:1313-1320, 2008.

DIEP flaps elevated on perforators with venae comitantes with direct venous connections to the main arborization of the superficial inferior epigastric vein are significantly associated with a very low incidence of flap venous congestion. Contrast-enhanced magnetic resonance angiography allows detailed appraisal of the venous anatomy, which may minimize the risk of DIEP flap venous insufficiency and the need for salvage procedures.

The results suggest that radiologic demonstration of contact between a vascular loop formed by the AICA and the eighth cranial nerve on MRI scans should be considered a normal anatomic finding and should not, on its own, be used to support the diagnosis of a "vascular compression syndrome."

No abstract