Magnetic resonance imaging of the brain in alcoholics: cerebral atrophy, lifetime alcohol consumption, and cognitive deficits

Mr Imaging of Chronic Alcoholism

We evaluated the brain lesions of patients with chronic alcoholism (n = 34) in comparison with age- and sex-matched controls (n = 40) by MR imaging. T1-weighted sagittal and axial images and T2-weighted axial images were obtained with a 0.5 T superconducting MR unit. Various brain measurements were then performed, and the presence of regions of abnormal signal intensity was also compared between the two groups. The brain measurements revealed significant cerebral atrophy (characterized by lateral and 3rd ventricular dilatation, and widening of the interhemispheric fissure) as well as significant cerebellar atrophy (represented by 4th ventricular dilatation) in the alcoholic group. These changes were more prominent in patients in their fifties and sixties than in those aged in the thirties and forties. Focal hypointense lesions were observed in 20.6% of the alcoholics and in 5% of the controls (p < 0.01), while focal hyperintense lesions were observed in 61.8% of the alcoholics and in 20% of the controls (p < 0.001). The severity of these MR findings correlated well with the age of the patients. These observations suggest that alcohol is an important promotor of brain aging.

The effects of head circumference (HC) and lifetime alcohol consumption (AC) on cognitive function in the elderly

Smaller premorbid brain volume is known to be related to cognitive deterioration in older adults, supporting a reserve hypothesis of brain aging. Heavy lifetime alcohol consumption (AC) may also increase the risk of cognitive impairment. The aim of this study was to examine the effects of head circumference (HC) and lifetime AC on cognitive function in the elderly. This study is part of a large, longitudinal study of men aged 60 years or older in the Korean community. We studied 1569 subjects with complete demographic, anthropometric and AC data. Cognitive function was assessed by the Korean version of Mini Mental State Examination (K-MMSE). Participants reported at the time of interview their lifetime alcohol drinking patterns. HC was also measured. We did a cross-sectional analysis the relation between two factors to cognitive function. After a multivariable adjustment, the interactive effect between HC and lifetime AC was shown to be significantly associated with cognitive function (F=2.55, p=0.038). Simple main effect analysis showed that smaller HC and a high level of lifetime AC were related with decreased cognitive function. All these findings suggest the possibility that lifetime AC and HC have synergistic effects on cognitive impairment.

Hepatic encephalopathy is associated with posttransplant cognitive function and brain volume

Hepatic encephalopathy (HE) is a common complication of cirrhosis that is associated with brain atrophy and may participate in impaired cognitive function after liver transplantation. This study analyzes the relationship of HE with cognitive function and brain volume after transplantation. A total of 52 consecutive patients with cirrhosis (24 alcohol abuse, 24 prior HE, 14 diabetes mellitus) completed a neuropsychological assessment before liver transplantation and again, 6 to 12 months after transplantation. In 24 patients who underwent the posttransplant assessment, magnetic resonance imaging was performed in addition, with measurement of brain volume and relative concentration of N-acetylaspartate (NAA) and creatine/phosphocreatine (Cr), a neuronal marker, by magnetic resonance spectroscopy. Neuropsychological assessment prior to transplantation identified minimal HE in 28 patients. All cognitive indexes improved after liver transplantation, but 7 patients (13%) showed persistent mild cognitive impairment. Global cognitive function after transplantation was poorer in patients with the following variables before liver transplantation: alcohol etiology, diabetes mellitus, and HE. Brain volume after transplantation was smaller in patients with prior HE. Brain volume correlated to NAA/Cr values (r = 0.498, P = 0.013) and poor motor function (r = 0.41, P = 0.049). In conclusion, the association of HE with cognitive function and brain volume suggests that having experienced HE before liver transplantation impairs the posttransplantation neurological outcome.

Association between alcohol consumption and diabetic retinopathy and visual acuity-the AdRem Study

AIMS

We investigated the association between alcohol consumption and diabetic retinopathy and deterioration of visual acuity in individuals with Type 2 diabetes.

