Rasmussen’s encephalitis: A case report

Rasmussen’s encephalitis (RE) is a rare neurological disorder of inflammatory aetiology characterised by encephalitis, intractable seizures, hemiparesis, variable motor deficits, and dementia. It is not commonly considered in the clinical differential diagnosis of a patient with a past history of a stroke-like episode presenting with status epilepticus. It is suspected mainly in children in whom the disease is more common. Here we report a case of an adult man presenting with a common symptom of seizure caused by Rasmussen’s encephalitis.     

Functional magnetic resonance imaging study of writer’s cramp

Background Writer＇s cramp is a type of task specific idiopathic focal dystonia and has an incompletely understood pathophysiology. The present study utilized functional magnetic resonance imaging （fMRI） to investigate what type of brain activity correlates with writer＇s cramp and its physiological mechanism.Methods Ten patients with writer＇s cramp were age and gender matched with ten nealthy control suojects in a block design. Subjectswere scanned by fMRI while performing three consecutive, visually instructive, tasks with MR Vision 2000： （1） suppositional writing, （2） writing with finger and （3） writing with a pencil. Data was analysed using AFNI software for groups of patients and controls.Results The patients with writer＇s cramp showed significant activations of contralateral basal ganglion （especially the putamen）, motor cortex （primary sensorimotor cortex, supplementary motor cortex, premotor cortex） and ipsilateral cerebellar hemisphere in writing with a pencil compared with controls; whereas there was no obvious difference between patients and controls during writing with finger. Furthermore, these differences exist in the stibtractive activated maps for ＂writing with a pencil＂ minus ＂writing with finger＂ of patients, when the activation of subcortical area and insula in controls disappeared.Conclusions Abnormal activations of contralateral basal ganglion, motor cortex and ipsilateral cerebellar hemisphere of the patients with writer＇s cramp suggest dysfunction of basal ganglion and subcortical-cortical loop might play a pathophysiological role in writer＇s cramp.     

Volumetric magnetic resonance imaging classification for Alzheimer’s disease based on kernel density estimation of local features

Background The classification of Alzheimer's disease (AD) from magnetic resonance imaging (MRI) has been challenged by lack of effective and reliable biomarkers due to inter-subject variability.This ar...     

Clinical application of functional magnetic resonance imaging in China

Functional magnetic resonance imaging （fMRI） has been widely used in basic research in the past decade, and more clinically in recent years. Unlike conventional MRI that demonstrates the anatomy and morphology of the brain, fMRI provides the functional information of the brain, including neuronal activation, perfusion, diffusion, metabolism, and fiber connection. Since the publication of the pioneer study by Ogawa et all in 1990, blood oxygenation level dependent （BOLD） technique has been adopted by neuroscientists and psychologists in research into the mechanisms of motion, vision, hearing, language, memory, and functions of the brain. Soon after, clinical studies with BOLD technique were conducted in some fields like surgery （surgical Dlanning）.     

Magnetic resonance imaging of Alzheimer’s disease: from diagnosis to therapeutic evaluation

Alzheimer＇s disease（AD）is a devastating late-life dementia that produces progressive loss of memory and mental faculties in elderly people.It is important to identify the earliest evidence of AD and to monitor the development of this disease for us to make positive response to its management.Magnetic resonance imaging（MRI）is powerful to image the tissue or organ without damnification.MRI can be employed to diagnose the early AD development and monitor the key biomarker development in AD.MRI may be helpful not only in diagnosing early AD,but also in evaluating its development.This article reviews the progress of MRI on the diagnosis and detection of AD,and makes comments on its therapeutic application.     

Rasmussen’s syndrome and its treatment by hemispherectomy

Rasmussen syndrome is a special disease which mainly affects one side of the cerebral himsphere and is complicated by intractable epilepsy. This disease is seldom encountered. We treated satisfactorily cases of Rasmussen syndrome with modified himspherectomy.     

Evaluation of cardiac structures and function in hypertrophic cardiomyopathy with magnetic resonance imaging

Objective：To assess the capability of magnetic resonance imaging（MRI） in evaluating the cardiac structures and function in the hypertrophic cardiomyopathy（HCM）. Methods：Fourteen healthy volunteers and eighteen cases with HCM verified by history, clinical presentation, electrocardiogram and echocardiography（ECG） were performed with MRI. The myocardial thickness of interventricular septum at the basal segment and that of posterolateral free wall of the left ventricle（LV） were measured. Some indexes for evaluating cardiac ftmction were measured using ARGUS auto-quantitative program. Results：The myocardial thickness of septum at the basal segment had significant difference between the HCM patients and the healthy volunteers. There was no significant difference between MRI and ECG in examining end-diastolic volume, ejection fraction of the LV. Conclusion：MRI can fully provide more information on the abnormalities of cardiac anatomy and function; thus, it is of great value in clinical application.     

