Gadofosveset trisodium in the investigation of focal liver lesions in noncirrhotic liver: Early experience.
PURPOSE
To investigate enhancement of hepatic lesions with gadofosveset trisodium (Gdfos) (Ablavar) (blood pool agent) compared with the extracellular gadolinium contrast agent (EcGd) gadobutrol (Gadovist).


MATERIALS AND METHODS
The prospective study was approved by the Institutional Research Ethics Board with informed consent. Twelve patients underwent magnetic resonance imaging (MRI) with EcGd followed by MRI with Gdfos. For each agent qualitative analysis described the pattern of enhancement and quantitative analysis was performed using lesion-to-liver contrast-to-noise (CNR) ratio. Paired and unpaired Student's t-test used.


RESULTS
Twelve hemangiomas, four metastases, one cyst, two focal nodular hyperplasia (FNH), and three adenomas were found. Cyst, FNH, adenomas, and hemangiomas demonstrated the classic pattern of enhancement with both agents. Hemangiomas demonstrated retention of contrast with both agents and their CNR was not statistically different (P > 0.05). Metastases demonstrated retention of contrast on delayed phase with EcGd. Retention of contrast was not seen in metastases with Gdfos. CNR of metastases with Gdfos was statistically lower than CNR of metastases with EcGd (P = 0.005). CNR of hemangiomata and metastases on delayed phase were significantly different (P = 0.0008) with Gdfos, but similar with EcGd (P = 0.4).


CONCLUSION
Hemangiomas accumulate Gdfos on delayed phase and metastases do not, a key additional differentiating feature. Liver imaging with Gdfos may improve characterization of liver lesions.