Computed tomography and aging of the brain

Prevalence and clinical correlations of olfactory recess dilatation in MRI studies of the feline brain

The ability to differentiate clinical ventriculomegaly from incidental ventricular enlargement remains a challenge in veterinary radiology. Dilatation of one or both olfactory lobe recesses is occasionally seen on MRI of the brain in otherwise normal cats. The purpose of this study was therefore to determine the prevalence of this finding within a population of neurologically normal and neurologically abnormal cats, and to investigate associations with signalment, clinical and neurological examination findings, and MRI features. An observational retrospective cohort study was performed, and archived records were searched for cats that had undergone MRI of the head, including the olfactory lobes. Medical data and MRI parameters were recorded. One hundred fifty-one cats were included, with olfactory recess dilatation present in 56 cats. In 16 neurologically normal cats, olfactory recess dilatation was the only MRI finding. Olfactory recess dilatation was not associated with age, sex, breed, or with the presence of nasal disease. A significant association was found between generalized ventriculomegaly (P = 0.001) and the presence of CSF abnormalities (P = 0.036). Eleven percent of our cohort (16/151) demonstrated olfactory recess dilatation in the absence of other neurological or structural intracranial disease, suggesting that this may be seen as a normal variation in some cats.

Computed Tomography of the Brain in Cases with Venous Vasculitis Compared with an Age-Matched Reference Group

Patients with a particular, steroid-sensitive headache and often characteristic pathology at orbital phlebography, have been suggested to suffer from venous vasculitis. Fifty such patients were examined with computed tomography (CT) of the brain. The findings were compared with those of an age-matched reference group selected at random to represent normal subjects. The CT examinations were analyzed with respect to size of lateral ventricles and signs of atrophy. In both groups, there was a significant increase of atrophy with age. There was also a significantly higher degree of atrophy in the patient group as compared with the reference group. The findings indicate that the supposedly underlying venous vasculitis is related to early aging and atrophy of the brain.

Evaluation of total cerebral blood flow volume in cerebral atrophy

The goal of our study is to determine total cerebral blood flow volume (tCBFV) via extracranial Doppler ultrasound and to investigate its value in the differential diagnosis of dementia. Twenty-eight outpatients with cerebral atrophy confirmed by cranial computed tomography were enrolled into the study. Nine patients with Alzheimer's disease (AD) and nine patients with vascular dementia (VaD) based on neuropsychologic test and imaging findings, as well as 10 neurologically normal elderly subjects underwent Doppler sonographic examination of extracranial internal carotid artery (ICA) and vertebral artery (VA). Angle corrected time averaged flow velocity and cross-sectional areas of vessels have been measured. Flow volumes and tCBFV have been calculated. The measures of tCBFV, anterior CBFV (aCBFV), right CBFV (rCBFV) and right ICA flow volume were significantly lower in patients with dementia. The amounts of tCBFV, aCBFV, rCBFV and right ICA flow volume have been found to be low in AD and VaD patients compared with normal elderly group. Of all parameters measured for AD and VaD, no significant difference was found except Mini-Mental State Examination (MMSE) scores. To the best of our knowledge, this is the first reporting the CBF measurements using Doppler ultrasound of extracranial ICA and VA in the differential diagnosis of dementia in cerebral atrophy. The tCBFV, aCBFV, rCBFV and right ICA flow volumes and MMSE scores are significant in the diagnosis of dementia, whereas only MMSE scores are significant in the differential diagnosis of AD and VaD.

MRI parameters of Alzheimer's disease in an Arab population of Wadi Ara, Israel

Magnetic resonance imaging (MRI) findings are reported from 15 individuals in an Arab-Israeli community who were diagnosed with Alzheimer's disease (AD). The quantitative parameters that were used for MRI analyses included gradings (0-3) and linear measurements of different brain structures. Generalized tissue loss was assessed by combined measurements of the ventricles (ventricular score, VS) and sulcal grading and width (SG, SW, respectively). Loss of brain tissue in specific regions of interest, eg, temporal lobes, basal ganglia, and midbrain, was evaluated by precise measurements. We observed abnormal tissue characteristics, expressed as high intensity foci in white matter on T2W sequences, as well as tissue loss, both generalized and focal. Most notable were changes involving the head of the caudate nuclei, the midbrain, and to a lesser degree, medial temporal structures.