Evaluating transcatheter arterial chemoembolization for primary hepatic cancer by magnetic resonance diffusion-weighted imaging

Hepatic cancer is associated with very high mortality and morbidity, and the world＇s highest morbidity and mortality rates for this malignant tumor are found in China. Each year, the number of people who die of hepatic cancer in China amounts for 53% of the world total. Although resection is the first-choice treatment for hepatic cancer, only 20%-30% of patients have the opportunity to undergo resection. Transcatheter arterial chemoembolization （TACE） is a typical intervention therapy. Its advantages include minimal trauma, precise efficacy,     

Preliminary evaluation of magnetic resonance fresh blood imaging for diagnosis of Budd-Chiari syndrome

Background Budd-Chiari syndrome （BCS） is a rare disease with portal hypertension caused by the blockage of the hepatic vein and/or the inferior vena cava （IVC）. Angiography is the ＂golden standard＂ for diagnosis, but it is an invasive examination. To assess the diagnostic value of a fresh blood imaging （FBI） relative to BCS, we used a magnetic resonance angiography （MRA） with an FBI sequence for a preoperative evaluation of the BCS patients in this study. Methods Fifty patients who were suspected of having BCS after they had been checked by a B-ultrasound were studied. 2D and 3D FBI were performed on a 1.5T superconductive MR scanner. Original images were rebuilt using a maximal intensity projection （MIP） method on the console. Two doctors reviewed all images before they learned of the angiography results. We then compared the diagnoses obtained from the FBI and angiography results to evaluate the diagnostic value of the FBI. Results Forty-one patients were diagnosed as BCS and 9 as non-BCS based on an angiography. The FBI correctly diagnosed 38 patients, incorrectly diagnosed 1 patient, and missed diagnosis in 3 patients. Thus, the diagnostic sensitivity of the FBI is 93% （38/41）, the specificity is 89% （8/9） and the accuracy is 92% （46/50）. The FBI images of the 13 membranous stenoses of the IVC showed a sudden stenosis of the post-liver segment of the IVC. The Images of the 5 patients with a membranous obstruction of the IVC showed IVC thickening and an absence of blood signals in the post-hepatic segment of the IVC. The images of the 4 patients with the segmental thrombosis of the IVC showed abnormal and intermittent signals in the IVC. The images of the 6 patients with a simple hepatic vein obstruction showed obstructive hepatic veins. The images of the 6 patients with the stenosis of both the IVC and the hepatic veins showed the stenosis of the IVC, the thickening of the hepatic veins and the formation of a compensatory circulation within the liver. Lastly, the images of the 7 patients showed a combination of the IVC thrombosis with stenosis or with the obstruction of one or two hepatic veins. Conclusions An FBI can show a membranous stenosis, and an obstruction and thrombosis of the IVC. In addition, it can also demonstrate the thickening of the flexural hepatic vein and the development of intra-hepatic compensatory branches with slow blood flow. Thus, it can guide the puncturing and opening of the hepatic vein involved in an interventional therapy for BCS patients.     

The research of myelinization of normal fetal brain with magnetic resonance imaging.

ＴｈｅｒｅｓｅａｒｃｈｏｆｍｙｅｌｉｎｉｚａｔｉｏｎｏｆｎｏｒｍａｌｆｅｔａｌｂｒａｉｎｗｉｔｈｍａｇｎｅｔｉｃｒｅｓｏｎａｎｃｅｉｍａｇｉｎｇＷａｎｇＺｈｏｎｇｑｉｕ王中秋，ＣｈｅｎＪｕｎｋｕｎ陈君坤，ＱｉｎＺｈｉｈｏｎｇ秦志宏ａｎｄＺｈａｎｇＪｉ...     

