[Diagnosis of focal liver lesions. The value of imaging systems].

Selection of the suitable modality for the detection or differential diagnosis of focal liver lesions must consider, in addition to its accuracy, such factors as on-site availability, the costs involved, and the stress to the patient. The preferred screening technique is ultrasonography which, however, has a high failure rate, in particular in the case of small lesions. In many cases computed tomography (CT) permits the correct diagnosis to be established.

[MR tomography of the liver at 1.5 tesla. The value of T1-weighted imaging with a fast multislice gradient-echo sequence during respiratory standstill].

The diagnostic value of a fast multislice gradient-echo sequence was compared with that of conventional spin-echo sequences in a prospective study of 76 patients. With the multislice gradient-echo sequence, the entire liver can be examined in less than 3 minutes since five sections can be imaged during one breath-holding period. The strongly T1-weighted gradient-echo sequence (GRE 100/5/80 degrees) yields a significantly better T1-contrast than the T1-weighted spin-echo sequence (SE 500/15) (p less than 0.

Focal nodular hyperplasia of the liver: MR findings in 35 proved cases.

MR images of 28 patients with 35 lesions of hepatic focal nodular hyperplasia were reviewed to determine the frequency of findings considered typical of this condition (isointensity on T1- and T2-weighted pulse sequences, a central hyperintense scar on T2-weighted images, and homogeneous signal intensity). Fifteen lesions were imaged at 0.6 T with T1- and T2-weighted spin-echo (SE) pulse sequences; 20 lesions were imaged at 1.

Differentiation of hepatic hemangiomas from metastases by dynamic contrast-enhanced MR imaging.

Twenty-nine patients with hepatic hemangiomas (n = 14) and hepatic metastases (n = 15) underwent magnetic resonance (MR) imaging prior to and after an intravenous bolus injection of Gd-diethylenetriamine pentaacetic acid (0.2 mmol/kg). Before contrast application, a T2-weighted spin echo sequence (SE 1,600/105) and a T1-weighted gradient echo sequence (GE 315/14/90 degrees pulse angle) were performed.