Changes of Magnetic Resonance Imaging on the Brain in Beagle Dogs with Aging

Age-associated changes of magnetic resonance imaging (MRI) on the brain were evaluated in 19 beagle dogs aged from 8-month- to 16-year-old. A significant correlation of the volume of lateral ventricle space was observed in the dogs with age advanced, however, no correlation was found between hippocampus size and the aging. The hypo-intensity areas on T2-weighted MRI were detected in globus pallidus and substantia nigra with a significant correlation of both intensity ratios to lateral ventricle with age advanced. These areas were coincided with the accumulation of iron in the slice of the brain with Perls' staining. In addition, hyper-intensity area, suggesting perivascular demyelination with fluid-filled space, was also observed in white matter surrounding the lateral ventricle on T2-weighted MRI. These results suggested that age-associated changes of T2-weighted MRI were developed in the dog brain, especially in globus pallidus, substantia nigra, and white matter surrounding lateral ventricle, like as those reported in the human brain.

Altered circadian cortisol secretion in Alzheimer's disease: clinical and neuroradiological aspects

We determined circadian salivary cortisol levels in 18 outpatients affected by probable Alzheimer's disease (AD) and looked for a possible correlation with both cognitive impairment and brain CT scan findings. The diagnosis of probable AD was made according to the NINCDS-ADRDA criteria. The severity of cognitive impairment was quantified using the Mini Mental State Examination (MMSE) and the Global Deterioration Scale (GDS). Cortisol levels were measured on saliva samples collected at 08:00 AM and 08:00 PM. For each sample, a duplicate cortisol measurement was performed on 50 microl of saliva by means of a modified commercial radioimmunoassay kit. At the same time, 11 of the 18 AD patients enrolled also underwent a brain CT scan to estimate cerebral atrophy by using linear indexes. The mean value of cortisol levels was significantly higher in AD patients than in controls at both the morning and the evening measurements, and the circadian fluctuation of cortisol was less marked in AD patients than in controls, although this difference did not reach statistical significance. Morning cortisol levels were significantly correlated to both the MMSE and the GDS scores. A significant correlation was also found between morning cortisol levels and all the cerebral atrophy indexes. By contrast, no correlation was observed between evening cortisol levels or cortisol circadian fluctuations and either cognitive impairment or cerebral atrophy. In conclusion, despite the potential biases deriving from the small sample and the limitations of the CT scan study, our results suggest that, in AD patients, hypercortisolemia is correlated with severity of the disease.

Clock drawing test: correlation with linear measurements of CT studies in demented patients

OBJECTIVES

To investigate a presumed correlation between clock drawing ratings and linear measurements of computerized tomography (CT) studies in demented patients.

DESIGN

Blinded evaluations of clock drawing tests and CT studies of elderly dementia patients were conducted by a geriatric psychiatrist and a neuroradiologist.

SUBJECTS

Fifty-one community-dwelling elderly subjects meeting the criteria for DSM-IV diagnosis of dementia (Alzheimer's type dementia: N=31; vascular dementia: N=15; "mixed" type dementia: N=5).

MATERIALS

Mini-Mental State Examination (MMSE), Cambridge Cognitive Examination (CAMCOG), Clinical Dementia Rating (CDR). CAMCOG derived scored clock drawings were evaluated using adaptations of Shulman et al.'s and Freedman et al.'s methods. CT studies were evaluated using six different linear measurements of brain atrophy described in the literature.

RESULTS

Of the CT linear measurements, only the Cerebro-Ventricular Index-2 (CVI-2; bicaudate index) significantly correlated with clock drawing ratings (CAMCOG's clock r=-0.407, p=0.003; Shulman's method r=0.357, p=0.01, Freedman's method r=-0.413, p=0.003) in the dementia group. There was no significant correlation between CVI-2 with demographic (age), cognitive (MMSE, CAMCOG) and clinical (duration of illness, CDR) ratings. Alzheimer's patients generally maintained a significant correlation between CVI-2 and clock drawings, but vascular dementia patients did not; CVI-2 also correlated significantly with the Praxis subtest of the CAMCOG in dementia and Alzheimer's patients but not in the vascular dementia group. Similarly, multiple stepwise regression analysis showed that only CVI-2 but not the other radiological measures studied, was selected as the significant variable to correlated with clock drawing test ratings in the dementia group and Alzheimer's patients. Partial correlation analysis controlling for demographic and clinical variables shows that controlled variables had no significant effect on the relationship between clock drawing ratings and CVI-2.

CONCLUSION

A single and easy to perform measure of caudate atrophy correlates specifically and consistently with impairments revealed in the clock drawing test and with a Praxis subtest, suggesting possible caudate involvement with clock drawings in dementia in general and of the Alzheimer's type in particular.

Regional HmPAO SPECT and CT measurements in the diagnosis of Alzheimer's disease

BACKGROUND

This study investigated the hypothesis that the combination of regional CT brain atrophy measurements and semiquantitative SPECT regional blood flow ratios could produce a diagnostic test for Alzheimer's disease (AD) with an accuracy comparable to that achieved with the present clinical gold standard of the NINCDS-ADRDA criteria.