Dynamic contrast-enhanced magnetic resonance perfusion weighted imaging in astrocytomas： correlation with histopathology and immunohistochemistry

Objective： To investigate magnetic resonance perfusion weighted imaging and its relationship with the grading and the expression of vascular endothelial growth factor （VEGF） and angiogenesis in astrocytomas. Methods： A collection of 34 patients with astrocytomas proved by surgery and pathology were examined by magnetic resonance imaging（MRI）, with 26 cases of grade Ⅰ-Ⅱ （low-grade） and 8 cases of grade Ⅲ-Ⅳ （high-grade）. MR perfusion images were obtained with spin-echo echo planar imaging （SE-EPI） techniques. Expression of VEGF was examined by immunohistochemical method of streptavidin-biotin-peroxidase（SP）. The vascular development was measured by micro-vascular density （MVD） which was immunostained with anti-factor Ⅷ-related antigen monoclonal antibody. Results： Both of the expression of VEGF and the angiogenesis in 34 cases of astrocytomas were significantly correlated to the maximum relative cerebral blood volume （Max rCBV） （r=0.604, P〈0.001; r=0.625, P〈0.001, respectively）. The Max rCBV and the expression of VEGF, MVD in high-grade astrocytomas were significantly higher than that of in low-grade astrocytomas （t=3.0, P=0.017; t=7.08, P=0.01; t=3.37, P=0.011, respectively）. Conclusion： MR perfusion weighted imaging might be a valuable method in in vivo study of the angiogenesis of astrocytomas and evaluating their malignant degree and prognosis.     

Gender and magnetic resonance imaging classification-related differences in clinical and biochemical characteristics of Cushing＇s disease： a single-centre study

Background Cushing＇s disease （CD） presents a remarkable preponderance in female gender,and a significant minority of patients with CD presented with negative magnetic resonance imaging （MRI） findings.The aim of this study was to evaluate gender-related and MRI classification-related differences in clinical and biochemical characteristics of CD.Methods We retrospectively studied 169 patients with CD,comprising 132 females and 37 males,and 33 patients had no visible adenoma on MRI.Results We observed that male and MRI-positive patients presented with high adrenocorticotropic hormone （ACTH） values （P ＜0.05）.Female patients presented with higher prevalence of hirsutism and hyperpigmentation and lower prevalence of purple striae （P ＜0.05）.The prevalence of buffalo-hump and hypertension was greater in MRI-negative patients （P ＜0.05）.In addition,male patients with CD presented at a younger age compared with females （P ＜0.05）.Patients with fatigue and hypokalaemia presented significantly higher urinary-free cortisol,ACTH and cortisol levels compared with patients without these symptoms （P ＜0.05）.The prevalence of LH reduction,hyper total cholesterol （TC） and hyper low-density lipoprotein was more frequent in MRI-positive patients （P ＜0.05）.Hyper-TC levels and PRL reduction were more frequent in males （P ＜0.05）.T3,T4 and FT3 levels negatively correlated with age at diagnosis （r=-0.310,P ＜0.01; r=-0.191,P ＜0.05; r＝-0.216,P ＜0.05）.T3,T4,FT3 and FT4 levels significantly negatively correlated with 8-am plasma cortisol levels （r=-0.328,P ＜0.01; r=-0.195,P ＜0.05; r=-0.333,P ＜0.01; r＝-0.180,P ＜0.05）.Females presented higher total protein level （P ＜0.01） and lower blood urea nitrogen and serum creatinine levels （P ＜0.01）,compared with male patients.Conclusions Carefulness and caution are required in all patients with CD,because of the complexity of clinical and biochemical characteristics in CD patients of different gender and MRI cl     

Patients’ experience of outsourcing and care related to magnetic resonance examinations

Background. Outsourcing radiological examinations from public university hospitals affects the patient, who has to attend a different clinic or hospital for the radiological examination. We currently have a limited understanding of how patients view outsourcing and their care related to MR examinations.

Aim. To examine the experiences of patients who are sent to private radiology units when their referrals for MR examinations are outsourced from a university hospital, as well as to explore factors which influence patient satisfaction regarding the quality of care related to the MR examination.

Methods. A group of patients (n = 160) referred for MR examinations and either examined at a university hospital or at an external private unit were interviewed. The interview was designed as a verbal questionnaire. Data were analyzed using Student’s t test, analysis of variance (ANOVA), and Pearson’s correlation.

Results. Sixty-nine percent of the patients could neither choose nor influence the location at which they were examined. For those who could, aspects that influenced the patient’s choice of radiology department were: short waiting time 79% (127/160), ease of traveling to the radiology department 68% (110/160), and short distance to their home or work 58% (93/160). For 40% (60/160) of the patients, a short time in the waiting room was related to a positive experience of the MR examination.

Conclusion. If patients were informed about outsourcing and could also choose where to have their examination, key factors contributing to patient satisfaction could be met even when MR examinations are outsourced.     

