Dynamic MR imaging of the liver with Gd-DTPA: initial clinical results.
Gd-DTPA was evaluated as a hepatic contrast agent for MR imaging. Twenty-six consecutive patients referred for suspected masses in the liver were studied at 1.5 T. Fourteen patients had hepatic metastases and one patient each had cholangiocarcinoma and multicentric hepatocellular carcinoma. Four patients had cavernous hemangiomas and the remainder had other benign lesions. Diagnoses were proved by biopsy, sonography, or radionuclide scintigraphy in 23 cases and by autopsy in one case. Precontrast scans were obtained by using standard pulse sequences. In addition, breath-hold scans were obtained before and after bolus administration of 0.1 mmol/kg Gd-DTPA by using a multislice T1-weighted gradient-echo pulse sequence with an ultrashort echo time. Mean lesion-liver signal difference/noise increased by 50% (p less than .01) in the immediate postcontrast phase. In two of 26 cases, multiple additional lesions as small as 3 mm were detected after contrast administration that were not seen before contrast administration. In no case was lesion-liver contrast worsened on scans obtained immediately after administration of contrast material. However, on delayed scans, detection of lesions worsened in some cases because of equilibration of contrast material between liver and lesion. These initial clinical results suggest that enhancement with Gd-DTPA is a practical method for improving lesion-liver contrast and has the potential to improve the accuracy of MR imaging in the liver. However, optimized fast imaging techniques are required for best results.