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3 T MRI and (1)H MRS were useful for quantitative investigation of the serial development of hepatobiliary changes in Opisthorchis viverrini infection in hamsters, and the differential diagnosis of cholangiocacinoma (CCA) development from bile duct changes and normal condition is unclear. In this study, we investigated the serial development of hepatobiliary changes and CCAgenesis in O. viverrini-infected and N-nitrosodimethylamine (NDMA) treated hamsters (ON group) using 3 T MRI and (1)H MRS and the results were compared with those either in the O. viverrini-infected group (OV group) and uninfected normal controls. In the ON group, CCAs were first found at 9 weeks post-infection, with sizes of ~2 mm. The typical MR signal characteristics of CCA were hypo- and occasionally isointensity signal on T1-weighted images, and mild-moderate to hyper-intensity signal on T2-weighted images compared to the liver parenchyma. T2-weighted images with fat suppression revealed dilatation of the intra- and extrahepatic bile ducts, and often defined the anatomical level of biliary obstruction, cystic lesions, liver abscesses, and CCA which was starting seen of these noticeable abnormalities at 5 weeks onwards. The results of fibrosis grading using MR images showed a positive correlation (r=0.90, P<0.038 by Spearman's rank correlation test) with those of the histopathological grading. In addition, 3.0 T (1)H MRS showed elevated choline and decreased lipids levels in the liver tissues of the ON group. In conclusion, MRI and (1)H MRS are useful for the quantitative investigation of the serial development of hepatobilary changes and CCA in hamsters, and are potentially useful as early diagnostic tools for CCA., (Copyright © 2015 Elsevier Inc. All rights reserved.)

A 3T MR scanner was used to investigate the relationship between the alteration of bile duct lesions and the hepatic metabolic changes in hamsters infected with Opisthorchis viverrini by using 3T MRI and (1)H MR spectroscopy. Animals were divided into control and infected groups. Five normal hamsters were used as control; fifty-five hamsters were infected with O. viverrini to induce bile duct lesions and hepatic metabolic changes. T2-weighted image sequence in three orthogonal planes were conducted by MRI scans. Single-voxel (1)H MRS was performed to obtain the relative choline-to-lipid ratios. The livers and bile ducts were excised for the histologic examination. The progression of bile duct changes by histology and metabolic changes in O. viverrini infected hamsters were co-investigated. In the O. viverrini-infected group, the T2-weighted images revealed the time-dependent intra- and extra-hepatic duct dilatations in the liver. The mean (±SD) choline-to-lipid ratios were 0.11±0.035 in the control group, whereas the ratio in the infected group increased significantly with the progression of time. Histologic grading of hepatic inflammation and fibrosis were correlated well with the MRI grading (Spearman rank correlation test; r=0.746 and p<0.001). The control group showed no dilatation of the bile ducts and showed normal liver patterns. Noninvasive technique, MRI and (1)H MRS can demonstrated and applied to evaluate not only the inflammation-related fibrosis in the small bile ducts but also the metabolic changes in the liver induced by O. viverrini infection. A significant increase in the choline-to-lipids ratios were observed in parallel with the time-course of infection. O. viverrini infected in human is detected by stool examination. Hepatobiliary morbidity is detected and followed up by ultrasonography. MRI and MRS can be used in conjunction with ultrasonography for evaluation of progression of the disease., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Objective: To evaluate the diagnostic value of clinical findings, electromyography and magnetic resonance imaging of root lesions in traumatic brachial plexus injuries, Material and Method: The authors clinically evaluated 175 cervical roots (C5-8, T1) in patients with traumatic brachial plexus injuries then with electromyography and magnetic resonance imaging (MRI). Each finding, taken alone and in combination with each other, was compared with the findings of exploratory surgery., Results: The mean correlations of the clinical findings, electromyography and MRI in relation to the surgical findings were 60, 87 and 70 percent, respectively. The mean correlation was highest (90%) when the positive findings from the clinical, electromyographic or MRI investigations were combined. The correlation of the C5-6 root injuries was improved to 100% though the mean correlation was only 90%., Conclusion: The combination of clinical findings and electromyography correlated well with the surgical findings of root lesions caused by traumatic brachial plexus injury. MRI markedly improved identification only of C5-6 root injuries.

Eosinophilic meningoencephalitis is prevalent and widely distributed in Thailand, especially in the northeastern and central parts of the country. Angiostrongylus cantonensis is one of the causative agents of fatal eosinophilic meningoencephalitis. The nematodes produce extensive tissue damage by moving through the brain and inducing an inflammatory reaction. We report the clinical features and the findings revealed by MR imaging and MR spectroscopy in six patients with eosinophilic meningoencephalitis. The clinical presentation included severe headache, clouded consciousness, and meningeal irritation. Abnormal findings on MR images included prominence of the Virchow-Robin spaces, subcortical enhancing lesions, and abnormal high T2 signal lesions in the periventricular regions. Proton brain MR spectroscopy was performed in three patients and was abnormal in one severe case, showing decreased choline in a lesion. Small hemorrhagic tracts were found in one case. Lesions thought to be due to microcavities and migratory tracts were found in only one case. We believe the MR imaging and MR spectroscopy findings are of diagnostic value and helpful in understanding the pathogenetic mechanisms of the disease.