METHODS

Single proton emission computed tomography (SPECT) and CT head scans were performed on 122 subjects referred an UBC Alzheimer clinic and diagnosed as either 'not demented' (ND-37) or 'possible/probable AD' (AD-85) by the NINCDS-ADRDA criteria. Stepwise discriminant analysis (SDA) was performed on the bilateral SPECT regions of interest and compared to bilateral CT qualitative/quantitative assessment in the frontal, parietal and temporal lobes to determine which were most accurate at ND/AD distinction. Receiver operating curves (ROC) were then constructed for these variables individually and for their combined discriminant function.

RESULTS

The left temporal qualitative cortical atrophy score (CT) and left temporal perfusion ratio (SPECT) were selected in the SDA. The combined discriminant function was more specific at AD/ND distinction than either of CT or SPECT alone. The accuracy of AD/ND distinction with the combined discriminant function was below that achieved by clinical diagnosis according to the NINCDS-ADRDA criteria and was not significantly different from that achieved with SPECT or CT alone as defined by ROC curve analysis.

CONCLUSION

The measurements of left temporal cortical atrophy and regional cerebral blood flow were most indicative of AD; however they lacked the sensitivity and specificity to recommend their use as a diagnostic test for AD.

Infraputaminal 'lacunes'. Clinical and pathological correlations

BACKGROUND AND PURPOSE

Single, oval lesions greater than 5 mm in diameter lying inferior to the lateral putamen (infraputaminal lacunes [IPLs]) seen on CT or MR images are commonly reported as lacunar infarcts. To determine the clinical relevance and underlying pathology of IPLs, we evaluated the imaging appearances, clinical features, vascular risk factors, and histopathology in patients with IPLs.

METHODS

Consecutive MR scans were reviewed for the presence of IPLs. Serial patients seen in routine clinical practice with IPLs were also included. Vascular risk factors were obtained from a prescan questionnaire. Histology and microangiography were performed on postmortem material. A MEDLINE search for putaminal infarcts was performed to look for imaging lesions typical of IPLs.

RESULTS

Three of 100 serial MR scans had IPLs (3%). Nine other patients with in vivo (7) or postmortem (2) MR scans had IPLs. No neurological symptoms could be related to the IPLs. There were no differences in age, hypertension, diabetes, or presence of cortical enlarged perivascular spaces (EPVSs) between patients with and without IPLs. Unlike infarcts, IPLs were isointense with the cerebrospinal fluid on proton density MR sequences. Histological correlation of three MR scans showed IPLs to be a single large EPVS, situated lateral to the anterior commissure. IPLs were located at a point where multiple lenticulostriates turn sharply dorsally. An IPL was the probable cause of the apparent infarct in six publications from peer-reviewed literature that linked different clinical signs to putaminal infarct.

CONCLUSIONS

IPLs are EPVSs that can be differentiated from infarcts on proton density MR images.

MR imaging of ventriculomegaly--a qualitative and quantitative comparison of communicating hydrocephalus, central atrophy, and normal studies

Both communicating hydrocephalus and central atrophy cause ventricular dilatation. However, patients with hydrocephalus may require treatment. The aim of this study was to assess qualitatively and quantitatively the efficacy of MR imaging in the differentiation of communicating hydrocephalus from central atrophy. The midsagittal T1-weighted MR images of 33 patients with communicating hydrocephalus, 31 patients with central atrophy, and 23 normal subjects were evaluated qualitatively and quantitatively. This included configuration of the aqueduct; area of the septum pellucidum, third ventricle, and fourth ventricle; and morphology of the corpus callosum. Distal dilatation of the aqueduct was detected in 33.3% of patients with communicating hydrocephalus and in none of those with central atrophy. The corpus callosum was elevated in patients with communicating hydrocephalus when compared with that in patients with central atrophy. In conclusion, an analysis of midsagittal T1-weighted images has identified useful qualitative and quantitative criteria in the differentiation of communicating hydrocephalus from central atrophy. The configuration of the aqueduct with funneling at the fourth ventricular end strongly suggests the presence of communicating hydrocephalus rather than central atrophy alone.

