Biomedical subjects

J Sääf

Publications and source records attributed to J Sääf.

At least 19 recordsLinked to original sources

PubMed1998

Diagnostic subgrouping of depressed patients by principal component analysis and visualized pattern recognition.

A data-analytical method is described for identifying behavioral and biological variables in psychiatric patients with predictive value in defining clinical subgroups. The procedure, based on principal component analysis (PCA) and graphical analysis, was applied in a group of 28 depressed patients. The 28 depressed patients of unipolar type were observed for up to 15 years for re-evaluation of the diagnoses at the start of the study. Platelet monoamine oxidase activity, post-dexamethasone serum cortisol and serum melatonin predicted two main clinical subgroups as well as a smaller subgroup of bipolar patients. The selection procedure revealed which of several variables were predictive of subgroups that were not possible to identify by univariate methods. The three biological variables may thus be useful in further assessment of clinical subgroups of unipolar depressed patients studied by other research groups.

Adult↗

PubMed1998

Affective disorder subtyped by psychomotor symptoms, monoamine oxidase, melatonin and cortisol: identification of patients with latent bipolar disorder.

A multivariate approach using pattern recognition method was applied on a multivariable data set from patients with affective disorders comprising biological and clinical variables. The depressed patients were rated according to 23 items of the comprehensive psychopathological rating scale (CPRS). Variables of importance were selected and clusters of patients were found by combining monoamine oxidase, melatonin and post-dexamethasone cortisol with symptoms of psychomotor retardation and agitation. Patients were distributed with high scores of agitation in the extreme of one direction and with high scores of retardation in the opposite direction. By using the combined clinical and biological variables, a diagnostic subcategory with latent bipolar disorder was identified. Two clusters of unipolar patients, one with low melatonin and low psychomotor retardation scores, and one with high melatonin and high psychomotor retardation scores, were found. Identification of a patient group with latent bipolar disorder may have potential therapeutic value since bipolar patients should be taken care of by a specialist in psychiatry, avoid tricyclic antidepressant therapy and may be candidates for lithium treatment.

Adult↗

PubMed1995

Clinical symptoms and platelet monoamine oxidase in subgroups and different states of affective disorders.

Platelet monoamine oxidase activity (MAO) and clinical symptoms were examined in 116 individuals, 32 acute depressed patients and 84 healthy controls. The enzyme activity was lower in depressed women than controls. MAO activity correlated positively with rated clinical state in depressed women but not in depressed men. Patients were reexamined after 10 years and categorized into affective psychosis (endogenous) or neurotic depression (International Statistical Classification of Diseases, Injuries and Causes of Death, 1987; ICD-9). Neurotic depressed occurred frequently in the low activity group. Endogenously depressed showed positive correlation between MAO activity and rated clinical state. The association between platelet MAO activity and clinical state is discussed.

Adult↗

PubMed1995

Classification of patients with affective disorders using platelet monoamine oxidase activity, serum melatonin and post-dexamethasone cortisol.

Platelet monoamine oxidase activity (MAO), melatonin and cortisol post-dexamethasone suppression test (DST) were examined in 28 patients with major affective disorder and in 20 controls. MAO activity was lower and cortisol post-dexamethasone was higher in depressed patients. Platelet MAO activity and cortisol in depressed and controls yielded high sensitivity (90%) and specificity (89%). The patients were re-examined after 10 years and categorized into affective psychosis or neurotic depression (ICD-9). Multidimensional analysis identified one subgroup coinciding in 92% with affective psychosis and another subgroup coinciding in 87% with neurotic depression. Combination of MAO, melatonin and post-DST cortisol may be useful in the diagnosis of subgroups of depressed patients and in choice of therapy.

Adult↗

PubMed1994

White matter hyperintensities in dementia: does it matter?

The aim of the study was to investigate whether the regional distribution of white matter hyperintensities (WMH) observed by magnetic resonance imaging differed between vascular dementia and patients with late onset Alzheimer's disease. Another aim was to investigate the relations between the occurrence and degree of WMH and clinical and laboratory data as well as measures of cognitive decline. White matter hyperintensities were assessed with a low field magnetic resonance imager on 23 subjects with probable Alzheimer's disease, 25 with possible Alzheimer's disease and 31 subjects with vascular dementia. The degree and regional distribution of the WMH (expressed as relative volumes) were calculated and compared in the three groups. The relation between cognitive impairment and the degree of the WMH was also studied. The regional distribution of the WMH differed between the groups with significantly more changes in the posterior part of the brain (p < .0001) as well as in the right hemisphere (p < .0005) in the vascular demented as compared to the patients with Alzheimer's disease. No significant correlations between cognitive impairment and the degree of the WMH were found in any of the groups. The total volume of the WMH as well as the regional distribution of these changes differed significantly between vascular dementia and Alzheimer's disease. White matter hyperintensities seem not to be related to the degree of global cognitive decline in dementia and whether it plays a causative role in the development of dementia symptoms needs to be more thoroughly investigated.

