Use of gadobenate dimeglumine dynamic MRI for detection of early hepatocellular carcinoma in atypical hepatic focal lesions

Aim: Gadobenate dimeglumine (multihance) is a contrast medium which can be used not only as an extracellular contrast agent for dynamic imaging of the liver, but also as a liver specific agent for the acquisition of hepatobiliary-phase images which are more helpful in evaluation of small atypical hepatic focal lesions equal or less than 3 cm. The authors tried to evaluate multihance dynamic magnetic resonance imaging (MRI) as a new modality in early detection of hepatocellular carcinoma (HCC). Methods: Thirty cirrhotic patients with small hepatic focal lesions (less than 3 cm in diameter), detected by imaging (ultrasound and triphasic computed tomography) were subjected to dynamic MRI with multihance contrast. All patients had a liver biopsy stained with heat shock protein 70, glypican 3, and glutamine synthetase to confirm the diagnosis of HCC. Results: Eight out of 30 patients (26.6%) with atypical focal lesions proved to have HCC by histology, whereas 7 out of 8 histologically proven HCC patients (87.5%) were shown to have typical criteria on Multihance imaging. Conclusion: Multihance dynamic MRI is a promising diagnostic modality for detection of early HCC, however, future studies on large numbers of patients are warranted to precisely detect the sensitivity and specificity of this new modality.

Gadolinium Enhances Dual-energy Computed Tomography Scan of Pulmonary Artery

Objective To evaluate the feasibility of using gadopentetate dimeglumine(Gd-DTPA)for dual-energy computed tomography pulmonary angiography(CTPA).Methods Sixty-six patients were randomly divided into three groups and underwent CTPA.Group A had a turbo flash scan using an iohexol injection,Group B had a turbo flash scan using Gd-DTPA,and Group C had a dual-energy scan using Gd-DTPA.The original images of Group C were linearly blended with a blending factor of 0.5 or reconstructed at 40,50,60,70,80,90,100,and 110 keV,respectively.The groups were compared in terms of pulmonary artery CT value,image quality,and radiation dose.Results The pulmonary artery CT values were significantly higher in Group C40keV than in Groups B and C,but lower than in Group A.There was no significant difference in the image noise of Groups C40keV,B,and C.Moreover,Group A had the largest beam hardening artifacts of the superior vena cava(SVC),followed by Groups B and C.Group C40keV showed better vascular branching than the other three groups,among which Group B was superior to Group A.The subjective score of the image quality of Groups A,B,and C showed no significant difference,but the score was significantly higher in Group C40keV than in Groups A and B.The radiation dose was significantly lower in Group B than in Groups A and C.Conclusion Gd-CTPA is recommended to patients who are unsuitable for receiving an iodine-based CTPA.Furthermore,a turbo flash scan could surpass a dual-energy scan without consideration for virtual monoenergetic imaging.