Sulcal Cerebrospinal Fluid Research Articles

Increase in brain cerebrospinal fluid volume is greater in older than in younger alcoholic patients: A replication study and CT/MRI comparison

This cross-sectional study used a semi-automated analysis technique to quantify regional brain cerebrospinal fluid (CSF) volumes derived from computed tomography (CT) in 84 healthy men ranging from 21 to 82 years of age and 28 patients meeting Research Diagnostic Criteria for alcohol dependence. The goals were to replicate an earlier CT study of an independent sample of alcoholic and control subjects (Pfefferbaum et al., 1988 a; Zipursky et al., 1988) and to compare CT assessments of brain changes with magnetic resonance imaging (MRI) assessments made in the same alcoholic patients (Pfefferbaum et al., 1992). Regional brain changes associated with normal aging were derived by regression analysis, using CT data collected from the healthy control subjects. As in the earlier CT study and in the concurrent MRI study, ventricular and sulcal CSF volumes in alcoholic patients were greater than would be expected for their age. Furthermore, the present CT study replicated the previous CT and MRI findings of a positive relationship between age and CSF volume enlargement in alcoholic patients over and above the normal age-related increase in CSF volume, suggesting greater vulnerability of the aging brain to alcohol. Comparison of CT-and MRI-derived estimates of ventricular and cortical sulcal volume revealed high correlations (>0.80). MRI and CT produced similar absolute ventricular volumes, while MRI produced larger sulcal volume estimates than did CT. The difference in sulcal volume estimate may be due to differences between CT and MRI in slice thickness and sensitivity to partial volume effects.

Fully automated segmentation of cerebrospinal fluid in computed tomography

A method is presented for automated delineation and measurement of cerebrospinal fluid (CSF) regions in computed tomographic (CT) sections. Regions of skull and scalp are removed by using a linear discriminant analysis approach. Beam-hardening artifact is reduced by subtracting from each section the average radial intensity profile, characterized by a polynomial function. Remaining intensity gradients are suppressed by implementing CSF segmentation with a local thresholding technique based on maximum-entropy principles. CSF fractions from 12 regions of interest (ROIs) were measured in 10 patients with alcoholic Korsakoff syndrome and 9 normal volunteers. The same ROIs were also assessed by an interactive segmentation method, which enabled the operator to compensate for beam-hardening distortions by selecting suitable threshold values for each ROI. Both methods identified the same ROIs as displaying statistically significant differences between the two subject groups. However, interactive segmentation underestimated sulcal CSF by 20–70%, which was confirmed by applying both methods to CT scans of an anthropomorphic phantom. Hence, in contrast to interactive thresholding, unsupervised segmentation relies on firmly fixed criteria that reduce the influence of beam-hardening distortions and provide more objective results.

Greater Abnormalities of Brain Cerebrospinal Fluid Volumes in Younger Than in Older Patients With Alzheimer's Disease

This study used a semiautomated analysis technique to quantify differences in regional brain cerebrospinal fluid volumes observed with computed tomography between healthy adults and patients with Alzheimer's disease (AD). Cross-sectional, between-subject design, using an age-regression model. Palo Alto (Calif) Department of Veterans Affairs Medical Center. The 117 patients with probable or definite AD were recruited from the Geriatric Psychiatry Research Unit and National Institute of Mental Health Clinical Research Center of the Palo Alto Department of Veterans Affairs Medical Center. The 114 healthy volunteers were recruited from the local community. Cerebrospinal fluid volumes estimated from computed tomographic scans and neuropsychological test scores. The computed tomographic estimates of ventricular and sulcal cerebrospinal fluid volumes increased significantly in all sampled brain regions in normal aging and were vastly larger in AD than in normal aging. Furthermore, younger patients with AD had significantly greater cerebrospinal fluid volume enlargement than did older patients with AD compared with healthy controls of their age. When the AD group was divided on the basis of reported age at symptom onset, patients in the early-onset group (onset before age 65 years) were quantitatively more abnormal than and showed a different pattern of abnormality from the patients in the late-onset group. This onset difference was also evident in neuropsychological test performance. This cross-sectional study revealed a number of converging findings that suggested greater abnormality in the early-onset than in the late-onset group of patients with AD. The possibility remains, however, that the two onset groups represent different stages along a continuum of pathologic changes.

