Computed tomographic evidence for generalized sulcal and ventricular enlargement in schizophrenia.

Quantification of ventricular and sulcal volumes from the computed tomographic (CT) scans of 45 schizophrenic patients and 57 normal controls was carried out using a semi-automated computerized approach. The sizes of all cerebrospinal fluid spaces measured were significantly related to age in the control population. An age regression model was used to compare patients and controls. Schizophrenics had slightly larger ventricles and considerably larger sulci than controls. Enlargement of the ventricles and sulci was not correlated with measures of negative symptoms or neuropsychological impairment. The CT scans of eight very ill chronically institutionalized schizophrenics were also analyzed. Their CT findings did not differ significantly from the larger group of schizophrenics studied. Our results show that the cerebral atrophy found in schizophrenia is diffuse in nature and does not relate clearly to measures of disease severity or chronicity.

Computer-interactive method for quantifying cerebrospinal fluid and tissue in brain CT scans: effects of aging.

Presented here is a modification of a previously developed, computed, semiautomated system for quantifying the amount of CSF and tissue on brain CT scans. The technique automatically strips skull from brain and applies a two-dimensional high-pass filter to reduce spectral-shift artifact. The resultant images are presented along with the raw images, section by section, on a screen for fluid-tissue differentiation by a human scorer. This is accomplished by adjusting a one-bit display of the filtered image until a satisfactory separation threshold is found. Data can be summed within or across sections to provide measures of CSF volume in specific regions of interest such as the ventricles and sulci. A major advantage is the improved accuracy of sulcal measurement. This method has been applied to scans of 57 community volunteers, 20-84 years old. High correlations have been established between rankings performed by an experienced clinician and automated rankings (r = 0.88 with rankings based on ventricular size, and r = 0.83 with rankings based on sulcal size). Furthermore, significant correlations were found between computed measures of ventricular size and age and between sulcal widening and age.

Neurologic dysfunction in patients treated for small cell carcinoma of the lung: a clinical and radiological study.

The neurologic dysfunction in 7 patients treated for small cell carcinoma (SCC) of the lung by combination chemotherapy and prophylactic brain irradiation was evaluated. The disease appeared to be a diffuse encephalopathy frequently affecting the higher cortical functions. Five out of seven patients had progressive dysfunction leading to death in 1 to 26 months; one patient had stabilization of symptoms followed by death in 21 months, probably from the neurologic disease as well as SCC; one patient's symptoms improved. The clinical course of the neurologic disorder seemed different from the known reactions to brain irradiation and from the other neurologic syndromes associated with lung cancer. The relative contributions of cranial irradiation and treatment with chemotherapeutic agents in producing the neurotoxicity are not known. Computed tomographic (CT) brain scans done after the onset of symptoms did not show any focal signs or necrosis. However, there was a suggestion of progressive increase in intracranial fluid volume on the scans. The incidence of the disorder, 10.2% among a group of 49 patients, suggests the need for prospective studies to evaluate the problem.

The ventricular-brain ratio on computed tomography scans: validity and proper use.

The planimetric measurement of the area of the ventricles on a computed tomographic section is a convenient and useful method of assessing ventricular size when more sophisticated techniques are not available. It is commonly reported as a planimetric ventricular-brain ratio or VBR. Ventricular size is related to cranial size in normal adults which provides a rationale for the use of a ratio of areas. The ratio might not be an appropriate measure to use when studying conditions acquired in childhood. Guidelines are suggested for the use of planimetric methods to prevent bias in the experimental results.

CT measures of cerebrospinal fluid volume in alcoholics and normal volunteers.

Cranial computed tomography (CT) scans were obtained in 46 male chronic alcoholics and 31 normal male volunteers. Automated methods were used to estimate the cerebrospinal fluid (CSF) volume in various intracranial zones. Measures of the ventricular fluid volume, the volume of fluid in cortical areas on CT sections at the level of the ventricles, and the sulcal fluid volumes on two convexity sections were computed. The alcoholic group, excluding subjects with chronic liver disease, had significantly more fluid than the control group on all sulcal measures. The group difference on the ventricular measure fell short of significance. Within the alcoholic group, no significant correlation was found between the number of years of alcoholism and any fluid measure when normal age effects were taken into account. A striking degree of variability in the sulcal volumes was observed within the alcoholic group, with many subjects showing normal values while a large group showed markedly elevated values. Further studies will be necessary to determine the significance of these variations.

Computed tomography in schizophrenics and normal volunteers. I. Fluid volume.