Pontine ischemic rarefaction

To investigate apparently asymptomatic, bilateral symmetrical predominantly pontine hyperintensities (PHI) on magnetic resonance imaging (MRI) scans in elderly patients, we examined the pons histopathologically in two brains of elderly hypertensives with PHI, and in three without PHI, on postmortem MRI scans. We also reviewed 85 serial in vivo MRI scans of patients over 60 and compared scan findings, vascular risk factors, and clinical symptoms between patients with PHI and a control group. A subcortical arteriosclerotic encephalopathy (SAE)-like pathology was present in the pons in only the two autopsy brains with PHI and corresponded with the location of PHI on the postmortem MRI scans and with the most frequent sites of PHI on in vivo scans. SAE also involved the hemispheric white matter in one of the autopsy brains. Five of 16 (31%) patients with, and 4 of 69 (6%) without, PHI on in vivo MRI scans had marked periventricular hyperintensity (PVHI) compatible with SAE (p = 0.01). We conclude that an SAE-like pathology may be seen in the pons in elderly hypertensives and this pathology is probably the cause of PHI seen on MRI scans of patients over 60 years of age.

A critique of instruments and methods to detect, diagnose, and rate delirium

This document reviews existing instruments for evaluation of delirium. Instruments have been grouped into four categories: tests that screen for cognitive impairment, delirium diagnostic instruments, delirium-specific numerical rating scales, and laboratory and paraclinical exams. Analysis of instruments was based on comparison of their psychometric properties as well as subjective judgment. Guidelines are suggested for choosing the appropriate instrument according to the type of clinical evaluation or delirium research envisaged. Important factors in choosing an instrument, besides the appropriateness of its psychometric characteristics, include administration time constraints, level of rater expertise, and patient capabilities. By familiarizing investigators with the variety of evaluation instruments available, this work should permit more appropriate instrument selection in future studies on delirium.

MRI volumetric studies in Alzheimer's disease: relationship to clinical and neuropsychological variables

The authors studied 34 subjects with probable dementia of the Alzheimer type (DAT) and 28 healthy, age-matched control subjects, using a 1.5-tesla GE MRI scanner. Absolute volumes of ventricular and sulcal cerebrospinal fluid spaces and volumes, corrected for total intracranial volume, were significantly higher (P < 0.01) in the DAT group, compared to the control group. Right-left measures of hemispheric structural asymmetry were greater in the DAT group, whereas aging alone influenced brain structure in the control group. Also, in the DAT group, certain volumetric measures were significantly correlated with specific clinical indicators of severity of illness and some neuropsychological indices. These data demonstrate widespread structural abnormalities in relatively early DAT and a relationship between brain structure and some measures of cognitive dysfunction.

The usefulness of CT scanning in diagnosing dementia of the Alzheimer type

In order to determine the usefulness of Computerized Tomography (CT) scanning in making a diagnosis of dementia of the Alzheimer type, a group of patients diagnosed by NINCDS-ADRDA criteria (n = 22) were compared to a group of normal subjects (n = 49) using certain defined linear CT scan measurements. These measurements included specific measurements of the temporal lobes (temporal horns). Subjects were classified correctly 91.5% of the time with a high degree of probability. A diagnostic equation is presented which will allow testing of these methods in a prospective fashion.

Neuroanatomic substrates of depression in the elderly

The causes of depression in the elderly are poorly understood. The concept that psychological and social factors are the primary contributors to the occurrence of depression in later life, though intuitively appealing, is not supported by available evidence. In addition, genetic factors are less significant in patients presenting with depression for the first time in later life. In this article, the following hypotheses are examined: (1) the aging process facilitates emergence of depression in later life; (2) cerebrovascular pathology plays a role in the etiology of depression in the elderly; and (3) the site and location of changes in the brain provide a basis for understanding neuroanatomic substrates of depression in the elderly. The role of the basal ganglia and different basal ganglia circuits in the pathophysiology of depression is discussed. The clinical significance of the findings of structural changes in the brain are also discussed.

Encephalopathy in ifosfamide-treated patients

Acute encephalopathy following treatment with ifosfamide and mesna was observed in 5 (4 women and 1 men) of 28 patients (17.8%), with advanced sarcoma, lymphoma or ovarian carcinoma. This appeared within 2 to 7 days following the first dose of ifosfamide treatment, and included mental status changes, urinary incontinence, weakness, seizure activity, altered consciousness and psychiatric manifestations. Three cases were fatal, while two patients recovered completely. Brain CT and morphometric studies were normal in all the patients. Associated findings were myelosuppression, renal failure and electrolyte alterations.

Diabetes mellitus and brain atrophy: a computed tomography study in an elderly population

Previous studies have suggested that noninsulin dependent diabetes mellitus (NIDDM) could lead to learning and memory deficits. We studied cognitive performance and computed tomography (CT) findings of the brain in elderly subjects with drug treated NIDDM (n = 12), with diet treated NIDDM (n = 13), and in nondiabetic individuals (ND, n = 59). The cognitive performance (orientation and up-to-date knowledge, praxic functions, understanding of speech, expressive speech, memory, general reasoning) did not differ between the groups. The drug treated diabetics had more pronounced central temporal atrophy compared to that in the ND subjects as evidenced by wider right temporal horn (ANCOVA adjusted for age, p = 0.011). The drug treated diabetics (all women) also had wider frontal horns than did the ND women. The CT measures of diet treated diabetics were comparable with those of the ND group. The fasting glucose level was positively correlated with the width of the right temporal horn but not with other CT measures in diabetic subjects. The results suggest that NIDDM and poor glucose control may carry a risk for accelerated brain atrophy in the elderly.

