Study On Changes Of MRI Performance Of Different Clinical Stages Of Hepatocirrhosis Proved By Pathology

Objective1 .To compare and to evaluate the efficiencies of four kinds of MRI T2WI fast scanning sequences (true-FISP, IR-HASTE, TSE, and SE-EPI), and the efficiencies of two kinds of T1WI fast scanning sequences (FLASH, turbo-FLASH) in determining hepatocirrhosis.2. Study the MRI performance of hepatocirrhosis proved by pathology correlated with different grade of Child - pugh and evaluate the MRI diagnostic value.Materials and Methods1. 35 cases of hepatocirrhosis (including 12 cases of hepatic regenerative nodules) were undergone with the four T2WI sequences. 32 cases (including 11 cases of hepatic regenerative nodules) were undergone with the three T1WI sequences. MR imaging was performed with a 1.5-T MR imager and body-array coil.A section thickness of 0.8-1.0cm and a gap of 1.2-2.0 mm in all cases.All images were obtained with a matrix of 128×128, 131×256, 150×256, 160×256, 176×256, 179×256,respectively. MR scan with axial sections was conducted in every case and coronal was added when necessary. All images were classified qualitatively and quantitatively. Signal intensities of liver lesions and surrounding hepatic parenchyma, background noise standard deviations were measured respectively. Then SNRs and CNRs of these sequences were calculated and compared. Four aspects of image qualities in lesion-liver contrast,construction of focal lesions, artifacts, and organ anatomy (mainly focused on the visualization of intraliver vessels) were used in analyzing the differences of the four sequences' image quality.2. To analyze MR imagings in 53 patients proved by liver biopsies and surgically pathology with hepatocirrhosis correlated with different Child - pugh stages.Thichness,gap,matrix and way of scan of MRI were chosen the same as up.FLASH T1WI and True-FISP high-weighted T2WI and TSE T2WI FLASH T1WI after contrast enhanced were obtained also in all 53 patients.Coronal sections performed necessarily in part of them. The diagnosis of hepatocirrhosis were determined according to Diagnosis Criteria of Chronic Hepatitis China 1995.The grades of hepatocirrhosis were determined according to Child - pugh amending Criteria.The features of hepatocirrhosis in MR imagings had been analyzed,including the liver physical volume,liver surface contours.the liver parenchyma change,the gall bladder change,the spleen change,blood vessel inside the liver , bile duct changes and the portal vein changes, including with or without the ascites formation.The data were compared with the Child - pugh grades, combined the factors such as ages in the statistical analysis system.Results1. Compared with IR-HASTE and EPI, the SNR values of True-fisp and TSE are higher with statistical significance(P<0.05, respectively). However, no significance was found in SNR value between EPI and IR-HASTE (P>0.05,respectively).The CNRs of TSE were significantly higher than that of IR-HASTE (P<0.05, respectively). No significant difference in CNR was detected between IR-HASTE and EPI(P>0.05, respectively).In detecting focal lesion construction and artifacts, Significance was found among the four sequences(P<0.05, respectively). TSE was the best one among the sequences being evaluated.2. Compared with FLASH and Turbo-FLASH's SNR,value was lower significantly (P<0.05, respectively).The FLASH'S CNRs value were higher than Turbo-FLASH's.But no significant difference was found in CNR between FLASH and Turbo-FLASH(P>0.05, respectively).No significance was found between FLASH and Turbo-FLASH on lesion-liver contrast, artifact, lesion construction and organ anatomy(P>0.05, respectively).3. 43 cases included Child A stage group (14 cases), Child B stage group (16 cases), Child C stage group (13 cases).And compared group (11 cases) was added.There is close correlation between the grades of hepatocirrhosis and some parameters of liver such as liver physical volume,liver surface circumstance,bladder and spleen physical volume,etc.The change of the size of the left and right lobe of the liver and the spleen, hepatic surface contours, collaterals of portal vein all increased as the severity of hepatocirrhosis enhanced, which were of statistical significance. A little of hepatic regenerative nodules(HRN) or the thin net- or thick net-like changes can be found in liver parenchyma in the early cirrhosis group.But there is no of statistical significance^=0.053, 0.062).The performance is quite different between benign and malign HRNs.Benign nodules shows no enhancement,as malign ones shows "quick in and quick out" signs.Conclusions1 .TSE is the best sequence used in T2WI fast scanning sequence up-date because of superior quality of images and high detection rate. So, TSE should be used as the base sequence in diagnosing hepatocirrhosis. ER.-HASTE can distinct specifically the component of lesions, which be helpful to the correct diagnosis, but the inferior quality of images limits its clinic usage. 3D DCE MRP under the True-FISP sequence has big usage in the aspects of observing the vascular variety and its side of the portal vein afferently.SE-EPI is the fastest scan sequence nowadays. But its limit of more artifacts and inferior quality of images decrease wide clinic application.2. Compared with Turbo-FLASH, FLASH is the higher quality sequence of regular fast T1WI, and is the base sequence in determination of hepatocirrhosis.Although it has much lower contrast,Turbo-FLASH can be applied to some uncooperated patients for its ultrafast scan.Aim at the different patient, vivid choose should be used.3.Decreasing of the left/right liver physical volume,cnhanges of the liver surface contours,elargement of the gall bladder nest and inceasing of the spleen physical volume have statistical significance with the aggravation of hepatocirrhosis. The occurrence of HRNs and the thin net- or thick net-like changes in liver parenchyma also has statistical significance. Both reflect dynamic process of hepatocirrhosis and aggravation of liver. Routine MRI examination has limited values in diagnosis of early cirrhosis. The thin net- or thick net-like changes when enhenced in parenchyma period is a characteristic sign for early cirrhosis. MRI imagings also have big values in differentiating benign noduls from malignant ones in liver.