METHODS

We conducted a cohort analysis of 1239 participants with Type 2 diabetes aged 55-81 years enrolled in the AdRem study, a sub-study of the Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation (ADVANCE) trial. Current and past consumption of wine, spirits and beer was measured by self-report. Moderate and heavy alcohol consumption was defined as 1-14 and >14 drinks/week, respectively. Diabetic retinopathy, measured by mydriatic stereoscopic seven-field retinal photography, was defined by a 2-step progression in the Early Treatment of Diabetic Retinopathy Study (ETDRS) score or the presence of any retinal vascular lesions. Deterioration of visual acuity was defined by a decrease of two lines in best vision in either eye, measured corrected, or through a pinhole using a Snellen chart.

RESULTS

In a mean follow-up of 5.5 years, we identified 182 participants with a 2-step progression in the ETDRS score, 640 participants with the presence of any retinal vascular lesions and 693 participants with a deterioration of visual acuity. Current moderate consumption of alcohol, compared with no current consumption, was not associated with presence or progression of diabetic retinopathy; however, it was associated with higher risk of deterioration of visual acuity (multivariable-adjusted OR 1.83; 95% CI 1.34-2.48; P<0.001).

CONCLUSIONS

Alcohol consumption is associated with increased risk of deterioration of visual acuity, but not with retinopathy in individuals with Type 2 diabetes.

Dementia syndromes: evaluation and treatment

As our population ages, diseases affecting memory and daily functioning will affect an increasing number of individuals, their families and the healthcare system. The social, financial and economic impacts will be profound. This article provides an overview of current dementia syndromes to assist clinicians in evaluating, educating and treating these patients.

Reduced glial and neuronal packing density in the orbitofrontal cortex in alcohol dependence and its relationship with suicide and duration of alcohol dependence

BACKGROUND

Reduced metabolism, blood flow, and tissue volume have been detected in the dorsolateral prefrontal cortex (dlPFC) of neurologically intact alcoholic subjects and these deficits are accompanied by lower density of neurons and glial cells. Another prefrontal region, the orbitofrontal cortex (ORB), functionally and structurally differentiated from the dlPFC, and heavily involved in decision-making processes, also shows functional alterations in alcoholic subjects. However, it is unknown whether changes in the packing density of neurons or glial cells also occur in the ORB and whether that density may be related to the increased suicide probability of alcoholic subjects or to the duration of alcohol dependence.

METHODS

The present study used a 3-dimensional cell-counting method in postmortem brain tissue to determine the packing density of neurons and glial cells in the ORB (area 47) of 15 subjects with alcohol dependence (8 suicides, 7 nonsuicides) and 8 normal controls and to determine whether cell density is correlated with suicide and duration of alcohol dependence.

RESULTS

There was a significantly lower density of both neurons (by 27%) and glial cells (by 25%) in the ORB of alcoholic subjects compared with controls. Packing density of either neurons or glial cells was not significantly different in alcoholic suicides compared with alcoholic nonsuicides. Age was not correlated with neuronal or glial density in either group. However, the duration of alcohol dependence and the ratio of that duration to the length of life span were significantly and negatively correlated to the overall density of neurons.

CONCLUSION

The present results indicate that alcohol dependence is associated with a decrease in the packing density of neurons and glia in the ORB and that the reduction in neuronal but not glial density progresses with the duration of alcohol dependence.

Effects of moderate alcohol consumption on cognitive function in women

BACKGROUND

The adverse effects of excess alcohol intake on cognitive function are well established, but the effect of moderate consumption is uncertain.

METHODS

Between 1995 and 2001, we evaluated cognitive function in 12,480 participants in the Nurses' Health Study who were 70 to 81 years old, with follow-up assessments in 11,102 two years later. The level of alcohol consumption was ascertained regularly beginning in 1980. We calculated multivariate-adjusted mean cognitive scores and multivariate-adjusted risks of cognitive impairment (defined as the lowest 10 percent of the scores) and a substantial decline in cognitive function over time (defined as a change that was in the worst 10 percent of the distribution of the decline). We also stratified analyses according to the apolipoprotein E genotype in a subgroup of women.