Morphometry, histopathology, and tomography of cerebral atrophy in the acquired immunodeficiency syndrome

Patients with the acquired immunodeficiency syndrome (AIDS) commonly display evidence of gross cerebral atrophy, but its true incidence and pathophysiology in the general AIDS population are unknown. In this study, we measured cerebrospinal fluid (CSF) spaces in 64 consecutively autopsied patients with AIDS, compared them with age-matched non-AIDS subjects, and correlated them with the microscopic neuropathology at autopsy. Thirty-seven of the patients with AIDS (58%) had a CSF space index greater than two standard deviations above the mean of the age-matched control subjects. CSF spaces were expanded the most in frontal and temporal lobes; ventricular spaces were expanded more than sulcal spaces. Regression analysis between age and the measured CSF indexes showed that practically none of the deviation in patients with AIDS could be explained by age-related atrophy. Patients with atrophy were much more likely to have human immunodeficiency virus type 1-associated histopathological changes in their brains, but the relationships were too weak to establish the microscopic cause of the atrophy. Measurement of CSF spaces in antemortem computed tomographic (CT) scans from 47 of the patients with AIDS revealed the same regional pattern of brain wasting. CT diagnosis of cerebral atrophy was strongly concordant with the postmortem diagnosis, but its severity was diagnosed slightly more conservatively at autopsy. Thus, quantitative analysis of CSF spaces in a robust sampling of patients with AIDS confirms that cerebral atrophy is a sensitive, common, and frequently subtle indication of central nervous system human immunodeficiency virus type 1 infection that may occur independently from any single specific microscopic abnormality. Its presence, severity, and regional pattern are detected with reasonable consistency using CT scanning.

Does the shunt opening pressure influence the effect of shunt surgery in normal pressure hydrocephalus?

Thirteen patients with normal pressure hydrocephalus were operated upon with an externally maneuverable shunt system (Sophy SU8) in order to investigate its influence on clinical outcome, intracranial pressure and cranial CT parameters. The opening pressure was set at high at surgery and lowered stepwise at intervals of three months to medium and low. The clinical condition, intracranial pressure and cranial CT parameters were examined at the end of the 3 months interval on each pressure level. The patients improved within the first 3 months inspite of an unchanged mean intracranial pressure and remained in a stable clinical condition during the rest of the study period. The intracranial pressure was significantly reduced at 9 months. The ventricular index, Evans index, temporal horn and third ventricle width were reduced 3 months post-operatively and did not change significantly during the rest of the study. The pre-operative third ventricle width was correlated to high psychometric test results after shunt surgery. Reduction in ventricular index, Evans index and third ventricle width after surgery correlated to improvement in psychometric scoring. The clinical improvement after shunt surgery for normal pressure hydrocephalus is seen within 3 months and is independent of the adjusted valve pressure.

Evaluation of encephalic ventricular volume from the magnetic resonance imaging scans of thirty-eight human subjects

Accurate volume determination of the encephalic ventricles is of importance in several clinical conditions, including Alzheimer's presenile dementia, schizophrenia, and benign intracranial hypertension. Previous studies have investigated the accuracy with which magnetic resonance imaging (MRI) can be used in clinical practice to evaluate the encephalic ventricles. However, adequate evaluation of pathological conditions depends on a sufficient amount of morphometric data from normal subjects. To begin establishing this data base for "normal" subjects, we evaluated the MRI scans of 38 subjects found to have no apparent pathology and calculated the ventricular volume in each case by using methods previously developed in our laboratory. The results were then compared with published volumes determined from studies that used either ventricular casts or computerized tomographic scans. The average total ventricular volume for all 38 subjects was 17.4 cm3, while that for males was 16.3 cm3 and that for females was 18.0 cm3. A small but significant correlation was found between age of subject and ventricular volume, with ventricular size increasing with age.

Cortical atrophy and cognitive performance in infantile nephropathic cystinosis

A group of children and adolescents with infantile nephropathic cystinosis underwent cognitive testing and were examined for cortical atrophy using magnetic resonance imaging or computed tomography. Ten of 11 patients demonstrated cortical atrophy. A consistent pattern of lower cognitive performance was found in patients with greater atrophy; however, only the relationship between atrophy and short-term memory approached statistical significance. In addition, evidence for greater impairment of visual memory than of other cognitive functions was observed. This latter observation did not appear to be related to the degree of atrophy.

