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Characterization of focal liver lesions with superparamagnetic iron oxide-enhanced MR imaging: value of distributional phase T1-weighted imaging.

Lee JM, Kim CS, Youk JH, Lee MS - Korean J Radiol (2003 Jan-Mar)

Bottom Line: Postcontrast T1-weighted imaging was performed within eight minutes of infusion of the contrast medium (distributional phase).Both qualitative and quantitative analysis was performed.T1-weighted double-echo FLASH images obtained soon after the infusion of ferumoxides, show characteristic enhancement patterns and improved the differentiation of focal liver lesions.

View Article: PubMed Central - PubMed

Affiliation: Department of Diagnostic Radiology, Seoul National University Hospital, Korea. leejm@radcom.snu.ac.kr

ABSTRACT

Objective: To determine the potential value of distributional-phase T1-weighted ferumoxides-enhanced magnetic resonance (MR) imaging for tissue characterization of focal liver lesions.

Materials and methods: Ferumoxides-enhanced MR imaging was performed using a 1.5-T system in 46 patients referred for evaluation of known or suspected hepatic malignancies. Seventy-three focal liver lesions (30 hepatocellular carcinomas (HCC), 12 metastases, 15 cysts, 13 hemangiomas, and three cholangiocarcinomas) were evaluated. MR imaging included T1-weighted double-echo gradient-echo (TR/TE: 150/4.2 and 2.1 msec), T2*-weighted gradient-echo (TR/TE: 180/12 msec), and T2-weighted turbo spin-echo MR imaging at 1.5 T before and after intravenous administration of ferumoxides (15 mmol/kg body weight). Postcontrast T1-weighted imaging was performed within eight minutes of infusion of the contrast medium (distributional phase). Both qualitative and quantitative analysis was performed.

Results: During the distributional phase after infusion of ferumoxides, unique enhancement patterns of focal liver lesions were observed for hemangiomas, metastases, and hepatocellular carcinomas. On T1-weighted GRE images obtained during the distributional phase, hemangiomas showed a typical positive enhancement pattern of increased signal; metastases showed ring enhancement; and hepatocellar carcinomas showed slight enhancement. Quantitatively, the signal-to-noise ratio of hemangiomas was much higher than that of other tumors (p <.05) and was similar to that of intrahepatic vessels. This finding permitted more effective differentiation between hemangiomas and other malignant tumors.

Conclusion: T1-weighted double-echo FLASH images obtained soon after the infusion of ferumoxides, show characteristic enhancement patterns and improved the differentiation of focal liver lesions.

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Related in: MedlinePlus

Liver hemangioma in a 67-year-old woman.A. Precontrast T1-weighted in-phase gradient-echo image depicts a round hypointense lesion (arrow) in the right lobe of the liver.B. Precontrast T2-weighted turbo spin-echo image shows a hyperintense lesion (arrow) in the liver.C. Ferumoxides-enhanced T1-weighted in-phase gradient-echo image obtained during the distributional phase demonstrates positive enhancement of the lesion (arrow), similar to that of the intrahepatic portal vein (open arrow). Note positive enhancement of the abdominal aorta (arrowhead).D. Ferumoxides-enhanced T2-weighted turbo-spin echo image shows reduced intensity of the lesion (arrow) compared to precontrast image (A).
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Figure 1: Liver hemangioma in a 67-year-old woman.A. Precontrast T1-weighted in-phase gradient-echo image depicts a round hypointense lesion (arrow) in the right lobe of the liver.B. Precontrast T2-weighted turbo spin-echo image shows a hyperintense lesion (arrow) in the liver.C. Ferumoxides-enhanced T1-weighted in-phase gradient-echo image obtained during the distributional phase demonstrates positive enhancement of the lesion (arrow), similar to that of the intrahepatic portal vein (open arrow). Note positive enhancement of the abdominal aorta (arrowhead).D. Ferumoxides-enhanced T2-weighted turbo-spin echo image shows reduced intensity of the lesion (arrow) compared to precontrast image (A).

Mentions: For each type of lesion, ferumoxides-enhanced T1-weighted double-echo GRE images obtained during the distributional phase demonstrated some degree of characteristic enhancement. All 13 hemangiomas showed positive enhancement at T1-weighted in- and out-of-phase GRE imaging (Fig. 1). Intrahepatic vessels were also hyperintense to the liver, with a degree of intensity similar to that demonstrated by hemangiomas. In all of these, a slight degree of signal intensity drop was noted, though for metastatic tumors, HCCs and cysts, this was not the case. Ferumoxides-enhanced T1-weighted double-echo imaging revealed no enhancement of cystic lesions, though at distributional-phase T1-weighted in- and out-of-phase imaging, peripheral rim enhancement was seen in nine metastases (75%) and two of three cholangiocarcinomas (67%) (Figs. 2, 3). In addition, T1-weighted dual-echo imaging of HCCs revealed slight enhancement in 24 lesions (80%), ring enhancement in two (6.7%), and no noticeable enhancement in four (13.3%).