RESULTS

After multivariate adjustment, moderate drinkers (those who consumed less than 15.0 g of alcohol per day [about one drink]) had better mean cognitive scores than nondrinkers. Among moderate drinkers, as compared with nondrinkers, the relative risk of impairment was 0.77 on our test of general cognition (95 percent confidence interval, 0.67 to 0.88) and 0.81 on the basis of a global cognitive score combining the results of all tests (95 percent confidence interval, 0.70 to 0.93). The results for cognitive decline were similar; for example, on our test of general cognition, the relative risk of a substantial decline in performance over a two-year period was 0.85 (95 percent confidence interval, 0.74 to 0.98) among moderate drinkers, as compared with nondrinkers. There were no significant associations between higher levels of drinking (15.0 to 30.0 g per day) and the risk of cognitive impairment or decline. There were no significant differences in risks according to the beverage (e.g., wine or beer) and no interaction with the apolipoprotein E genotype.

CONCLUSIONS

Our data suggest that in women, up to one drink per day does not impair cognitive function and may actually decrease the risk of cognitive decline.

Individual differences in latent neuropsychological abilities at addictions treatment entry

The latent structure of neuropsychological abilities and risk factors for impairment were examined in 197 persons entering addictions treatment. Confirmatory factor analysis yielded 4 factors: Executive, Memory, Verbal, and Processing Speed. The measurement model was consistent with evidence that neuropsychological test performance is factorially complex and supported by multiple brain regions. Path analyses showed that risk factors explained 34%-57% of the true variance in abilities. Age, education, and medical status had the most generalized and robust associations with abilities. Drug use disorder diagnoses, childhood behavior problems, familial alcoholism, and psychopathology were also significantly related to specific latent abilities. Knowledge of neuropsychological impairment may be clinically useful, and selected risk factors may help treatment providers decide which clients should receive formal neuropsychological assessment.

Alcohol consumption and subclinical findings on magnetic resonance imaging of the brain in older adults: the cardiovascular health study

BACKGROUND AND PURPOSE

Subclinical findings on MRI of the brain are associated with poorer cognitive and neurological function among older adults. We sought to determine how alcohol consumption is related to these findings.

METHODS

As part of the Cardiovascular Health Study, 3660 adults aged 65 years and older underwent MRI of the brain from 1992 to 1994. We excluded 284 participants with a confirmed history of cerebrovascular disease. We assessed self-reported intake of beer, wine, and liquor at the annual clinic visit closest to the date of the MRI and grouped participants into 6 categories: abstainers, former drinkers, <1 drink weekly, 1 to <7 drinks weekly, 7 to <15 drinks weekly, and >/=15 drinks weekly. Neuroradiologists assessed white matter grade, infarcts, ventricular size, and sulcal size in a standardized and blinded manner. We used multivariate regression to control for sociodemographic and clinical characteristics.

RESULTS

We found a U-shaped relationship between alcohol consumption and white matter abnormalities. Compared with abstainers, individuals consuming 1 to <7 drinks had an OR of 0.68, and those consuming >/=15 drinks weekly had an OR of 0.95 (p for quadratic term=0.01). Heavier alcohol consumption was associated with a lower prevalence of infarcts (OR for >/=15 drinks weekly relative to abstainers 0.59; P for trend=0.004), but larger ventricular size (OR for >/=15 drinks weekly relative to abstainers 1.32; P for trend=0.006) and sulcal size (OR for >/=15 drinks weekly relative to abstainers 1.53; P for trend=0.007).

CONCLUSIONS

Moderate alcohol consumption is associated with a lower prevalence of white matter abnormalities and infarcts, thought to be of vascular origin, but with a dose-dependent higher prevalence of brain atrophy on MRI among older adults. The extent to which these competing associations influence overall brain function will require further study.

