Persistent repeated measurements by magnetic resonance spectroscopy demonstrate minimal hepatic encephalopathy: a case report.

Minimal Hepatic Encephalopathy (MHE), previously referred to as infraclinical or subclinical is a precursor in the development of clinical hepatic encephalopathy (HE). The demonstration of MHE is done through neuropsychological testing in the absence of clinical evidence of HE, patients showing only a mild cognitive impairment. Neuropsychological tests employed consist of Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and portosystemic encephalopathy (PSE) test score. Unfortunately, there are numerous occasions when the tests prove irrelevant: in the situation of inexperienced investigators, the patient's poor education, vision problems or concurring central nervous system disease, all of which may delay or deviate from the correct diagnosis.

Updates in MRI characterization of the thymus in myasthenic patients.

PURPOSE: To evaluate the imaging appearance of the thymus in the myasthenic patients by using chemical shift magnetic resonance imaging, and, to correlate the chemical shift ratio (CSR) with pathologic findings after surgical excision. MATERIALS AND METHODS: In the past year, a total of 11 myasthenic patients (4 males, 7 females; age range of 26-65 years), have been investigated by MRI centered at the thymic lodge. Our protocol included a Dual-Echo technique, T1-weighted In-phase/Opposed-phase MR images in all patients. A chemical shift ratio (CSR) was calculated by comparing the signal intensity of the thymus gland with that of the chest wall muscle for quantitative analysis. For this purpose, we have used standard region-of-interest electronic cursors at a slice level of the maximum axial surface of the thymus. We have identified two patients groups: a thymic hyperplasia group and a thymic tumoral group. RESULTS: With the decrease in the signal intensity of the thymus gland at chemical shift, the MR imaging was evident only in the hyperplasia group. The mean CSR in the hyperplasia group was considerably lower than that in the tumor group, 0,4964 ± 0,1841, compared with 1,0398 ± 0,0244. The difference in CSR between the hyperplasia and tumor groups was statistically significant (P=0,0028). CONCLUSION: MR imaging using T1-weighted In-phase/Opposed-phase images could be a useful diagnostic tool in the preoperative assessment of the thymic lodge and may help differentiate thymic hyperplasia from tumors of the thymus gland.

Magnetic resonance spectroscopy--a non-invasive method in evaluating focal and diffuse central nervous system disease.

Magnetic Resonance Spectroscopy is a non-invasive method, which can be performed following a routine Magnetic Resonance investigation within the same examination, and can provide very useful molecular information related to the metabolism and function of the normal and pathological structures of the brain. Its role is increasing in the establishment of a clear diagnosis, in both focal and diffuse central nervous system diseases, and the tendency is to replace the histopathology test, in certain cases, with similar or sometimes better diagnostic accuracy. This paper summarizes the principle, method, and main clinical applications, standing as a guide to procedure performing and results interpretation.

The thymus in myasthenic patients: correlation between mediastinal CT imaging and histopathological findings.

PURPOSE: To correlate computed tomographic (CT) appearance of the thymus with results from histologic examination of thymic tissue in myasthenic patients who underwent thymectomy. MATERIALS AND METHODS: A retrospective study, based on case series report, between January 2000 and December 2010 on 247 patients with generalized myasthenia gravis or myasthenic syndrome explored by CT using a specific protocol, in the Radiology and Medical Imaging Department of Fundeni Clinical Institute. All subjects in the study were operated and had a histologic evaluation. RESULTS: CT examinations of these 247 subjects showed remaining thymic mass, remnant of thymic tissue, fatty infiltration of the thymus and tumoral thymus or focal thymic mass. The results of histologic examination showed normal thymus, thymic lymphoid follicular hyperplasia, thymic atrophy, fatty infiltration and thymoma. CONCLUSION: It was a 100% correlation between CT examinations and intra-operative findings regarding the presents of focal thymic masses in our study. In the diagnostic of focal thymic mass, the only inter-disciplinary correlation is between radiological and macroscopic aspects. CT examination has a limited value in differential diagnosis between thymic lymphoid follicular hyperplasia and thymoma.