Characterization of focal liver lesions with superparamagnetic iron oxide-enhanced MR imaging: value of distributional phase T1-weighted imaging.

Lee JM, Kim CS, Youk JH, Lee MS - Korean J Radiol (2003 Jan-Mar)

Liver hemangioma in a 67-year-old woman.A. Precontrast T1-weighted in-phase gradient-echo image depicts a round hypointense lesion (arrow) in the right lobe of the liver.B. Precontrast T2-weighted turbo spin-echo image shows a hyperintense lesion (arrow) in the liver.C. Ferumoxides-enhanced T1-weighted in-phase gradient-echo image obtained during the distributional phase demonstrates positive enhancement of the lesion (arrow), similar to that of the intrahepatic portal vein (open arrow). Note positive enhancement of the abdominal aorta (arrowhead).D. Ferumoxides-enhanced T2-weighted turbo-spin echo image shows reduced intensity of the lesion (arrow) compared to precontrast image (A).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2698062&req=5

Figure 1: Liver hemangioma in a 67-year-old woman.A. Precontrast T1-weighted in-phase gradient-echo image depicts a round hypointense lesion (arrow) in the right lobe of the liver.B. Precontrast T2-weighted turbo spin-echo image shows a hyperintense lesion (arrow) in the liver.C. Ferumoxides-enhanced T1-weighted in-phase gradient-echo image obtained during the distributional phase demonstrates positive enhancement of the lesion (arrow), similar to that of the intrahepatic portal vein (open arrow). Note positive enhancement of the abdominal aorta (arrowhead).D. Ferumoxides-enhanced T2-weighted turbo-spin echo image shows reduced intensity of the lesion (arrow) compared to precontrast image (A).
Mentions: For each type of lesion, ferumoxides-enhanced T1-weighted double-echo GRE images obtained during the distributional phase demonstrated some degree of characteristic enhancement. All 13 hemangiomas showed positive enhancement at T1-weighted in- and out-of-phase GRE imaging (Fig. 1). Intrahepatic vessels were also hyperintense to the liver, with a degree of intensity similar to that demonstrated by hemangiomas. In all of these, a slight degree of signal intensity drop was noted, though for metastatic tumors, HCCs and cysts, this was not the case. Ferumoxides-enhanced T1-weighted double-echo imaging revealed no enhancement of cystic lesions, though at distributional-phase T1-weighted in- and out-of-phase imaging, peripheral rim enhancement was seen in nine metastases (75%) and two of three cholangiocarcinomas (67%) (Figs. 2, 3). In addition, T1-weighted dual-echo imaging of HCCs revealed slight enhancement in 24 lesions (80%), ring enhancement in two (6.7%), and no noticeable enhancement in four (13.3%).

Bottom Line: Postcontrast T1-weighted imaging was performed within eight minutes of infusion of the contrast medium (distributional phase).Both qualitative and quantitative analysis was performed.T1-weighted double-echo FLASH images obtained soon after the infusion of ferumoxides, show characteristic enhancement patterns and improved the differentiation of focal liver lesions.

View Article: PubMed Central - PubMed

Affiliation: Department of Diagnostic Radiology, Seoul National University Hospital, Korea. leejm@radcom.snu.ac.kr

ABSTRACT

Objective: To determine the potential value of distributional-phase T1-weighted ferumoxides-enhanced magnetic resonance (MR) imaging for tissue characterization of focal liver lesions.

Materials and methods: Ferumoxides-enhanced MR imaging was performed using a 1.5-T system in 46 patients referred for evaluation of known or suspected hepatic malignancies. Seventy-three focal liver lesions (30 hepatocellular carcinomas (HCC), 12 metastases, 15 cysts, 13 hemangiomas, and three cholangiocarcinomas) were evaluated. MR imaging included T1-weighted double-echo gradient-echo (TR/TE: 150/4.2 and 2.1 msec), T2*-weighted gradient-echo (TR/TE: 180/12 msec), and T2-weighted turbo spin-echo MR imaging at 1.5 T before and after intravenous administration of ferumoxides (15 mmol/kg body weight). Postcontrast T1-weighted imaging was performed within eight minutes of infusion of the contrast medium (distributional phase). Both qualitative and quantitative analysis was performed.

Results: During the distributional phase after infusion of ferumoxides, unique enhancement patterns of focal liver lesions were observed for hemangiomas, metastases, and hepatocellular carcinomas. On T1-weighted GRE images obtained during the distributional phase, hemangiomas showed a typical positive enhancement pattern of increased signal; metastases showed ring enhancement; and hepatocellar carcinomas showed slight enhancement. Quantitatively, the signal-to-noise ratio of hemangiomas was much higher than that of other tumors (p <.05) and was similar to that of intrahepatic vessels. This finding permitted more effective differentiation between hemangiomas and other malignant tumors.

Conclusion: T1-weighted double-echo FLASH images obtained soon after the infusion of ferumoxides, show characteristic enhancement patterns and improved the differentiation of focal liver lesions.

Show MeSH
Related in: MedlinePlus