Brain shrinkage in alcoholics: a decade on and what have we learned?

Brain atrophy in alcoholics has been identified using both radiological and pathological techniques. However the magnitude and topography of the atrophy, and the factors which contribute to it, are unclear. This review compares the results of imaging and pathological studies in alcoholics examining variables which may contribute to any discrepancies. We conclude that significant brain damage does occur as a result of alcohol abuse per se, that the damage is regionally specific with the frontal lobes being particularly affected, and that both grey matter and white matter components are damaged.

Brain imaging in alcoholism

Copyright Rapid Science Ltd

Brain impairment in well-nourished chronic alcoholics is related to ethanol intake

To determine the influence of chronic ethanol intake on the central nervous system, we studied 40 asymptomatic, well-nourished, chronic alcoholics (mean age, 42.6 +/- 9.1 years) and 20 age-, sex-, and education-matched control subjects. Studies included neuropsychological testing, visual and short-latency auditory evoked potentials, and morphometric analysis of computed tomography scans. The mean daily ethanol consumption of the alcoholics was 204 gm over an average of 26.4 years. Compared to control subjects, chronic alcoholics exhibited a significant prolongation of the P100 latency of visual evoked potentials, and a prolongation and reduction in the amplitude of the latency of the V wave of short-latency auditory evoked potentials. These abnormalities were related to the lifetime dose of ethanol consumed. Brain morphometric analysis showed that alcoholics had a significantly greater degree of brain shrinkage with age, compared to control subjects. The cortical atrophy index correlated significantly with the lifetime ethanol consumption. Neuropsychological testing in alcoholics compared to controls revealed a significant impairment of frontal skills that was related to age, degree of scholarship, and the presence of frontal atrophy. In conclusion, well-nourished chronic alcoholics exhibited significant brain impairment, as demonstrated by neuropsychological testing, evoked potentials, and brain morphometric analysis, which was correlated with the lifetime dose of ethanol consumed.

Atrophy of the corpus callosum in chronic alcoholism

To determine the prevalence of corpus callosum atrophy in chronic alcoholics and its relationship to cognitive function and brain atrophy, a prospective clinicoradiologic study was carried out in 28 right-handed male patients with chronic alcoholism and 14 age- and sex-matched right-handed control subjects. Clinical evaluation, neuropsychological testing and measurement of the midsagittal corpus callosum area and thickness (genu, truncus and splenium), as well as the frontal lobe index and the width of the cortical sulci on T1- and T2-weighted magnetic resonance images were performed. Compared to controls, alcoholics had significantly decreased corpus callosum area and thickness, mainly in the genu. Two-thirds had a corpus callosum area 2 SD below the mean of the control group. The sagittal area of the corpus callosum body correlated negatively with the degree of frontal and cortical atrophies (r = -0.5579 and -0.6853, respectively p < 0.01, both). Alcoholics with corpus callosum atrophy exhibited impairment of visual and logical memories (p < 0.05 both) and those with reduced thickness of the genu showed impairment of frontal lobe tasks (p < 0.05). The reduction of corpus callosum indices (age-corrected) also correlated with the total lifetime dose of ethanol consumed (r = 0.6107, p < 0.001), but was not related to nutritional status or electrolyte imbalance. Atrophy of the corpus callosum is common among alcoholic patients and may reflect the severity and pattern of cortical damage. The degree of this atrophy also correlated with the severity of ethanol intake.

Traumatic brain injury, alcohol and quantitative neuroimaging: preliminary findings

Magnetic resonance (MR) quantitative neuroimaging analysis was undertaken with a large group of normal (n = 197) and traumatically brain injured (TBI, n = 99) adults. Of the TBI subjects 18 patients were identified with a history of substance-related abuse (TBI/Abuse group). Both the TBI/ Abuse group and the remaining sample of TBI patients (n = 81, TBI/Non-abuse group) without a history of substance-related abuse differed significantly from the control group on most quantitative MR imaging analyses. The TBI/Abuse group displayed the greatest degree of atrophic change. However, the TBI/Abuse group had a significantly lower Glasgow Coma Scale (GCS) score, ostensibly suggesting that those with substance-related abuse suffered more severe brain injury than non-abuse TBI patients. When a subset (n = 18) of the TBI/Non-abuse group was matched by GCS, gender and age to the TBI/Abuse group, both groups differed significantly from the control group on most morphometric measures, but did not differ from one another. Results are discussed in terms of the potential adverse role that substance-related abuse, particularly alcohol, plays in the individual who sustains traumatic injury to the brain.

