Computed tomography of the brain, clinical examination and neuropsychological assessment of a random sample of men from the general population

Sex differences in alcohol-related neurobehavioral consequences

In this chapter, we review existing research regarding sex differences in alcohol's effects on neurobehavioral functions/processes. Drawn largely from laboratory studies, literature regarding acute alcohol administration and chronic alcohol misuse is explored focusing on commonly employed neuropsychologic domains (e.g., executive function, visuospatial skills, learning and memory, gait and balance), neurophysiologic measures (e.g., electroencephalography and event-related potentials), and structural and functional neuroimaging (e.g., magnetic resonance imaging (MRI), functional MRI, diffusion tensor imaging, positron emission tomography, and magnetic resonance spectroscopy). To provide a historical perspective on the development of these questions, we have included reference to early and more recent research. Additionally, specific biases, knowledge gaps, and continuing controversies are noted.

Nutritional cerebellar degeneration, with comments on its relationship to Wernicke disease and alcoholism

Nutritional cerebellar degeneration occurs in alcoholism and other states that predispose to malnutrition, such as gastric bypass surgery. Gait ataxia is the principal clinical manifestation. Ataxia of the lower limbs is not uncommon, but upper extremity ataxia and nystagmus are rare. Atrophy of the anterior superior vermis is the primary pathological manifestation in established disease. Typically, the onset is subacute. This cerebellar disease is part of the spectrum of the Wernicke-Korsakoff syndrome, i.e. the cerebellar manifestation of Wernicke disease. It may occur with other lesions of Wernicke disease or in isolation. Rarely, with florid disease, lesions may be hemorrhagic. Active disease should be treated with thiamine in the same way that one treats Wernicke disease. Clinicopathologic correlation in this disease has provided the best evidence that the anterior superior vermis is important in coordinating bipedal locomotion.

Neuropsychological and sensory gating deficits related to remote alcohol abuse history in schizophrenia

Recent evidence suggests that changes in brain structure associated with alcohol abuse are compounded in individuals dually diagnosed with alcohol abuse and schizophrenia. To investigate the separate, and possibly interacting, effects of these diagnoses, an event-related brain potential (ERP) measure of auditory information processing (P50 sensory gating paradigm) and neuropsychological measures were administered to healthy control participants with either (1a) no history of alcohol abuse/dependence, or (1b) a remote history of alcohol abuse/dependence, and patients with schizophrenia with either (2a) no history of alcohol abuse/dependence, or (2b) a remote history of alcohol abuse/dependence. Schizophrenia was associated with impaired P50 sensory gating and poorer performance across neuropsychological scores compared to measurements in healthy control participants. Those with a positive alcohol history had impaired gating ratios in contrast to those with a negative alcohol history. There were additive effects of schizophrenia diagnosis and alcohol history for P50 sensory gating and for neuropsychological scores: attention, working memory, and behavioral inhibition. For executive attention and general memory there was an interaction, suggesting that the combination of schizophrenia and history of alcohol abuse results in greater impairment than that predicted by the presence of either diagnosis alone.

Linear CT-scan measurements in alcohol-dependent patients with and without delirium tremens

The aims of the present study were to examine whether chronic alcohol dependence and the development of delirium tremens are characterized by changes in linear CT measurements of brain liquor spaces and intracranial distances indicative of prefrontal atrophy, and frontal (sub)cortical or temporal (sub)cortical atrophy. Toward this end linear measurements were performed in 47 alcohol dependent patients with and without a history of delirium tremens and in 10 healthy volunteers using CT-scanning. The following linear measurements were calculated: (1) the Evans ratio; (2) the cella media index (CMI); (3) the maximum width of the third ventricle; (4) the maximum width of the fourth ventricle; (5) the maximum frontal subarachnoid space (MFSS); (6) the maximum width of the anterior interhemispheric fissure (MIF), and (7) the maximum width of the Sylvian fissure (MSF). The alcoholics were divided into subgroups according to the Münchner Alkoholismus Test (MALT) and the presence of delirium tremens. The MFSS of the alcohol-dependent patients was significantly larger than that of the controls. The MIF and MSF of high MALT scorers were significantly larger than those of low scorers and controls. Alcohol-dependent patients with a known history of delirium tremens had significantly larger MIF and MSF than did patients without delirium tremens and controls. The results suggest that alcohol dependence is characterized by prefrontal atrophy, and that frontal cortical and temporal (sub)cortical atrophy may be related to the development of delirium tremens.

