How Imaging Glutamate, γ‐Aminobutyric Acid,and Dopamine Can Inform the Clinical Treatment of Alcohol Dependence and Withdrawal

Neuroimaging studies have dramatically advanced our understanding of the neurochemical basis of alcohol dependence, a major public health issue. In this paper, we review the research generated from neurochemical specific imaging modalities including magnetic resonance spectroscopy, positron emission tomography, and single‐photon emission computed tomography in studies of alcohol dependence and withdrawal. We focus on studies interrogating γ‐aminobutyric acid (GABA), glutamate, and dopamine, as these are prominent neurotransmitter systems implicated in alcohol dependence. Highlighted findings include diminished dopaminergic functioning and modulation of the GABA system by tobacco smoking during alcohol withdrawal. Then, we consider how these findings impact the clinical treatment of alcohol dependence and discuss directions for future experiments to address existing gaps in the literature, for example, sex differences and smoking comorbidity. These and other considerations provide opportunities to build upon the current neurochemistry imaging literature of alcohol dependence and withdrawal, which may usher in improved therapeutic and relapse prevention strategies.     

Central nervous system lupus: Concomitant occurrence of myelopathy and cognitive dysfunction

Summary Reported are two cases of patients with central nervous system systemic lupus erythematosus (SLE) with clinical features of a myelopathy confirmed by magnetic resonance imaging (MRI). In one case, further evaluation including Single Photon Emission Computerized Tomography (SPECT) and neuropsychological testing, indicated higher cortical deficits which improved after treatment with monthly pulse intravenous cyclophosphamide. Subsequent cessation of cyclophosphamide was associated with further progression of the neurological disease in this patient.     

Altered brain activation by a false recognition task in young abstinent patients with alcohol dependence

BACKGROUND: Heavy alcohol intake induces both structural and functional changes in the central nervous system. Recent research developments converged on the idea that even in patients with alcohol dependence without apparent structural brain changes, some cognitive impairment exists, and associated functional change could be visualized by neuroimaging techniques. However, these data were from old (more than 50 years) patients using working memory and response inhibition tasks. Whether young abstinent patients show aberrant signs of brain activation is a matter of interest, specifically by the long-term memory retrieval task. METHODS: Subjects were 9 young patients with alcohol dependence with long-term abstinent (8 males and 1 female) and age- and education-matched 9 healthy controls (7 males and 2 females). We used a modified false recognition task in a functional MRI study. RESULTS: The young patients with alcohol dependence showed reduced activation in the right dorsolateral prefrontal cortex, anterior cingulate cortex (ACC), left pulvinar in the thalamus, and in the right ventral striatum, although behavioral performances and regional patterns of brain activation were similar between patients and controls. CONCLUSIONS: Long-term memory retrieval induced altered activations in prefrontal lobes, ACC, thalamus, and ventral striatum in young patients with alcohol dependence. These findings were correspondent to deficits of goal directed behavior, monitoring the erroneous responses, memory function, and drug-seeking behavior. Furthermore, these reduced activations can be considered as latent "lesions," suggesting subclinical pathology in alcoholic brains.     

Effects of Alcohol on Performance on a Distraction Task During Simulated Driving

Background:  Prior studies report that accidents involving intoxicated drivers are more likely to occur during performance of secondary tasks. We studied this phenomenon, using a dual-task paradigm, involving performance of a visual oddball (VO) task while driving in an alcohol challenge paradigm. Previous functional MRI (fMRI) studies of the VO task have shown activation in the anterior cingulate, hippocampus, and prefrontal cortex. Thus, we predicted dose-dependent decreases in activation of these areas during VO performance.
Methods:  Forty healthy social drinkers were administered 3 different doses of alcohol, individually tailored to their gender and weight. Participants performed a VO task while operating a virtual reality driving simulator in a 3T fMRI scanner.
Results:  Analysis showed a dose-dependent linear decrease in Blood Oxygen Level Dependent activation during task performance, primarily in hippocampus, anterior cingulate, and dorsolateral prefrontal areas, with the least activation occurring during the high dose. Behavioral analysis showed a dose-dependent linear increase in reaction time, with no effects associated with either correct hits or false alarms. In all dose conditions, driving speed decreased significantly after a VO stimulus. However, at the high dose this decrease was significantly less. Passenger-side line crossings significantly increased at the high dose.
Conclusions:  These results suggest that driving impairment during secondary task performance may be associated with alcohol-related effects on the above brain regions, which are involved with attentional processing/decision-making. Drivers with high blood alcohol concentrations may be less able to orient or detect novel or sudden stimuli during driving.     