Recent findings of enlarged ventricles and sulcal widening in the computed tomographic (CT) scans of schizophrenic subjects have raised questions about the etiology and treatment of this disorder. Measures obtained from computerized analyses of CT scans of 30 schizophrenic and 33 normal subjects showed no significant difference between the groups in ventricular or sulcal fluid volumes. The discrepancy between our findings and those of other investigators may have been due to different measurement techniques or to differences in the samples. A second study was undertaken to examine the first possibility. Its results suggest that our findings and those based on measurements of planimetric ventricle-brain ratios (VBRs) are highly correlated, but that VBRs from one study may not be compared with those in another to establish population differences. Differences in patient samples appear to constitute an important source of discrepancy in CT findings.

Computed tomography in schizophrenics and normal volunteers. II. Cranial asymmetry.

We studied cranial asymmetry in 31 schizophrenics and 32 normal volunteers, all of whom were male and right-handed. Automated measures of computed tomographic (CT) scans were used to estimate global hemicranial and hemispheric ventricular volume differences. A manual method was used to measure hemicranial asymmetries between the widths of the frontal and occipital areas on CT images. The observers making the measurements were unaware of the group membership of the subjects. High reliability was established for the manual method. In contrast to findings by other investigators, no group differences were observed. Methodologic flaws in earlier studies may account for this discrepancy.

White matter changes in cerebral computed tomography related to aging.

Changes on computed cranial tomography related to aging were studied in 123 normal subjects aged 23 to 88 years. The attenuation value of the white matter in the centrum semiovale decreased with age. When the effect of age was excluded, ventricular and sulcal size did not have an independent effect on the attenuation value. This finding suggests that there may be gradual changes in the chemical composition of white matter with aging.

Changes on computed cranial tomography with aging: intracranial fluid volume.

A semiautomated computer analysis was developed to estimate fluid volumes in each hemicranium from computed tomography scans. The method was used to estimate total ventricular and sulcal fluid in 123 normal subjects aged 23-88 years. A wide range of normal values was found. The trend was for the estimated ventricular and sulcal fluid volumes to remain relatively constant until age 60 and then to increase at an increasing rate thereafter. Ventricular enlargement occurred in the absence of sulcal enlargement and vice versa. The estimate of the volume of the ventricles was related to skull size. When this was taken into account, the size of the ventricles showed no sex difference. The cranial cavity was larger in men than in women, and, in both genders, the left hemicranium and the left ventricle were larger on the average than their right counterparts. The limitations of computed cranial tomography as a quantitative tool are discussed in detail.

Cerebral ventricular size and neuropsychological impairment in young chronic schizophrenics. Measurement by the standardized Luria-Nebraska Neuropsychological Battery.

The relationship between size of cerebral ventricles in chronic schizophrenics and performance on a comprehensive neuropsychological battery, the Standardized Luria-Nebraska Neuropsychological Battery, was investigated. Ventricular size was determined by using a planimeter to measure the size of the lateral ventricles and the ventricular body, if present, on the computerized tomographic (CT) scan image that showed the largest lateral ventricles. This number was divided by the size of the brain as a whole on the same image of the CT scan to yield a ventricular brain ratio. This ratio was then correlated with the scores on the Luria-Nebraska Neuropsychological Battery. Eight of the 14 scales of the Luria-Nebraska Neuropsychological Battery correlated significantly at the .05 level with the ventricular brain ratio in a sample of 42 chronic schizophrenics with an average age of 32.3 years. Overall, there was a multiple correlation of .72 between the ventricular brain ratio and Luria scores. The overall ventricular brain ratio for the schizophrenics was significantly above that found in normal populations. Changes in the size of the ventricles in schizophrenics appear to have significant correlates with measures of neuropsychological performance.

Differentiation of chronic schizophrenics with and without ventricular enlargement by the Luria-Nebraska Neuropsychological Battery.

The present study investigated whether the Luria-Nebraska Neuropsychological Battery could be used clinically to differentiate schizophrenics with ventricular or sulcal enlargement from schizophrenics with no such enlargement as identified by a CT scan. The study investigated 42 patients, 24 males and 18 females, who were admitted to the Nebraska Psychiatric Institute with a diagnosis of schizophrenia. The age range of the sample was from 20 to 39 years with all patients rating the definition of chronic schizophrenia according to DSM-111. Patients were tested in the present study while on antipsychotic medications. All patients were administered both the CT scan, which was analyzed using the methods of Weinberger and his associates (1979) and the Luria-Nebraska Neuropsychological Battery. Using normative data previously published in the literature, each CT scan was classified as normal or abnormal. Using objective rules of interpretation given in the paper, the Battery was 81% accurate in determining the presence of ventricular enlargement. The Battery was also 90% accurate in identifying the presence or absence of sulcal enlargement. The implications of the present results for the use of psychological testing as a possible screening device for CT scans in a psychiatric population is discussed. Also, the limitations of the methods used in this paper are discussed as well as their advantages.