Cognitive impairment and cerebral atrophy in "heavy drinkers"

1. Aim of the work was to verify the following three hypotheses in alcoholics: a) right hemisphere; b) diffuse brain deficit; c) anterior brain deficit, by means of a neuropsychological and a neuroradiological assessment. 2. 15 alcoholic right-hand male subjects and 15 matched controls were enrolled in the study. 3. Specifically designed neuropsychological testing was performed to investigate logical abilities, selective attention and memory. 4. Neurological investigation was performed by a standard CT scan to assess the degree and localization of brain damage. 5. Alcoholics performed worse than controls on some neuropsychological tests, i.e. Attention Matrices Test, Verbal Judgement Test, Forward Digit Span, Story Recall and Remote Memory Test. The analysis of variance adjusted by the attentional score showed no significant differences between alcoholics and controls. 6. Neuroradiological data showed a preeminent and a more frequent atrophy of the frontal region. 7. No correlations emerged between neuropsychological and neuroradiological data. 8. In conclusion, the hypothesis of anterior brain deficit seems to be confirmed by our study.

Alcoholism and dementia

This article reviews epidemiological, neurological, cognitive, and imaging data on alcohol-induced dementia. Recent studies indicate that "heavy alcohol use" (variously defined) is a contributing factor in 21-24% of cases of dementia. Research difficulties include lack of positive diagnostic criteria, few post-mortem studies, and no accepted pathological mechanism. Sulcal widening and ventricular enlargement (occasionally reversible) are the strongest findings in patients with alcohol-induced dementia. There is evidence for peripheral neuropathy, ataxia, sparing of language, and improved prognosis when patients with alcohol-induced dementia are compared to other dements. Case examples, etiologic theories, and recommendations for research, training, and clinical practice are included.

Neuropsychological changes during steady-state drug use, withdrawal and abstinence in primary benzodiazepine-dependent patients

Impairment on neuropsychological tests during steady-state drug use and withdrawal, and after discontinuation of benzodiazepines, was studied in primary benzodiazepine-dependent patients. One group of patients was tested before and the other group after the initiation of a gradual tapering-off of the drug, and both groups were tested approximately 1 year later. At the initial assessment, both groups of patients showed impairment on most of the tests of general intelligence and on several of the tests in the Halstead-Reitan battery, as well as on a test of nonverbal memory, in comparison with healthy controls. At follow-up the patient groups had reached the level of the control group. This study confirmed earlier observations of neuropsychological deficits in long-term benzodiazepine-using patients and demonstrated that these changes are at least partly reversible by discontinuing drug intake.

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.

The reversibility of alcoholic brain damage is not due to rehydration: a CT study

Alcoholic brain damage is reversible when the patients are continually abstinent. An increase of brain water content was the putative explanation for this phenomenon. We tested the rehydration hypothesis using CT density measurements in 29 alcohol-dependent male inpatients. During a 5-week period of controlled abstinence, CT density measures did not decrease in any of the investigated regions of the brain as one would expect with an increase in brain water. Although the volumetry of the ventricular system and the subarachnoidal spaces revealed a significant reduction of CSF volume, we found a slight increase in CT density measures. Thus, our results are in contradiction to the rehydration hypothesis. Under discussion is whether neuronal plasticity might be the explanation of the reversibility of alcoholic brain damage in abstinent patients.