Solitary Necrotic Nodules of the Liver: Histology and Diagnosis With CT and MRI

Background

A solitary necrotic nodule (SNN) of the liver is an uncommon lesion, which is different from primary and metastatic liver cancers.

Objectives

To analyze the classification, CT and MR manifestation, and the pathological basis of solitary necrotic nodule of the liver (SNN) in order to evaluate CT and MRI as a diagnosing tool.

Patients and Methods

This study included 29 patients with liver SNNs, out of which 14 had no clinical symptoms and were discovered by routine ultrasound examinations, six were found by computed tomography (CT) due to abdominal illness, four had ovarian tumors, and five had gastrointestinal cancer surgeries, previously. Histologically, these SNNs can be divided into three subtypes, i.e., type I, pure coagulation necrosis (14 cases); type II, coagulation necrosis mixed with liquefaction necrosis (five cases); and type III, multi-nodular fusion (10 cases). CT and magnetic resonance imaging (MRI) patterns were shown to be associated with SNN histology. All patients were treated surgically with good prognosis.

Results

CT and MRI appearance and correlation with pathology types: three subtypes of lesions were hypo-density on both pre contrast and post contrast CT, 12 lesions were found the enhanced capsule and 1 lesion of multi- nodular fusion type showed septa enhancement. The lesions were hypo-intensity on T2WI and the lesions of type II showed as mixed hyperintensity on T2WI. The capsule showed delayed enhancement in all cases, and all lesions of multi- nodular fusion type showed delayed septa enhancement on MR images. 15 cases on CT were misdiagnosed and Four cases on MRI were misdiagnosed and the accuracy of CT and MRI were 48.3% and 86.2% respectively.

Conclusions

In conclusion, CT and MRI are useful tools for SNN diagnosis.     

The Use of Functional Magnetic Resonance Imaging to Test Pharmacotherapies for Alcohol Use Disorder: A Systematic Review

Alcohol use disorder (AUD) is a chronic relapsing condition that represents a significant public health concern. Pharmacological treatment development for AUD is a top research priority, and many studies are being conducted to evaluate potential AUD treatments. Understanding the brain circuitry impacted by addiction is crucial for the development of efficacious pharmacological interventions. These neuroadaptations can be probed noninvasively using functional magnetic resonance neuroimaging (fMRI). fMRI may be an effective tool to identify biomarkers for AUD pharmacotherapies, evaluating changes associated with pharmacological treatment. Thus, the present qualitative review of the literature focuses on the role of fMRI as a tool for medication development for AUD. The aim of this review was to assemble research across a range of fMRI paradigms to study the effectiveness of pharmacological treatments of adult AUD. First, we present a qualitative review of fMRI AUD pharmacotherapy studies, differentiating studies based on their dosing regimen. Second, we provide recommendations for the field to improve the use of fMRI as a biomarker for AUD pharmacotherapy.     

Cauda equina syndrome complicating ankylosing spondylitis: Role of computed tomography and magnetic resonance imaging

Summary We present two cases of cauda equina syndrome in ankylosing spondylitis. Cauda equina syndrome is a rare complication of ankylosing spondylitis, the pathogenesis of which is not well understood. The onset is insidious with pain and sensory symptoms; sphincter disturbances are common. After a period of increasing neurological symptoms, the condition tends to stabilize. The degree of nerve involvement is variable and can be accurately defined by electromyography. The diagnosis has to be confirmed by computed tomography (CT) or magnetic resonance imaging (MRI); myelography must be avoided. There is no specific treatment, except for pain control.The different clinical presentations and the role of new imaging techniques, CT and MRI, are demonstrated.     

