The Value Of Gd-EOB-DTPA For The MR Diagnosis And Differential Diagnosis In Focal Liver Lesions

Objective To investigate the efficacy of gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid(Gd-EOB-DTPA) in the detection and the characterization of focal liver lesions.Material and methods fifty patients known to have or suspected of having hepatic lesions underwent magnetic resonance (MR) imaging with Gd-EOB-DTPA . All patients had a biphasic contrast-enhanced spiral computed tomography (CT) or ultrasonography (US) as a standard of reference (SOR) within a time-frame of 1 months before or after the MRI examination; and all patients had physical examinations and laboratory examination prior and post the magnetic resonance (MR) imaging with Gd-EOB-DTPA. 8 patients were present by histopathology or biopsy, 42 patients were present by clinical study or imaging follow-up. MR examination consisted of precontrast GRE T1- weighted (w) and T2-w sequences, T1-w dynamic sequences after bolusinjection of 0.025 mmol .T1-w sequences with fat saturation in the hepatocyte-phase after 10,15and 20 minutes. To compare the enhancement patten and the characterization of focal liver lesions . Quantitative analyses were performed by measuring contrast-to-noise ratios (CNRs) and percentage of reinforcement and the detection of focal liver lesions on pre- and postcontrast MR imagine using Gd-EOB-DTPA. Statistical significance was assumed at p< 0.05.Result do t-test of the detection of the lesions for prior and post MR-enhancement and post CT-enhancement, for small leions(Φ≤1cm),there is more sensitivity of post MR-enhancement compared with prior MR-enhancement and post CT-enhancement(p<0.0025). for lesions between 1cm and 3cm(1cm<Φ≤3cm), there is no significant difference between prior and post MR-enhancement(p>0.05), but there is significant difference between post MR-enhancement and post CT-enhancement(p<0.025).for large lesions(Φ>3cm),there is no significant difference between the three exam methods(p>0.05).MR-enhancement after bolus injection Gd-EOB-DTPA, in the dynamic-phase, there are typical enhancement pattern for hepatocellular carcinoma, liver metastasis, focal nodal hyperplasia and hemangioma. Do the SNK-test in percentage of reinforcement , slope rate of arterial phase of time-reinforcement curve and contrast-to-noise ratios (CNRs), comparing the three type of lesions, there is significant difference between the three type of lesions'percentage of arterial phase reinforcement , slope rate of time-reinforcement curve(p<0.001), to the percentage of hepatocyte-phase reinforcement in 10 min, FNH has a significant difference compared to HCC and liver metastasis(p<0.001). there is no significant difference between HCC and liver metastasis(p>0.05).for the hepatocyte-phase CNR of the three type of lesions in 10 min, there is also a significant difference(p<0.001) between FNH and HCC,liver metastasis. there is no significant difference between HCC and liver metastasis(p>0.05).Conclusion varies of focal liver lesions have different characterizations in dynamic sequences imagines after bolusinjection of Gd-EOB-DTPA, there is a high development of detection for small lesions in the hepatocyte-phase. Combine the dynamic sequences and hepatocyte-phase will be more helpful to the qualitative analysis between benign and malignant tumors ,then to improve the accurate and authenticity of the diagnose.