Magnetic resonance imaging reveals no ventriculomegaly in polydrug abusers

Previous studies of cerebral structure in substance abusers yielded controversial results, largely due to issues of subject selection and/or limitations of experimental techniques. The purpose of the present study was to assess whether the ventricle-to-brain ratio (VBR), determined volumetrically by magnetic resonance imaging (MRI), differed in polysubstance abusers (n = 10), as compared with age-matched controls (n = 10). Subjects were male volunteers 21-39 years of age. The values of VBR in the polydrug abuse group were not larger than those in control group, nor was there any tendency toward relative ventriculomegaly in the substance abusers. Therefore, the present findings provide no evidence that polysubstance abuse produces abnormalities of gross brain structure in relatively young and physically healthy men.

Effects of chronic alcohol abuse and HIV infection on brain phosphorus metabolites

We examined the effects of human immunodeficiency virus (HIV) infection and chronic alcohol consumption on cerebral phosphorus metabolites to determine if chronic alcohol abuse is a risk factor for the progression of neurological effects of HIV infection. We studied 15 HIV- alcoholics, 8 HIV- light/nondrinkers, 32 HIV+ alcoholics, and 41 HIV+ light/nondrinking men, with both HIV+ groups having similar CD4 lymphocyte counts. We used localized 31-phosphorus magnetic resonance spectroscopy after magnetic resonance imaging to examine two brain volumes in superior white matter and subcortical gray matter. Chronic alcohol consumption was associated with reduced white matter concentrations of phosphodiester (PDE) and phosphocreatine (PCr). Also in the white matter, acquired immune deficiency syndrome (AIDS) and AIDS-related complex (ARC) were associated with reduced concentrations of PDE and PCr, compared with both HIV- and clinically asymptomatic HIV+ subjects. Because no alcohol-by-HIV interactions were detected, the effects of HIV infection and alcohol abuse were cumulative. This is reflected in a successive decrease of white matter PDE and PCr concentrations in the order HIV- light/nondrinkers/HIV- alcoholics/HIV+ light/nondrinkers/HIV+ alcoholics. Subcortical gray matter PDE concentrations were lower in ARC/AIDS alcoholics than in HIV- light/nondrinking individuals. These findings suggest altered brain phospholipid metabolites and energy metabolites with alcohol abuse and HIV infection. They demonstrate that the adverse metabolic effects of HIV on the brain are augmented by chronic alcohol abuse.

Neuroimaging in alcoholism: CT and MRI results and clinical correlates

For more than a century we have known the deleterious effects of alcohol on the brain regions surrounding the third ventricle and on the cerebellum. But it was only recently that we gained clearer evidence that the cortex is affected as well. Our imaging studies show that brain shrinkage is at least partially reversible once abstinence is maintained. They confirm results obtained in different laboratories from all over the world. Although our data contradict the rehydration hypothesis and thus lend credence to the idea of regeneration and neuroplasticity, the nature of reversibility is still a matter of debate.