Aged↗

PubMed1993

Cognitive functions and brain structures: a quantitative study of CSF volumes on Alzheimer patients and healthy control subjects.

In the present study we have investigated the connection between cerebrospinal fluid spaces and cognitive function in patients with senile dementia of Alzheimer type (SDAT) and in successfully aged control subjects. The cerebrospinal fluid (CSF) volumes were measured using a low field MRI technique, and the cognitive functions were assessed with a number of psychometric tests. We found that the SDAT patients showed significantly larger relative volumes in all examined CSF spaces. The largest differences between the groups were found in the volumes of the temporal horns. We also found a significant correlation between the relative CSF volumes in the basal parts of the brain, and episodic memory tests. Significant correlations were also detected between the relative volumes of the lateral ventricles, and degree of dementia as well as between the relative volumes of the lateral ventricles and episodic memory tests.

Aged↗

PubMed1992

Visual rating of magnetic resonance images of human cerebrospinal fluid spaces and white brain matter: relation to sex and age in healthy volunteers.

The size of the cerebrospinal fluid spaces and the occurrence of white matter lesions were estimated from the intracranial volumes of 76 apparently healthy adult volunteers of different ages using 0.02-T/0.8-MHz magnetic resonance imaging. A relation between the occurrence of white matter lesions and the size of cerebrospinal fluid spaces independent of age could not be demonstrated. In men, white matter changes were more numerous and lateral ventricular size was larger, but sex differences were not statistically significant except for lateral ventricular size. The results confirm that age is the most significant parameter correlated with alterations in brain anatomy over time. Body mass and other clinical parameters were not influential factors in the present material.

Age Factors↗

PubMed1992

Quantitative estimation of brain white matter abnormalities in elderly subjects using magnetic resonance imaging.

Twenty-five elderly subjects were examined with brain magnetic resonance imaging (MRI). The subjects were divided into two groups: those with Mini-Mental State Examination (MMSE) scores above 25, and those subjects with MMSE scores between 18 and 24. The degree of white matter abnormalities (WMA) (expressed as relative volumes) as well as the presence of cerebrovascular risk factors were evaluated in the two groups. We found that a) subjects with low MMSE scores had significantly larger relative volumes of WMA than the subjects with higher scores, b) a significant correlation (rs = 0.53, p < 0.009) between MMSE scores and the relative volume of WMA was also established, and c) a weak significant correlation (rs = -0.51, p < 0.05) between arterial blood pressure and WMA was found in the subjects with high MMSE scores. Besides these findings no other correlations between the presence of cerebrovascular risk factors and WMA were found in any of the groups.

Aged↗

PubMed1992

Quantitative estimations of cerebrospinal fluid spaces and brain regions in healthy controls using computer-assisted tissue classification of magnetic resonance images: relation to age and sex.

Computer-assisted tissue classification based on MR intensity values in spin echo and inversion recovery images were used for area measurements of different brain structures in 76 apparently healthy volunteers of various ages. The classification was made from transaxial sections through the basal ganglia and discriminated between brain tissue and cerebrospinal fluid. The measurements based on this discrimination demonstrated larger intracranial areas in men than women. In the total group, sex differences were not observed when the measured structures were corrected for interindividual differences in cranial size. In subjects older than 60 years relative lateral ventricular area was larger and relative brain area smaller in men than women. The lateral ventricles, the Sylvian fissures and the brain area showed the most marked relation to age. The age-relation was more marked for left hemispheric structures.

Adult↗

PubMed1992

MRI in psychiatry: 731 cases.

The frequency of brain pathology found in the 731 patients who underwent MRI scans in the present study was higher than expected on the basis of reports in the literature (Owens et al., 1980). This underlines the value of a simple MRI examination as an effective diagnostic complement in the investigation of patients with psychiatric symptoms that may have an underlying organic basis.

Adult↗

PubMed1992

Chromosomal aberrations in a patient with severe psychopathology.

The case of a female patient showing aggressive, compulsive, destructive behaviour, ritualistic faecal smearing, and hyperactivity is presented. The behaviour is long standing, therapy-resistant, and its aetiology is unknown, although it is seemingly associated with chromosomal abnormalities secondary to abnormal plasma factors.

Abnormalities, Multiple↗

PubMed1991

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

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

Adult↗

PubMed1991

T1 and T2 relaxation time estimates in the normal human brain.