Cerebrospinal fluid levels of somatostatin, corticotropin-releasing hormone and corticotropin in alcoholism

Reduced brain and cerebrospinal fluid (CSF) levels of somatostatin, corticotropin-releasing hormone (CRH) and corticotropin (ACTH) have been reported among neuropsychiatric patients with cognitive dysfunction. Alcoholism is a disorder in which associated neuropsychiatric disorders occur. Therefore, we compared CSF levels of somatostatin, CRH and ACTH in alcoholics (n = 100) and normal controls (n = 30). There were no significant differences between the groups in concentrations of the 3 peptides. Moreover, there were no significant correlations between concentrations of the peptides in CSF and computed tomographic measures of the size of brain ventricles. There were, however, significant correlations between CSF concentrations of CRH and ACTH and between CSF concentrations of CRH and somatostatin in both the alcoholic and control groups.

An empirical model for analysing and interpreting ventricular measures

Given the abundant and, at times, contradictory studies of ventricular enlargement in neurological and psychiatric disorders, the current study was carried out to provide an empirical basis for analysing and interpreting these measures. A sample of CT scans on 100 control subject was drawn from the files of the University of British Columbia Department of Radiology and 19 measures of ventricular and head diameter or area were made. The interrelationships of these measures were then examined using factor analytic procedures. Three ventricular dimensions were found. To validate these three dimensions, the relationship of each with age was examined and then the age-corrected scores of seven clinical groups were compared on each of these dimensions. The magnitude of the relationship between these dimensions and age was impressive and each dimension contributed unique information regarding these age-related changes. Moreover, the analysis of the clinical groups suggested that differential patterns of ventricular change were present dependent upon the disease. These results are discussed with a view to integrating the findings of previous studies and planning future studies.

Volume determinations of the encephalic ventricles with CT and MRI

The volume of the encephalic ventricles was determined from magnetic resonance imaging (MRI) scans. Since there are many conditions in which the encephalic ventricles become enlarged such as Alzheimer's disease and hydrocephalus, accurate measurement of the ventricles provides a valuable and safe means of aiding the diagnosis of such conditions and also provides important follow-up information in affected patients. The objective was pursued in a three phase study. This paper presents the data obtained from the first phase. This first phase demonstrated the possibility of measuring fluid filled spaces by MRI in three phantom preparations (small, medium, and large "ventricles"). The results were compared with those obtained from computerized tomography (CT) scans of the same preparations. These volumetric calculations were done with the aid of a Calcomp 9,000 digital analyzer programmed to compensate for the scale factor and slice thickness of the images. The phantom study showed that the results obtained from the MRI scans were better than those obtained from the CT scans in measuring the volume of water-filled cavities (ventricles) in gelatin phantoms. The average percent difference between volumes obtained by an imaging procedure compared to the actual volume as determined by water displacement was 15.8% for CT scanning and a more impressive 8.3% for MRI.

Brain imaging techniques in the diagnosis of dementia

Various recently developed brain imaging techniques used to assist in the diagnosis of dementia are reviewed. The methods reviewed are x-ray computed tomography scan imaging, magnetic resonance imaging, positron emission tomography, and the older techniques of pneumoencephalography and radioisotope cisternography. It was concluded that while these techniques often offer excellent diagnostic information, none of them provides a definitive characteristic image for Alzheimer's disease.

Interferon-related mental deterioration and behavioral changes in patients with renal cell carcinoma

Five out of 38 patients (13%) with metastatic renal cell carcinoma had mental deterioration 3 weeks to 13 months after the start of treatment with recombinant interferon alpha-C. Metastatic spread to the brain, paraneoplastic effect of the tumor on the central nervous system and other causes of dementia were excluded. Computed tomography of the brain in these patients was normal and the width of the cerebral sulci and ventricles did not correlate with the severity of dementia. Specific patterns of atrophy were not seen. General deterioration, assessed by the change in Karnofsky performance status, was associated with dementia. The dementia may have been caused by a neurotoxic effect of interferon.

MRI parameters in multiple sclerosis patients

Magnetic resonance imaging (MRI) findings of 20 patients with clinically definite multiple sclerosis (MS) are presented. The studies were performed on a 0.5 Tesla magnet using spin-echo technique. Analysis of the MRI findings included detailed linear measurements of the ventricular and the subarachnoid spaces and reading of the intensity of the grey and white matter and intensity of the MS plaques. The plaques were sorted according to their number and size. The younger patients (20-40 years) had overall more plaques than the older ones (over 40 years). The small plaques were the most numerous and the large ones were the least common. Statistically significant association was found between the number of plaques and the cella media width. The intensity ratios between the non-plaque white matter/grey matter showed a significant correlation with the ventricular score. A significant negative correlation was found between the antero-posterior diameter of the spinal cord and the number of MS plaques in the brain. The plaque/white matter ratio had a significantly negative correlation with the cervical cord's width.