Acute ethanol decreases NMR relaxation times of water hydrogen protons in fish brain

The traditional belief about ethanol's mechanism of action is based on ethanol's lipophilicity and capability to penetrate and disorder lipid bilayers. This traditional belief is now being supplanted by growing evidence that ethanol has relatively selective actions on certain synaptic receptors, such as those for NMDA, serotonin, and GABA. It was recently argued that these receptor specificities are secondary to a preferential ability of ethanol to displace membrane bound water in the domains of certain receptors. The data obtained in this study are consistent with the original hypothesis: any disorganization of cellular water by ethanol will be detectable by proton nuclear magnetic resonance (NMR) spectroscopy. In particular, the relaxation times of water hydrogen protons reflect how constrained water molecules are by the macromolecules within cells. The relaxation time of "bulk" water is lengthened relative to water molecules that are under the influence of electromagnetic fields of macromolecular surfaces within cells. Here, we tested this hypothesis in living fish, which dosed themselves by swimming in water that had added ethanol. Estimates of brain alcohol at 5 min after initial exposure revealed that the brain concentration was only about 1/3 that of the water in which they were swimming. The average value of the NMR relaxation time T1, but not T2, was decreased at 5 min (when brain concentrations were on the order 100 mM) and reached statistical significance at 10 and 30 min after initial exposure.(ABSTRACT TRUNCATED AT 250 WORDS)

Correlation between event-related potentials and MR measurements in chronic alcoholic patients

Event-related potentials were recorded in 25 abstinent alcoholics, and 25 gender- and age-matched controls during a two-tone discrimination (odd ball) task. All the subjects were free from medication and dextral. MR images were examined in the alcoholics. The amplitudes of N100, N200 and P300 in the alcoholics were reduced compared with those of the controls. In order to identify morphological changes responsible for ERP abnormalities, linear regression analyses were performed between ERP measures and MRI parameters. The amplitude of N100 was inversely correlated with ventricular size. The amplitudes of P300 were inversely correlated with both ventricular size and width of cortical sulci. It was suggested that the N100 abnormality was related to subcortical structure, and P300 alteration was related to both subcortical and cortical structures in the alcoholics.

Neuropsychological measures and event-related potentials in alcoholics: interrelationships, long-term reliabilities, and prediction of resumption of drinking

Sober male and female alcoholics and peer controls were tested and then retested 14 months later on neuropsychological performance tests (NTP) and also had event-related potentials (ERPs) recorded (non-concurrently) to visual stimulation. Both NTP and ERP measures distinguish male alcoholics from peer controls at test and retest; NTP, but not ERP, scores distinguish female alcoholics from peer controls. Both measures manifest moderate to high reliabilities over time and are correlated modestly. NTP and ERP measures obtained at the end of treatment predict future resumers and abstainers 8 to 14 months later. The results demonstrate the utility of biopsychological approaches to alcoholism and support Grant's (1986) concept of alcoholics as suffering from an intermediate duration (subacute) organic mental disorder.

Small animal magnetic resonance imaging: a means of studying the development of structural pathologies in the rat brain

Small animal magnetic resonance imaging (SAMRI) was developed to detect structural tissue changes associated with disease states in animal models. The disease state of particular interest here is that associated with long-term alcohol abuse. The small animal model used for this study was the thiamine-deficient Sprague-Dawley rat, a model that provides a relatively rapid means of mimicking the ventriculomegaly frequently found in human chronic alcohol abusers. A custom-designed coil tuned to the magnetic field of a 1.5 Tesla clinical magnetic resonance imager provided the technology necessary to delineate discreet regions of the rat brain with clarity. Adult, male rats were imaged, placed on a thiamine-deficient pellet diet for approximately 6 weeks, and then reimaged. Treatment associated enlargement of the lateral ventricles identified in the images was verified by posttreatment histological analysis of the brains of these rats. The results demonstrated that SAMRI is capable of providing dramatic and reliable visual evidence of pathological structural changes in small tissue volumes with high resolution and reproducibility. Furthermore, the noninvasiveness of SAMRI allowed for imaging of the same animals over time, thereby reducing the numbers of animals needed for convincing documentation of the changes in ventricular size.