Computed tomography of the brain, hepatotoxic drugs and high alcohol consumption in male alcoholic patients and a random sample from the general male population

Computed tomography (CT) of the brain was performed in a random sample of a total of 195 men and 211 male alcoholic patients admitted for the first time during a period of two years from the same geographically limited area of Greater Stockholm as the sample. The same medical, social and neuroradiological methods were used for examination of the alcoholic inpatients as for the random controls. Laboratory tests were performed, including liver and pancreatic tests. Toxicological screening was performed and the consumption of hepatotoxic drugs was also investigated and the following were the types of drugs used: antiarrhythmics, antiepileptics, antiphlogistics, mixed analgesics, barbiturates, sulphonamides, benzodiazepines, clomethiazole and phenothiazine derivatives, all of which are metabolised by the liver. The group of male alcoholic inpatients and the random sample were then subdivided with respect to alcohol consumption and use of hepatotoxic drugs: Group IA, men from the random sample with low or moderate alcohol consumption and no use of hepatotoxic drugs; IB, men from the random sample with low or moderate alcohol consumption with use of hepatotoxic drugs; IIA, alcoholic inpatients with use of alcohol and no drugs; and IIB, alcoholic inpatients with use of alcohol and drugs. Group IIB was found to have a higher incidence of cortical and subcortical changes than group IA. Group IB had a higher incidence of subcortical changes than group IA, and they differed only in drug use. Groups IIB and IIA only differed in drug use, and IIB had a higher incidence of brain damage except for anterior horn index and wide cerebellar sulci indicating vermian atrophy. Significantly higher serum (S) levels of bilirubin, gamma-glutamyl transpeptidase (GGT), aspartate aminotransferase (ASAT), alanine amino-transferase (ALAT), creatine kinase (CK), lactate dehydrogenase (LD) and amylase were found in IIB. The results indicate that drug use influences the incidence of cortical and subcortical aberrations, except anterior horn index. It is concluded that the groups with alcohol abuse who used hepatotoxic drugs showed a picture of cortical changes (wide transport sulci and clear-cut or high-grade cortical changes) and also of subcortical aberrations, expressed as an increased widening of the third ventricle.

Computerized tomographic study on the brain of patients with alcohol dependence

One hundred ten patients with alcohol dependence and 56 psychiatric patients with either senile dementia, amphetamine psychosis, epilepsy or chronic schizophrenia were investigated with a CT scan of the brain. The maximum width of the 3rd ventricle was measured, and the presence/absence of enlargement of the lateral ventricle and of atrophy of the frontal lobe was determined independently by 3 physicians. The width of the 3rd ventricle in alcoholic and the other patients examined was gradually enlarged with aging, and the width in these patients was significantly larger than that in the age-matched control patients who were selected from the patients with amphetamine psychosis, epilepsy or schizophrenia. The enlargement of the lateral ventricles observed in the alcoholic patients always accompanied the enlargement of the 3rd ventricle, but not vice versa. The alcoholic patients with frontal lobe atrophy showed a higher incidence of withdrawal delirium than the patients without atrophy. These findings suggest that the chronic intake of alcohol might affect primarily the area around the 3rd ventricle, resulting in enlargement of this ventricle and consequential enlargement of the lateral ventricles and also that the alcoholic patients with frontal lobe atrophy could have a high risk for a manifestation of alcoholic withdrawal delirium.

Cortical and diencephalic lesions in Korsakoff's syndrome: a clinical and CT scan study

Twenty-five male alcoholic Korsakoff patients were compared with age and sex-matched non-Korsakoff chronic alcoholics and healthy volunteers on clinical and CT brain scan parameters. The scans were assessed by planimetry, visual grading procedures and computerized analysis. Reliable measures of third ventricular size were developed. The Korsakoff patients had wider third ventricles, larger lateral ventricles and wider interhemispheric fissures than the comparison groups; but sulcal and Sylvian fissure widths were equivalent in Korsakoff and non-Korsakoff alcoholics. The results suggest that, in addition to their well-established diencephalic lesions, many Korsakoff patients have sustained widespread cerebral damage. Shrinkage in the frontal brain regions appears to be especially pronounced. The implications for a dual aetiology of alcoholic Korsakoff's syndrome involving thiamine deficiency and features associated with alcoholism, probably direct alcohol neurotoxicity, are discussed.

Pattern reversal visual evoked potential among men at risk for alcoholism

The biological sons of male alcoholics, deemed to be at high risk (HR) for the development of alcoholism, were compared to control males, aged 18 to 21, using measures of the visual evoked potential elicited by checkerboard pattern reversal. Overall, the HR and control groups were not distinguished on the basis of visual evoked potential measures acquired from the occipital scalp region; however, when comparisons were restricted to right-handed subjects, the HR subjects showed more symmetry in a positive component with approximate latency of 242 ms compared with control subjects. The results are discussed in relation to hemispheric differences and alcoholism.