The role of clinical neuropsychology in the neurological diagnosis of Alzheimer's disease

This survey on the early diagnosis of Alzheimer's disease (AD) reinstates the role of clinical neuropsychology in describing the cognitive status of AD and its evolution. The role of clinical neuropsychology is restricted to the clinical diagnosis of organic mental deterioration and its contribution to the diagnosis of AD is separate from that of neurology and neuroradiology. The frequency of a single neuropsychological disturbance in early AD patients is illustrated by our own observations.

Acute confusional states in the elderly: a radiological evaluation

Computered tomography of the head was carried out on 35 patients who received a hospital diagnosis of delirium according to the DSM-III, and 25 controls without cognitive disturbance. There were no statistically significant differences in the mean age of the groups or in the cortical atrophy score as measured by the mean width of the four largest sulci in the three uppermost tomographic cuts. Instead, the delirious patients differed from the controls in the frontal horn and cella media indices, in the width of the third ventricle and Sylvian fissure at insula on the left side. There was also a significant excess of low attenuation, brain infarct-type areas in the delirious patients. The study confirms the marked predisposing role of the structural brain diseases (primary degenerative and multi-infarct type dementias, Parkinsonism) in the development of acute delirium in elderly patients.

A quantitative study of physiological cerebral atrophy with aging. A statistical analysis of the normal range

A new method of discriminating pathological cerebral atrophy from physiological atrophy during aging is reported. The authors advocate a pixel counting method using a minicomputer for the quantitative measurement of cerebral atrophy. Five hundred cases were studied with this quantitative method and the normal range of the physiological atrophy was determined statistically. In order to estimate the degree of cerebral atrophy easily, the conventional linear measurement methods were compared with the pixel counting method using multivariant analysis, and a simple formula for the calculation of the degree of cerebral atrophy is proposed. Using this formula and the normal range, pathological cerebral atrophy is easily detectable.

[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.

Magnetic resonance imaging in Down's syndrome

100% of brains of Down's adults over age 40 will show Alzheimer-type neuropathologic changes in the frontal and temporal lobes. In an attempt to image these lesions, magnetic resonance imaging (MRI) was performed in seven patients with Down's syndrome, ranging in age from 17 to 45 years, using a resistive unit operating at 0.15 Tesla. All scans were within normal limits except for one 45 year-old patient with severe left temporal lobe atrophy. No areas of abnormal signal were seen in the frontal or temporal lobes and the white matter lesions commonly seen in elderly demented subjects were not visualized in this group. We conclude that these white matter lesions are likely coincidental and not causally related to Alzheimer's changes. The pathologic process leading to the formation and development of Alzheimer's changes in the brains of Down's adults may not be visible on magnetic resonance images.

Neurotoxicity in long-term survivors of small cell lung cancer

Chronic central nervous system neurotoxicity was studied in 38 long-term survivors (greater than or equal to 3 years) of small cell lung cancer who were treated at the University of Texas M. D. Anderson Hospital and Tumor Institute at Houston between 1971 and 1980. All but one patient received combination chemotherapy with or without chest irradiation. Twenty-four patients received whole brain irradiation (Group I), 22 for "elective" and two for therapeutic purposes, while 14 did not (Group II). Abnormalities in computed tomographic (CT) scans of the brain were more frequently observed in Group I than in Group II (70% vs. 0%, p less than 0.01). Clinical central nervous system neurotoxicity developed in three patients in Group I, while none developed in patients in Group II (p less than 0.05). Patients who received methotrexate and procarbazine after whole brain irradiation were at a higher risk for clinical central nervous system neurotoxicity (p less than 0.05), and for development of periventricular white matter changes in CT brain scans (p less than 0.05) than were patients in Group II. Impaired methylation of the myelin sheath is proposed as a possible underlying pathogenic mechanism.

Cerebral blood flow and brain atrophy correlated by xenon contrast CT scanning

Correlations between cerebral blood flow (CBF) measured during stable xenon contrast CT scanning and standard CT indices of brain atrophy were investigated in the patients with senile dementia of Alzheimer type, multi-infarct dementia and idiopathic Parkinson's disease. Compared to age-matched normal volunteers, significant correlations were found in patients with idiopathic Parkinson's disease between cortical and subcortical gray matter blood flow and brain atrophy estimated by the ventricular body ratio, and mild to moderate brain atrophy were correlated with stepwise CBF reductions. However, in patients with senile dementia of Alzheimer type and multi-infarct dementia, brain atrophy was not associated with stepwise CBF reductions. Overall correlations between brain atrophy and reduced CBF were weak. Mild degrees of brain atrophy are not always associated with reduced CBF.