Abnormalities in event-related potentials: N100, N200 and P300 topography in alcoholics

Event-related potentials were recorded in 30 abstinent alcoholics, and 30 gender- and age-matched controls during a two-tone discrimination (odd ball) task. All the subjects were free from medication and dextral. The amplitudes of N100, N200 and P300 in the alcoholics were reduced and the P300 latency prolonged as compared with those of the controls. A P300 amplitude reduction occurred in the left and midline frontal, and the left and midline central regions. This is the first report of the amplitude of P300 being markedly decreased in the left hemispheres of the brains of the alcoholics. The results are discussed in terms of the cognitive dysfunctions of alcoholics.

Brain morphologic characteristics of cirrhotic alcoholics and cirrhotic nonalcoholics: an MRI study

Cirrhotic alcoholics, cirrhotic nonalcoholics, and normal controls were compared on planimetric and subjective ratings of the MRI of the brain. The results indicated that the cirrhotic alcoholics exhibited more gross pathology than the nonalcoholic cirrhotics on ratings of frontal, parietal, and cerebellar atrophy; however, these groups were more similar to each other than they were different on planimetric measurements. The results are discussed in terms of the etiology and localization of the neuropathologic sequelae found commonly among alcoholics.

Alcohol, head injury, and neuropsychological function

Evidence is reviewed indicating that the extent of alcohol abuse alone cannot account for the neuropsychological deficits observed in alcoholics, and that alcohol abuse and head injury may interact in some patients to influence neuropsychological status. Alcohol abuse both increases the risk for head trauma and potentiates the resulting brain injury, which can lead to negative neuropsychological consequences. Clinicians involved in the treatment of addiction should assess patients for history of head injury, and neuropsychological deficits consequent to both head injury and ethanol. These deficits may limit patient ability to comply with addiction rehabilitation programs. Conversely, clinicians in acute care and rehabilitation of the sequelae of head trauma should routinely assess their patients for substance abuse, because such abuse can have a significant impact on recovery from brain injury.

Quantitative magnetic resonance imaging in heroin- and cocaine-dependent men: a preliminary study

Quantitative magnetic resonance imaging (MRI) of the brain was performed in nine drug-dependent men with a primary diagnosis of opioid and/or cocaine dependence, and 10 age-matched, non-drug-dependent controls. Individuals were screened for the presence of gross cerebral abnormalities before T1 and T2 analyses. Regional T1 and T2 times were calculated on a single 5-mm thick axial slice positioned just below the caudal margin of the lateral ventricles, passing through the caudate and putamen. A voxel of interest (VOI) cursor was placed bilaterally within the putamen, caudate, frontal gray matter, frontal white matter, or posterior white matter. T1 and T2 values were determined for each VOI using an iterative chi 2 minimization program. T1 and T2 relaxation times did not differ significantly between the subject groups in any brain region studied. These results suggest that T1 and T2 relaxation times may not identify microstructural central nervous system changes resulting from chronic opiate and cocaine abuse.

Alzheimer's disease and alcoholism: possible interactions

The purpose of this investigation was to test the hypothesis that chronic exposure to alcohol may accelerate Alzheimer's disease (AD), either by independently adding receptor losses or by accelerating the AD disease process itself. Muscarinic [3H]quinuclidinyl benzilate and benzodiazepine [3H]-flunitrazepam receptor binding in homogenates of human autopsy brains were determined in four nonalcoholic and seven alcoholic AD brains and in histologically normal brains from 20 alcoholics and 20 nonalcoholics. Muscarinic binding was decreased in alcoholic AD compared with nonalcoholic AD in the parahippocampal region of frontal cortex, premotor temporal cortex, and amygdala, but not in the hippocampus. Benzodiazepine receptors were lost from the temporal cortex and amygdala, but the difference in the amygdala was not statistically significant. Plaque counts considered a marker of the severity of AD were not increased in the brains of alcoholics compared with nonalcoholics. Larger receptor losses in some alcoholic AD were associated with low plaque counts. Since all of these patients were severely demented, it is tentatively suggested that the receptor losses resulting from alcoholism may have contributed to the dementia in these AD patients.