Cerebral atrophy in younger persons: a comparative study between clinical examinations and computed tomography

Eighty-nine patients, all below the age of 50 and under suspicion of dementia underwent computed tomography. The degree of cerebral atrophy was visually estimated and also calculated using different ventricular diameters and the mean width of four cortical sulci. The degree of dementia was evaluated by a neurological specialist. No correlation between internal atrophy and the degree of dementia was found. In spite of a significant correlation between external atrophy and the degree of dementia, there was such overlap and underestimation that the value of computed tomography in quantifying atrophy in younger persons is very limited. In none of the patients did computed tomography disclose any organic cause of dementia.

Cerebral atrophy and slow wave sleep of abstinent chronic alcoholics

Although a considerable decrease of slow wave sleep (SWS) has been observed in abstinent chronic alcoholics, the under-lying mechanism is still obscure. In the present study CT scans and polysomnographic recording were repeatedly conducted in nine chronic alcoholics. SWS was remarkably reduced in all the patients, but it was slightly restored in six patients on the 6th month after abstinence. On the other hand, enlargement was observed in the cortical sulci, cerebral fissures and ventricles in these patients. The enlargement of the cortical sulci was improved in five patients, and four of the patients showed increase of SWS. Although enlargement of the cerebral fissures and ventricles was improved in a few patients, in most of the patients who showed improvement in the cortical sulci SWS was increased. The results indicate that the decrease in SWS in abstinent alcoholics may have resulted from the atrophy of the cerebral cortex.

[Is the increase in brain volume of abstinent alcoholics a sequela of rehydration?]

A group of 30 alcoholics as identified using the MALT score were examined both within the first 36 h of alcohol withdrawal and then again at the end of a 10-day treatment in hospital. We looked for clinical signs of dehydration, water and electrolyte imbalance, and concentration of steroid metabolites in the urine. Cranial computed tomography was also performed twice, again at the beginning and end of the 10-day period. The size of cerebrospinal fluid spaces was calculated through measuring the frontal interhemisphere distance, the width of cortical sulci, the ventricle III diameter, the Cella media index and also the number of vermal sulci. All patients had a brain atrophy which did not disappear within the 10 days. The neuroradiological parameters remained completely unchanged in the control examination. However, the laboratory parameters of the internal milieu had normalized. Therefore, it is submitted that the shrinkage of the brain of alcoholics cannot be due to a reversible intra- or extracellulary dehydration. There was also no proof of a hormonal cause for the brain shrinkage. As a consequence other etiological factors gain importance, such as malnutrition or a toxic alcohol effect.

The contributions of sex and drinking history to the CT brain scan changes in alcoholics

Consecutive series of male and female alcoholics, Alcoholic Anonymous (AA) members and controls were examined by interview and with a CT brain scan. Male controls were shown to have larger CT brain parameters than healthy females of the same age. Female alcoholics revealed equivalent CT scan abnormalities, apart from less sulcal widening, after a markedly shorter drinking history and at a lower estimated peak alcohol consumption than male alcoholics. The CT scan findings persisted after accounting for body weight and after matching for age and length of drinking history. The CT scan parameters of female AA members approached control values more completely and after briefer abstinence than did those of male AA members. Methodological problems and sex differences in selection and other processes are discussed. The findings are consistent with sex differences in the vulnerability of the brain to alcohol toxicity, and in its recovery with abstinence.

Computerized tomographic scan assessment of alcoholic brain damage and its potential reversibility

The assessment of alcoholic brain damage by computerized tomographic (CT) scanning is reviewed and discussed. Alcoholics showed greater cerebral atrophy than aged-matched neurological controls. Supratentorial atrophy measurements correlated significantly with some neurobehavioral assessment measures. The cerebral atrophy reversed in some subjects with maintained abstinence. Computerized assessment of cerebral spinal fluid volume (cerebral atrophy) and mean cerebral density showed decreased cerebral spinal fluid volume and increased cerebral density with maintained abstinence over 4 weeks in a group of 20 alcoholics. CT cerebellar measurements demonstrated atrophy in many subjects, but these measurements did not correlate with measures of ataxia, cognitive impairment, supratentorial atrophy measurements, or age. An example of a magnetic resonance imaging scan of an alcoholic is given. Its advantages in avoiding bony artifact for posterior fossa atrophy estimations and its potential for in vivo description and localization of central nervous system metabolic abnormalities in alcoholism are discussed.