Three-dimensional-fast imaging employing steady-state acquisition and T2-weighted fast spin-echo magnetic resonance sequences on visualization of cranial nerves Ⅲ-Ⅻ

Because of the small diameter and complex anatomic course of the cranial nerves except for the optic nerve, trigeminal nerve, facial nerve, and cochlear and vestibular nerve, other cranial nerves are difficult to be visualized in magnetic resonance imaging （MRI） scanning with conventional thickness （5-10 mm）. With the rapid development of MRI technology high spatial resolution, three-dimensional and two-dimensional magnetic resonance imaging technologies have been used in recent years in the observation of normal and abnormal cranial nerves, including three-dimensional constructive interference in steady state （3D CISS） sequence, three- dimensional magnetization-prepared rapid gradient-echo （3D MP-RAGE） sequence, three-dimensional fast inflow with steady-state precession （3D FISP） seohuence, and some fast spin-echo （FSE） sequences. - Threedimensional fast imaging employing steady-state acquisition （3D-FIESTA） is a fast three-dimensional steady-state imaging sequence with high spatial resolution and contrast between the organizational structures. And this sequence was reportedly used in the study on the diseases in the cerebellopontine angle; inner ear and posterior fossa tumors.7＇8 However, the reports about the value of 3D-FIESTA sequence for the visualization of normal cranial nerves are still rare.     

SPIO-enhanced magnetic resonance imaging for differentiating metastatic from hyperplastic lymph nodes： A study in rabbits

To investigate the potential of superparamagnetic iron oxide particles (SPIO) in MR imaging for the differentiation between hyperplastic and metastatic lymph node. Methods: Animal models of malignant lymph node metastasis were established in 6 New-Zealand rabbits by a unilateral intra-muscular injection of VX2 carcinoma cells,and models of hyperplastic lymph nodes were induced in another 6 rabbits by a unilateral intra-muscular injection of egg yolk emulsion. MR images of the lymph nodes were obtained before and 12 h after interstitial injection of SPIO. Image results were analyzed and compared with pathological findings. Results: On unenhanced images, the signal intensity of hyperplastic and metastatic lymph nodes did not differ significantly. After administration of SPIO, the signal intensity of beth hyperplastic and metastatic lymph nodes remained unchanged on T1-weighted SE images. On T2-weighted SE ima-ges, the signal intensity of hyperplastic lymph nodes decreased heterogeneously, while that of all metastatic ones re-mained unchanged. On T2-weighted GRE images, the signal intensity of hyperplastic lymph nodes decreased signifi-cantly and homogeneously, while that of 4 metastatic ones remained unchanged and that of the rest 2 decreased hetero-geneously. Conclusion: SPIO-enhanced MR imaging may enable the differentiation between the hyperplastic and meta-static lymph nodes.     

Magnetic resonance imaging on complications of breast augmentation with injected hydrophilic polyacrylamide gel

The injection augmentation mammaplasty for cosmetic purpose has been popular recently in China. Two kinds of injectable material are used clinically, autologous fat and biomaterial. The fat injection for breast augmentation is in question with the major problems of progressive fat re-absorption, microcalcification, and fat liquefaction. Now, the principal alloplastic biomaterial for injection augmentation mammaplasty in China is hydrophilic polyacrylamide gel （HPAAG）. Although thousands of breasts have been augmented with HPAAG and it seems to be a good biocompatible material, some complications develop after HPAAG injection augmentation mammaplasty.The patients had to undergo surgery to remove the injected HPAAG and associated lesions. Ultrasonography or magnetic resonance imaging （MRI） should be taken preoperatively to demonstrate the distribution of injected HPAAG and associated lesions. In this report, the diagnostic value and clinical significance of MRI on the complications of HPAAG breast augmentation were discussed.     

Others—— Role of dynamic magnetic resonance imaging in the diagnosis of female stress urinary incontinence

Objective To evaluate the application of dynamic magnetic resonance imaging in the diagnosis stress urinary incontinence （ SUI ） Methods magnetic resonance imaging of female Dynamic （DMRI） were performed on 30 healthy female volunteers and 35 female SUI patients DMRI of the pelvic floor at rest and on maximal strain were performed by using sagittal T2-weighted fast gradi ent sequences. The distance of Urethra-vesical junction to and angle of inclination at rest and on maximal of the urethral strain position axis were measured The t-value exact test were used to analyze the data.     

Initial experience with circumferential pulmonary vein ablation guided by fusion of magnetic resonance imaging with three-dimensional electroanatomic mapping

Catheter ablation for the treatment of atrial fibrillation （AF） has been a focal target ofelectrophysiological study in recent years. Up to date, circumferential pulmonary vein ablation （CPVA） guided by three-dimensional （3-D） electreanatomic mapping （Carto, USA） has been one of the most favourable procedures for the treatment of AF. However, it is still difficult to acquire the detailed information on number, location, and branching pattern of all pulmonary veins （PVs） when the 3-D electroanatomic mapping system is used alone.