Age-related differences in volumes of subcortical nuclei, brain matter, and cerebrospinal fluid in healthy men as measured with magnetic resonance imaging.

Magnetic resonance imaging was used to determine the volumes of brain, subcortical gray matter nuclei, and the ventricular and sulcal cerebrospinal fluid in 27 healthy men. Subjects were divided into young (less than 35 years, n = 10) and old (greater than 60 years, n = 17) groups. Volumes were normalized as percent intracranial volume. Older subjects had significantly less brain mass and significantly larger ventricular and peripheral cerebrospinal fluid volumes than the younger men. The caudate and lenticular nuclei were significantly smaller in older than younger men. This significant difference remained when their volumes were expressed as a ratio of cerebral brain matter volume. This cross-sectional study demonstrates age-related atrophy and concurrent dilation of cerebrospinal fluid spaces in healthy subjects. Of brain regions affected, the caudate and lenticular nuclei are significantly more affected by healthy aging than is cerebral brain matter; this may account for some of the motor abnormalities in aging.

Magnetic Resonance Imaging in Schizophrenia

The study reports magnetic resonance imaging data for 42 patients with schizophrenia and 43 normal controls. Volumetric measures were obtained with a validated computerized algorithm for segmentation of cranial volume into brain tissue and central and peripheral cerebrospinal fluid (CSF), with high inter-operator reliability. Patients did not differ significantly in whole-brain volume, but had higher whole-brain CSF volume and higher ratios of ventricular and sulcal CSF to cranial volume. Covarying age and education did not affect the differences. However, there was considerable overlap both in CSF volumes and in volume-cranium ratios, and most patients were within the normal range. This suggests that anatomic changes reflected in CSF can provide a limited substrate for schizophrenia and may apply only to subpopulations. Although there was no gender x diagnosis interaction, the results for sulcal CSF were significant only for men, whereas for women, the ventricular ratios were marginally higher in patients.

Brain and intracranial cavity volumes: in vivo determination by MRI.

Brain volume is altered by pathological processes such as swelling or atrophy yet until now this is a parameter which could only be determined at post mortem. This paper describes a non-invasive technique using MRI which permits the in vivo determination of brain volume (BV), intracranial cavity volume (ICV), ventricular, cortical sulcal and total intracranial CSF volumes. The technique was applied to 40 normal volunteers (20 males, 20 females) to investigate the variation of these parameters with age and sex after normalisation with respect to ICV. There was found to be a significant decrease in normalised brain volume between the ages of 20 and 60 years in males by 1.6% per decade. In females the decrease was less (0.5%) but was not statistically significant. This technique will make it possible, for the first time, to investigate prospectively the correlation between mental function and brain volume in illness and ageing.

Intracranial CSF volumes: natural variations and physiological changes measured by MRI.

Cranial CSF volumes, for the first time including CSF in the subarachnoid space, can be measured by Magnetic Resonance Imaging (MRI). The MRI sequence causes signal from the grey matter and white matter to cancel producing a contrast of 200: 1 between a unit of CSF and a unit of brain. We have assessed the variations between normal individuals and investigated some of the physiological factors that might influence cranial CSF volumes. Total CSF volumes were measured in 64 normal subjects, aged from 18-64 years (mean 38 years). Ventricular, cortical sulcal and posterior fossa volumes were also calculated separately. In 20 females with a normal menstrual cycle, CSF volumes were measured mid cycle and premenstrually; 10 post menopausal females and 10 males were rescanned after an interval of 2 weeks. Total cranial CSF volume were calculated before and during inhalation of 7% CO2 and before and during hyperventilation while breathing 60% O2, in 12 normal subjects. Total intracranial CSF volume ranged from 57.1-286.5 ml. Total intracranial and cortical sulcal CSF volumes increased more steeply with age than ventricular or posterior fossa CSF volumes. Males had more cranial CSF than females. Total CSF volume increased premenstrually in 19 females. Males and post-menopausal females did not have a significant change in CSF volume, on repeat examination. CO2 inhalation produced a mean increase of paCO2 of 17.2 mmHg and CSF volume decreased in all subjects (mean 9.4 ml). Cranial CSF volume increased in 11 subjects during O2 inhalation (range -0.5 to +26.7 ml mean 10.9 ml).(ABSTRACT TRUNCATED AT 250 WORDS)