The clinical versus radiological diagnosis of alcoholic cerebellar degeneration

We report the clinical characteristics of 65 patients with alcoholic cerebellar degeneration as verified by computerized tomography of the brain. Thirty-two patients (49%) had clear clinical signs of the disease such as broad-based staggering gait, impaired heel-to-toe walking, terminal oscillations in heel-knee test and slow (3/s) leg tremor. These signs were virtually absent in 33 patients (51%) who, nevertheless, had radiological signs of cerebellar degeneration. Traumatic brain injuries were more frequent in those patients who had both clinical and radiological signs of alcoholic cerebellar degeneration. Furthermore, this group showed longer periods of heavy drinking, more severe cerebral atrophy and more profound neuropsychological impairment than a control group of 92 alcoholics with neither clinical nor radiological signs of cerebellar disease. We conclude that careful clinical neurological examination is needed to diagnose alcoholic cerebellar degeneration which is apparently a more common disease than first realized. Subclinical cases can be diagnosed with the help of computerized tomography of the brain.

Cerebral dysfunction in alcoholism related to mortality and long term social adjustment

All 1312 first-admitted alcoholics at the Department of Psychiatry, University Hospital, Lund (120 women) during 1949-1969 were followed until December 31, 1980. There were 537 deaths. All patients had been rated at discharge with a multidimensional rating scale including signs of cerebral dysfunction. Thirty-three per cent of the total patient group had signs of cerebral dysfunction, increasing with age up to 64% in those over 50 years. Men younger than 50 years with brain dysfunction had a higher mortality caused by alcohol-related physical disorders in relationship to violent deaths compared with the others. The main finding in those over the age of 50 was the increased number of deaths caused by circulatory disorder in the brain dysfunction group. The social prognosis was similar in all groups. It is suggested that a continuous and heavy drinking pattern in the young dysfunctional group and an accelerated aging in the old dysfunctional group could explain the differences found.

CT demonstration of the early effects of alcohol on the brain

CT evidence of brain damage has been sought in subjects consuming alcohol between 10 g/day to over 200 g/day. Dietary contributing factors have been evaluated. The level of atrophy (shrinkage) has been correlated with intellectual performance. To establish a relationship between alcohol intake and brain structure and function, re-examination of subjects over a 6- to 12-month period of abstinence has been undertaken to examine any reversibility features. A record of liver function showed that brain damage always precedes liver damage. Subjects were re-examined a second time, who had initially abstained for six months and then had returned either to their original level of consumption or to one that was somewhat reduced. A regression in initial improvement was considered evidence of reversible brain damage that had originally been related to alcohol. The threshold consumption for CT damage was 40 g/day, but the level of CT atrophy at which cognitive dysfunction appeared has still to be established.

Cognitive deficits and morphological cerebral changes in a random sample of social drinkers

A random sample of 200 men and 200 women taken from the general population as well as subsamples of 31 male and 17 female excessive social drinkers were investigated with neuropsychological tests and computed tomography of the brain. Relatively high alcohol intake per drinking occasion did not give evidence of cognitive deficits or morphological cerebral changes. However, in males, mild cognitive deficits and morphological cerebral changes as a result of high recent alcohol intake, particularly during the 24-hr period prior to the investigation, were observed. When excluding acute effects of recent alcohol intake, mild cognitive deficits but not morphological cerebral changes that are apparently due to long-term excessive social drinking were observed in males. In females there was no association between the drinking variables and cognitive deficits or morphological cerebral changes, probably due to their less advanced drinking habits. It is suggested that future risk evaluations and estimations of safe alcohol intake should take into consideration the potential risk for brain damage due to excessive social drinking. However, it is premature to make any definite statements about safe alcohol intake and the risk for brain damage in social drinkers from the general population.