Fetal Alcohol Syndrome: A Case Report of Neuropsychological, MRI, and EEG Assessment of Two Children

Neuropsychological, neuroanatomical, and electrophysiological data are presented on two subjects with fetal alcohol syndrome (FAS). Both boys had intelligence quotients in the mentally deficient range and were found to have several other severe, specific deficits. Magnetic resonance imaging showed abnormalities of the corpus callosum, and reductions in the size of the basal ganglia and thalamic structures. No focal abnormalities were noted in the electroencephalogram records, although the electroencephalograms of both boys were moderately abnormal for their age group. A multidisciplinary approach to the study of FAS, hopefully will lead to a more unified concept of the disorder and perhaps indicate specific areas of vulnerability.     

Abnormal Development of the Cerebellar Vermis in Children Prenatally Exposed to Alcohol: Size Reduction in Lobules I–V

Abnormalities of the cerebellar vermis have been well documented in animal models of fetal alcohol syndrome. At this point, it is not known if the same brain region is affected in humans prenatally exposed to alcohol. In this study, the area of the cerebellar vermis was measured from brain magnetic resonance images of 9 children and young adults with prenatal alcohol exposure and 24 control subjects in the same age range. Six of the exposed children met standard criteria for fetal alcohol syndrome. The remaining three subjects had significant histories of prenatal exposure to alcohol, but did not have enough of the classic facial features for the diagnosis. For each subject with a suitable midsagittal section, three vermal areas were circumscribed: anterior vermis (vermal lobules I–V), posterior vermis (vermal lobules VI and VII), and the remaining vermal area (including lobules VIII–X). Statistical analyses revealed that the anterior region of the vermis was significantly smaller in subjects with prenatal alcohol exposure, whereas the posterior region and the remaining vermal area did not differ between groups. Previous findings from an animal model of neonatal alcohol exposure have documented Purkinje cell loss in vermal lobules I–V and IX–X, with notable sparing in lobules VI–VII. Thus, the results of both studies indicate similar patterns of abnormal brain development in the anterior vermal region, with apparent sparing in the posterior vermal region. Our findings, for the first time, suggest that regionally specific Purkinje cell death may also occur in humans prenatally exposed to alcohol.     

Epicardial Fat: Definition,Measurements and Systematic Review of Main Outcomes

Epicardial fat (EF) is a visceral fat deposit, located between the heart and thepericardium, which shares many of the pathophysiological properties of other visceralfat deposits, It also potentially causes local inflammation and likely has directeffects on coronary atherosclerosis. Echocardiography, computed tomography andmagnetic resonance imaging have been used to evaluate EF, but variations betweenmethodologies limit the comparability between these modalities.We performed a systematic review of the literature finding associations of EF withmetabolic syndrome and coronary artery disease. The summarization of theseassociations is limited by the heterogeneity of the methods used and the populationsstudied, where most of the subjects were at high cardiovascular disease risk.EF is also associated with other known factors, such as obesity, diabetes mellitus,age and hypertension, which makes the interpretation of its role as an independentrisk marker intricate. Based on these data, we conclude that EF is a visceral fatdeposit with potential implications in coronary artery disease. We describe thereference values of EF for the different imaging modalities, even though these havenot yet been validated for clinical use. It is still necessary to better definenormal reference values and the risk associated with EF to further evaluate its rolein cardiovascular and metabolic risk assessment in relation to other criteriacurrently used.     

MRI和增强CT诊断重症急性胰腺炎的比较研究

背景：CT尤其是增强CT（CECT）是判断急性胰腺炎严重程度和预后的重要方法,然而近年MRI有取代CT的趋势。目的：比较MRI与CECT诊断重症急性胰腺炎（SAP）的准确性。方法：2006年1月-2008年9月于泰州市人民医院确诊为SAP的住院患者纳入研究。回顾性分析人选患者的临床以及MRI和CECT表现,以Bahhazar分级系统评估MRI严重指数（MRSI）和CT严重指数（CTSI）。结果：共36例患者临床评估为SAP,入院2d内和第7d的MRSI与C偈I无明显差异。MRI诊断SAP的准确率高于CECT（94．4％对83.3％）,但差异无统计学意义（P〉0．05）。结论：MRI用于SAP的诊断,效果与CECT相似且禁忌证相对较少,是判断急性胰腺炎严重程度的可靠方法。