Imaging the centenarian brain. A computed tomographic study

Ten healthy and mentally alert centenarians underwent cranial computed tomography (CT) using a fourth-generation CT scanner. The subjects ranged in age from 100 to 102 years, and included six women and four men. Two of them used alcohol on a daily basis and five had systolic blood pressures of at least 160 mmHg. The CT scans demonstrated considerable variation in the degree of cerebral atrophy, which had no relation to either sex, alcohol use, or hypertension. Three of the centenarians had evidence of mild periventricular white matter lucency. Although progressive cerebral atrophy is an integral aspect of the normal aging process in the very elderly, its exact relationship to cognitive function remains unclear.

Ethics and care for the elderly

This article uses the case of presenile and senile dementia to discuss ethical concepts that have potential to guide nursing action. The concepts of 'sanctity of life' versus 'quality of life' or 'dignity' are both unsatisfactory for directing nursing intervention whenever proxy judgment is necessary. Guidelines for action must evolve from research, the search for clinical knowledge. As an underlying attitude and additional guide the author describes a Jewish ethical perspective which defines dependence and interdependence as an essential part of human existence and accepts the inevitability of living with moral uncertainty.

Mid-line epileptiform activity in adult electroencephalograms

Nine cases among 1000 adults referred to our EEG Laboratory were found to have epileptiform discharges at the C-Z area, predominantly in the awake state. These were in the form of isolated spike and wave complexes in five cases (0.5%), and Mu-like rhythms in four (0.4%). In all cases, variable degrees of dementia were found, and the CT scan of the head revealed mild to moderate cerebral atrophy and ventricular enlargement, confirmed by quantitative measurement. It is postulated that diffuse cortical and subcortical structural alteration is a factor responsible for the genesis of mid-line epileptiform activity in adult EEG's.

Cortical abnormalities in Alzheimer's disease

Regional cerebral glucose metabolism, an index of neuronal activity, was compared in 20 patients with Alzheimer's disease and 8 age-matched normal volunteers by positron emission tomography following [18F]2-fluoro-2-deoxy-D-glucose administration. Overall cortical glucose utilization in the Alzheimer's group was 10 to 49% below that of control individuals. The posterior parietal cortex and contiguous portions of posterior temporal and anterior occipital lobes were most severely affected; frontal cortex was relatively spared. This pattern of cortical involvement is consistent with the major clinical features of Alzheimer's disease. Comparison of patients with early and more advanced dementia suggested that a substantial decline in glucose metabolism occurs before cognitive impairment becomes evident; once the patient is symptomatic, however, small additional metabolic decrements are associated with a marked deterioration in intellectual function.

Computed tomography and aging: results in a normal elderly population

CT studies on 212 normal elderly individuals were analyzed for ventricular enlargement and cortical atrophy. Results show a positive correlation between ventricular enlargement and age with greater degrees of ventricular enlargement and cortical atrophy in men as compared to women. While some degree of atrophy is common in normal elderly individuals it is mild, minimal, or noexistent in 86%.

Computed tomographic and nuclear magnetic resonance correlation of canine ceroid-lipofuscinosis with aging

Canine ceroid lipofuscinosis is a degenerative neuronal disorder which has as a distinct pathologic counterpart, neuronal ceroid lipofuscinosis or Batten's disease in humans. The disease occurs in English setters and is associated with abnormal accumulation of autofluorescent lipopigments. As such, a study of this animal model may allow insight into the aging process as well. This investigation explores the computed tomographic features of canine ceroid-lipofuscinosis and correlates these findings (progressive atrophy, inherent changes in CT/NMR tissue characteristics) with clinical and pathologic features.

Tardive dyskinesia: clinical correlation with computed tomography in patients aged less than 60 years

In a prevalence study of 335 psychiatric in-patients 49 patients (14.6%) with tardive dyskinesia were found. In view of the high prevalence of spontaneous dyskinetic syndromes in elderly patients only patients under 60 years were included (n = 21; mean age: 44.9). Clinical rating was performed with the AIMS-scale. CT measurements of ventricular enlargement and cortical atrophy were obtained. Tardive dyskinesia cases did not differ significantly from healthy controls, though some patients with severe dyskinesia showed signs of brain atrophy. These findings did not provide evidence to support neuropathological reports describing neuronal cell loss and midbrain gliosis in such patients. It is concluded that such structural brain changes in tardive dyskinesia patients are not detectable with present CT technology: they may either be due to concurrent aging processes or, in the case of younger patients, can be confirmed only by more functional methods of testing.