Peripheral neuropathy, cerebral atrophy, and intellectual impairment in chronic alcoholics

Peripheral neuropathy, cerebral atrophy, and intellectual impairment was investigated in 46 males with alcoholic nervous system damage. An overall correlation was found between peripheral neuropathy and cerebral atrophy and between several of the individual neurophysiological and neuroradiological variables examined. There was also a correlation between cerebral atrophy and intellectual impairment. The findings support the view that alcohol in itself is toxic to central and peripheral nervous tissues, although a dose-response dependence could not be established.

Increased cerebral ventricular volume in monozygotic twins discordant for alcoholism

21 pairs of monozygotic twins discordant for alcoholism and heavy drinking were examined by computerised tomography. Brain and ventricular volumes were calculated by the use of a semiautomated method with the rater blind to twinship and drinking history. 11 severely dependent alcoholics had larger ventricular volumes and ventricle/brain ratios than did their normal cotwins. These changes correlated best with the length of time the alcoholic twin had been drinking eight centilitres pure alcohol, equivalent to a bottle of wine, a day.

The alcoholic brain: CT scan and psychological findings

One hundred male alcoholics without overt clinical signs of brain damage were interviewed, psychologically tested and scanned by means of a CT 1010 EMI scanner. Fifty age-matched controls, lifelong abstainers or light drinkers, were used for comparison. Fifty-six alcoholics from the initial sample were followed up after periods varying from 30 to 152 weeks, and radiological changes during the follow-up were assessed. The main results of the study can be summarized as follows: (1) All CT scan indices were significantly different in alcoholics and controls. Alcoholics had larger ventricles, wider cerebral sulci and wider Sylvian and interhemispheric fissures. Cerebellar sulci were visible only in alcoholics. These differences were greater for older alcoholics and controls, but were also present in the younger subjects. (2) In the alcoholic group the size of the ventricular system, and the width of the sulci, Sylvian and interhemispheric fissures were positively and significantly correlated with age. The duration of the drinking history and the age of onset were not significantly correlated with CT scan indices. (3) In those alcoholics whose age was greater than the mean for the whole group, the size of the ventricular system and width of the Sylvian fissure were significantly and negatively correlated with the duration of abstinence prior to scanning. (4) Other features such as decreased tolerance, a positive family history of alcoholism and 'social decline' were not significantly related to the severity of CT scan abnormalities. (5) When the effects of age and premorbid intelligence were controlled, alcoholics showed significant cognitive impairment when compared with controls. The differences in the scores of psychological tests and CT scan indices were greater between alcoholics and controls of high IQ than between those of low IQ. This discrepancy is likely to be due to a selection bias. (6) No significant correlations were found between the degree of cognitive impairment and clinical features. The size of the ventricular system was positively and significantly correlated with the discrepancy between immediate and delayed recall of verbal material. There were no other significant correlations between cognitive impairment and CT scan indices. (7) Those subjects who had remained abstinent during the follow-up period, when considered as a group, showed a significant reduction in the size of the ventricular system. When cortical indices and V/B ratio were combined, patients whose scans had improved at follow-up differed from the rest with regard to the length of abstinence prior to re-scanning.

Examination of alcoholics by computed tomographic (CT) scans: a critical review

Neuroradiological studies have consistently demonstrated that alcoholics have morphological abnormalities of cortical, ventricular, and cerebellar structures suggesting brain atrophy. This atrophy is weakly correlated with impaired psychological test performance. Because brain atrophy and intellectual impairment can also be found in normal aging it is necessary to compare alcoholics with age-matched control subjects. It is currently unknown if alcohol-associated brain atrophy and intellectual impairment are the result of conditions preceding alcohol consumption or conditions only indirectly related such as head trauma or other associated diseases. Direct alcohol toxicity would be supported by quantitative alcohol-atrophy dose-response relationships and by a partial reversal of atrophy and functional impairment following abstinence from alcohol. Because of methodological difficulties inherent in neuroradiological research, data on the exact pathogenesis of abnormalities in alcoholics have not been produced. The design of such studies can be improved to increase the probability that the causes of brain atrophy will be elucidated.