Functional MR Imaging In Liver Cirrhosis

Part 1 The cilinical research of 1.5T 1H-MRS in human liverMR spectroscopy is a method of functional MR imaging. It enables the noninvasive measurement of biochemical information and metabolic changes in vivo. In vivo, MRS has been successfully in the diagnosis of tumor in the brain, prostate, and breast. To date, MRS including 1H-MRS and 31P-MRS has been proved useful in liver. Early researches focused on in vitro study and ainimal experiments, and the method generally used is 31P-MRS. Dring this period, the researcher found that: the main detectable metabolites are PME,PDE,ATP,α- ATP,β-ATP, and inorganic phosphate; the peak area and height of a metabolite signal is directly related to its conceration ; it can be used to differentiating malifnant lesions from benign lesions in ainimal research. 1H-MRS was also applied a lot on in vitro study and ainimal experiments, and found 4 peaks in vivo: glycogen, choline, glutamine and glutamate complex, lipide.As technique advanced, 1H-MRS in liver has developed to in vivo and cinical application. The results and main findings include: 1H-MRS is a useful method in diagnosis of liver steatosis and a significant relationship between histological degree of steatosis and lipid contents at 1H-MRS examination was found; it can differentiating malifnant lesions from benign lesions; the relationship between 1H-MRS examination and liver cirrhosis/fibrosis was primarily established. Our research is to study the 1.5T 1H MR spectrum of human liver, investigate the the difference between normal people and hepatocirrhosis, and find a new non-invasive method to diagnose and stage liver cirrhosis.Conclusion:1. 1H-MRS is an effective method, the success rate in our stuy is 91.9%.2. In vivo four peaks in human liver were detected by proton MR spectroscopy, but not appeared in all the people.3. The metabolitic peaks varied among different age and gender.4. The Cho and Glx value of liver cirrhosis group was higher than the control group and was positive correlated with child stage.5. The Glx value is more sensitive than Cho value in early diagnosis of liver cirrhosis, but the Cho value is more accurate in stage it. MR-DTI is a useful tool for early diagnosis and evaluating the severity of liver fibrosis. Single-voxel 1.5T 1H MR spectrum for normal human liver among different age and genderPurpose To study the single-voxel 1H MR spectrum of normal human liver and to endeavor to have an initial understanding of the distinction of the concentration and distribution of main metabolites in different age and sex.Methods Fifty health human livers were examined by GE Propell HD 1.5T MRI system in Prob-P.Results In vivo a variety of metabolites in human liver were detected by proton MR spectroscopy. The main detectable metabolites were lipide (Lip: at 1.3ppm) , glutamine and glutamate complex (Glx: at 3.35～3.9ppm), choline (Cho:at 3.2ppm) and glycogen (Glyu: at 2.10～2.49ppm). The metabolite concentration varied among different age and gender. The signal intensity calculation showed that: cho was negative correlated with age and there was no marked difference among genders. The glyu,glx and lip were variant significantly between different gender. The glx and lip were positive correlated with age. The glyu showed no marked difference among different age.Conclusions A number of chemical compounds pertaining to metabolism in liver can be measured with 1H-MRS quantitatively. It is useful to assess the hepatic biochemical changes both in healthy subjects and in patients, and provid evidence to early diagnosis. In vivo, 1.5T 1H MR spectroscopic assessment of liver cirrhosisPurpose To study the 1.5T 1H MR spectrum of patients with liver cirrhosis, investigate the feasibility of qualitatively detecting hepatocirrhosis and find a new non-invasive method to diagnose and stage liver cirrhosis.Methods Sixteen patients with child A liver fibrosis( mean age =33.5±10.3years, 13males and 3 females),9 child B(mean age =39.3±11.3years, 4males and 5females ) and 6 child C(mean age =48.2±8.9years,2males and 4females ) were included. All patients had clinical data and serum makers in full. Fifty normal controls (mean age =35.2±14.2, 28males and 22 females) were also included. They were examined by GE Propell HD 1.5T MRI system in Prob-P.Results A significant statistical difference was observed between control vs. liver cirrhosis in choline and glutamine/glutamate (P=0.013 and P=0.000), whereas no significant statistical difference was observed in lipid and glycogen. Among different child groups, a significantly statistical difference was observed between A vs. B,B vs. C and A vs. C in choline (P=0.000 , P=0.000 and P=0.000),however,a statistically significant difference in glutamine/glutamate was achieved only betweenm A and C stage of the disease(P=0.003).Conclusions 1.5T 1H-MRS successfully differentiates child A,B and C stages of liver cirrhosis and could be a powerful non-invasive diagnostic method in liver cirrhosis. Part 2 Value of Magnetic resonance diffusion tensor imaging for liver cirrhosisObjective To find the relation between Magnetic resonance diffusion tensor imaging (MR-DTI) and severity of liver fibrosis, and study the value of MR-DTI in evaluating the severity of liver fibrosis.Materials and methods: Seventeen patients with child A liver fibrosis( mean age =35.0±11.8years, 14males and 3 females),12 child B(mean age =44.7±14.0years, 5males and 7females) and 8 child C(mean age =48.7±7.6years,3males and 5females ) were recruited. All patients had clinical data and serum makers in full. Fifty normal controls (mean age =35.2±14.2, 28males and 22 females) were also recruited. Diffusion tensor imaging (DTI) was acquired using a GE Propeller HD 1.5T MR scanner by employing a spin echo single-shot EPI sequence .Average diffusion coefficient (ADC) and FA maps were generated from each participant's DTI scan using AW4.2 software. Statistical comparisons were performed using one-way ANOVA among child A group, child B group and child C group. A P value of less than 0.05 after multiple comparisons was deemed to be significant. The analysis was performed among the control group and the liver fibrosis group using two sample t-test and a P value of less than 0. 05 was deemed to be significant. All the statistic analysis was performed in SPSS11.0.Results The analysis showed significantly low ADC and changed FA in liver fibrosis group (P < 0. 05) . With the development of liver fibrosis, the ADC values were 1.33±0.18,1.02±0.12,0.66±0.27 for child A, B, C respectively, the FA values were 0.42±0.08, 0.56±0.05,0.71±0.04 for child A, B, C respectively and significant differences were be found among them.Conclusions: MR-DTI is relevant to the severity of liver fibrosis, and may be a useful tool for evaluating the severity of liver fibrosis. Part 3 Comparison of MRS with MR-DTI on Cl inical Assessment in Patients with Liver CirrhosisObjective To measure and to compare the value in diagnosing and staging liver cirrhosis between MRS and MR-DTI.Methods The magnetic resonance imaging materials of 87 MR-DTI examinees and 81 MRS examinees were analyzed. The measured values were calculated and compared with receiver operating characteristic (ROC) curves.Results The areas under the ROC curves (AUC) of FA,ADC,cho and glx were all larger than 0.5 and p<0.05, the AUC between MRS and DTI were significant different(DTI>MRS);the ADC values were significant different among control group ,child A group, child B group and child C group, other measured values were no significant different between the control group and ,child A group.Conclusion Both MRS and MR-DTI have good evaluation effect in liver cirrhosis. However, the effect of DTI was much better than that of DTI.