T1 and T2 relaxation time estimates and brain measures during withdrawal in alcoholic men

Twenty-four chronic alcoholic men were investigated with 0.02 Tesla/0.8 MHz magnetic resonance imaging on days 7-9 of acute alcohol withdrawal state. Estimates of T1 and T2 relaxation times were obtained from the white matter and basal ganglia nuclei in an axial section. This section was also used for area measurements of intracranial structures using computer-assisted tissue classification. The relation between T1 and age was more marked in the alcoholic patients than in the control group. Mean values of T1 and T2 did not differ between the two groups, but differences in the age dependence of T1 were highly significant for all regions. The number of years of drinking was influential to T1, but to a lesser extent than age. Lateral ventricular area correlated significantly with T1 of the white matter in the alcoholic patients. Using visual ratings of the entire intracranial volume the alcoholic patients demonstrated wider lateral ventricles and cortical sulci, but there was no increased frequency of white matter lesions.

Reduced cerebral grey matter observed in alcoholics using magnetic resonance imaging

Twenty-eight chronic alcoholics and 36 age- and sex-matched non-alcoholic controls were examined with magnetic resonance imaging and brain morphometric analyses. Results confirmed large increases in subarachnoid cerebrospinal fluid (CSF) volume and mild ventricular enlargement in the alcoholics and revealed associated volume reductions of localized cortical and subcortical cerebral structures. Volume losses in the diencephalon, the caudate nucleus, dorsolateral frontal and parietal cortex, and mesial temporal lobe structures were the most prominent. Significant correlations between increments in cortical and ventricular CSF and decrements in the volume of cortical and subcortical grey matter were noted. Although there was little evidence for relationships between performance on neuropsychological tests and volume of grey matter structures, significant correlations between some cognitive measures and subcortical and cortical fluid volumes were found. The parallels between this pattern of affected structures and recent neuropathological findings are discussed.

Neuroimaging studies of schizophrenia

Neuroimaging studies of schizophrenia have identified abnormalities in neuroanatomy, regional brain metabolism and receptor physiology. Computerized tomographic (CT) studies have demonstrated gross ventricular and sulcal enlargement. These findings are probably nonprogressive, and it is not yet clear whether they are present only in a subgroup of patients; whether they represent a reduction in tissue from a previously normal condition or an abnormality in brain development; and what relationship they have to genetic risk for schizophrenia, clinical features, or longterm prognosis. Magnetic resonance imaging (MRI) studies, which offer higher resolution and greater flexibility in imaging plane, are currently focussing on specific neuroanatomic sites, such as the limbic system, basal ganglia and frontal cortex, implicated by neuropathological or clinical studies in the pathophysiology of schizophrenia. Positron emission tomographic (PET) scanning now enables investigators to study brain metabolism and receptor physiology. Evidence to date suggests that there may be significant abnormalities in the pattern of cerebral glucose utilization as well as in the density of dopamine receptors in patients with schizophrenia. Much future work is needed to determine the sensitivity and specificity of these observations as well as the extent to which they are affected by changes in clinical state, attention and medication exposure.

Emotional perception and memory in alcoholism and aging

The ability to identify and recognize emotional materials was studied in 10 male alcoholic Korsakoff patients, 27 male non-Korsakoff alcoholics, and 31 male nonalcoholic controls, across a wide age range (23 to 77 years). Stimulus materials were presented in two sensory modalities; the materials were photographs of faces expressing one of four emotions (happy, sad, angry, or neutral), and recordings of sentences with emotional intonations or semantic meanings expressing the same four emotions. Results of the experiments showed consistently severe deficits in emotional functions in the Korsakoff patients, but only minor alterations in the non-Korsakoff alcoholics. Older subjects, whether or not they had a history of alcoholism, also exhibited significant deficits on most of the tasks. Results of the study did not provide strong support for the premature aging hypothesis of alcoholism, which suggests that alcoholism accelerates aging, beginning either at the onset of heavy drinking early in adult life, or later in life after the normal manifestations of aging have begun to appear. Results are related to brain mechanisms in emotional perception and memory functions.