Magnetic resonance (MR) relaxation time constants T1 and T2 were estimated in frontal and occipital white matter, the caudate nucleus, and the thalamus nucleus in 79 healthy subjects aged 19-85 years. The in vivo estimates were obtained with 0.02-T and 0.8-MHz MR imaging. T1 values were estimated from a series of inversion-recovery images and T2 values from spin-echo images with a single-section, single-echo technique. Although estimates were obtained from only one section, the investigated regions were distinguished from each other by the T1 values. With a polynomial regression test, the T1 data fit a cradle-shaped relation to age, with minimal values at ages 40-45 years. Sex and laterality did not influence the age-dependency results, but differences in the age-dependence curves for men and women were seen. The inclusion of 10 individuals with somatic disorders did not alter the findings.

Adult↗

PubMed1990

Cerebral abnormalities in Wilson's disease as evaluated by ultra-low-field magnetic resonance imaging and computerized image processing.

The cerebral involvement of a 13-yr-old boy with Wilson's disease was serially evaluated during the first 18 mo of D-penicillamine treatment. An ultra-low-field magnetic resonance imaging (ULF MRI) system, operating at 0.02 T, with computerized image processing was used. The half-yr period prior to the clinical diagnosis was set, the patient had showed poor school performance, emotional lability, deteriorating handwriting, progressively slow, gross, and fine motor functions, and a fixed rigid smile. No overt signs of liver disease were found. With D-penicillamine treatment (1-1.5 g/d) a continuous improvement was seen. The pretreatment MRI investigation showed pronounced pathological transformation in the basal ganglia. However, changes were seen also in most other parts of the brain indicating diffuse involvement. During treatment the computerized MR images became gradually more normal. The current magnetic resonance imaging system with computerized image processing is a sensitive and simple method for evaluation of subtle parenchymal changes of the brain.

Adolescent↗

PubMed1990

Evaluation of syringomyelia and Chiari malformations using ultra-low magnetic resonance imaging.

The accuracy of ultra-low field magnetic resonance imaging (MRI) compared to medium-field MRI in detecting syringomyelia and associated Chiari malformations is examined. In all cases the size of the syrinxes and the type and extent of the Chiari malformations was clearly shown at low-field MRI. The present spatial solution and high sensitivity allows for low-field imagers to localize even minor morphological changes of the spinal cord, brainstem, and cerebellum.

Adolescent↗

PubMed1990

Quantitative detection of brain aberrations in human immunodeficiency virus type 1-infected individuals by magnetic resonance imaging.

The brains of 65 individuals with antibodies to human immunodeficiency virus type 1 (HIV-1), 20 HIV-1 seronegative homosexual men, and 75 heterosexual controls were examined by a quantitative magnetic resonance imaging technique. A white matter aberration was detected most frequently in patients with AIDS-related complex (ARC) or AIDS, but also in asymptomatic HIV-1 seropositive persons and in HIV-1 seronegative homosexual men, of whom two of three tested were reactive for HIV-1 DNA by polymerase chain reaction. The aberration was not found in the control group. Brain atrophy was mainly confined to patients with ARC or AIDS. The brain lesions correlated with the presence of HIV-1 in cerebrospinal fluid and with elevated levels of beta 2-microglobulin and neopterin. The most pronounced brain aberrations were in patients with AIDS-dementia complex. These findings indicate that brain aberrations may occur in persons in the early stages of HIV-1 infection, although to no greater extent than in HIV-1 seronegative homosexual men. The occurrence of pronounced brain lesions seems to be associated with the presence of an advanced immunodeficiency.

AIDS Dementia Complex↗

PubMed1990

Circulatory monitoring of children during anaesthesia in low-field magnetic resonance imaging.

Anaesthesia for patients in a Magnetic Resonance Imaging (MRI) scanner provides some problems for the design of both the anaesthetic and the monitoring equipment. This report presents a technique for continuously displaying the heart rate during anaesthesia for children in an MRI scanner. The monitoring system used light to detect differences in skin capillary circulation, and the light was transferred to and from the patient via fiberoptic cables. After amplification, the signal was displayed "on line" on a cardioscope, thus continuously presenting heart rate and, in part, a qualitative view of the skin vascular resistance.

Adolescent↗

PubMed1990

The brain in healthy aged individuals: MR imaging.

Twenty-four healthy aged individuals with above-average intellectual function were studied with use of a low-field-strength (0.02-T) magnetic resonance (MR) imager. The group was carefully selected so as not to include persons with signs of arteriosclerotic diseases, major somatic disease, or a history of brain disease or dementia in the family. The width of the subarachnoid spaces and lateral ventricles, as well as the frequency and degree of brain white-matter lesions, were described with the use of a visual rating scale. White matter lesions were found in less than 9% of the subjects. The lateral brain ventricles were enlarged in 8% of all individuals and the cortical cerebrospinal fluid (CSF) spaces in more than 40% of all individuals. Moreover, T1 and T2 were estimated in different brain areas, and a positive correlation between T1 in the frontal white matter and age was found. A computer-assisted classification procedure was used to estimate brain tissue and CSF areas. The results of this procedure strongly correlated with the visually estimated ventricular size.

Aged↗