Transient hepatic intensity differences: part 1, Those associated with focal lesions.

OBJECTIVE: The purpose of our study was to evaluate, on MRI, transient hepatic signal intensity differences (THID) that have already been seen on CT as transient hepatic attenuation differences (THAD) and to show the range of appearance of such arterial phenomena, when associated with focal lesions, in an effort to correlate morphology, cause, and pathogenesis. CONCLUSION: Hepatic arterial phenomena visualized on MRI should be known and recognized to avoid incorrect diagnoses and to improve the characterization of focal liver lesions because their shape can lead to an understanding of pathogenetic mechanisms.