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H C Weinstein

Publications and source records attributed to H C Weinstein.

At least 37 records · Page 2Linked to original sources
PubMed1994

[Contribution of morphological imaging in the diagnosis of dementia. I--Alzheimer disease].

In patients with Alzheimer's disease, morphological neuroimaging techniques usually reveal signs of global cerebral atrophy which gradually worsen over time and depends on age and severity of the cognitive decline. Because of the lack of artifacts and of a more appropriate angle, magnetic resonance imaging scans may visualize a prominent atrophy of the medial temporal lobes, including hippocampal structures. Hippocampal atrophy is relatively specific of Alzheimer's disease before 65 and is related to the severity of memory disorders. White matter changes in patients without cerebrovascular risk factors are not more severe in patients with presenile Alzheimer's disease than in age-matched controls. They are, however, more severe in patients with senile onset than in age-matched controls. These findings suggest that white matter changes in patients with senile onset are consistent with a diagnosis of Alzheimer's disease.

Alzheimer Disease↗
PubMed1993

Spectral analysis of the EEG and 99m-Tc-HMPAO SPECT-scan in Alzheimer's disease.

99m-technetium-hexamethylpropylene-amineoxine (99m-Tc-HMPAO) single-photon-emission-computer-tomography (SPECT)-scans and spectral analyzed electroencephalogram (EEGs) of 20 patients with Alzheimer's disease (AD) were studied. A significant correlation was found between the temporoparietal-cerebellar-ratio (TP/C-ratio) of the SPECT-scan and the peak frequencies of leads T3-T5, C3-P3, and C4-P4 of the EEG. In addition a significant negative correlation between the TP/C-ratio and the theta/alpha-ratio (t/a-ratio) of leads T3-T5, T4-T6, C3-P3, and C4-P4 was demonstrated. Our study demonstrates that slowing of the EEG parallels a decrease in blood flow in the temporoparietal regions in AD-patients. Both findings could be parallel phenomena of regional hypometabolism.

Adult↗
PubMed1992

Memory complaints, memory disorders and focus localization in patients with partial epilepsy.

Our study aimed at analysing effects of epileptic foci on memory function in patients with partial epilepsy. Twenty-eight patients with spontaneous memory complaints and psychometrically established memory disorders were assessed by 21-channel electroencephalography recorded both during cognitive testing and during 99mTc-HMPAO single photon emission computed tomography (SPECT). Computed tomography (CT) was performed on the same day. None of the epilepsy-related factors (seizure type, seizure frequency, type of epilepsy, age at onset of the seizures, type of antiepileptic treatment) could be related directly to severity or type of memory impairment (classified into the categories 'global', 'verbal' and 'non-verbal'). Remarkably, this study found no significant relationship between EEG focus localization and severity of measured memory impairment. Most areas with hypoperfusion on the SPECT were found in the group with global (severe) amnesia, typically with a right frontal localization. Abnormalities on CT were predominantly found in the same group, however, with a right-sided parietal localization. An unanticipated finding was that the majority of temporal CT and SPECT lesions were found in the group with relatively better memory performance.

Adult↗
PubMed1992

Focus localization in patients with partial epilepsy with 99Tcm-HMPAO SPECT under continuous surface EEG monitoring.

Our study was aimed at determining the validity of 99Tcm-HMPAO single photon emission computed tomography (SPECT) in the localization of the epileptogenic focus by correlating this diagnostic method with other auxiliary investigations such as surface EEG and X-ray transmission computed tomography (CT). Twenty-eight patients with partial epilepsy and spontaneous memory complaints were assessed with a 21-channel EEG recorded during psychometric evaluation of the memory complaints and with a 12-channel EEG during 99Tcm-HMPAO SPECT. No significant agreement was observed for total focus localization by the two EEGs, CT or SPECT. The EEGs were highly reproducible. Frontal and temporal pathology on CT resulted in frontal and temporal cold spots on SPECT on the same side in six patients. In addition, SPECT demonstrated frontal, temporal or posterior temporal-inferior parietal cold spots in nine patients without accompanying pathology on CT. It is concluded that CT and SPECT may provide complementary anatomical and functional information, respectively, to the EEG. Furthermore, SPECT may be complementary to CT in visualizing functional deficits without an anatomical correlate. The value of SPECT studies in partial epilepsy may be improved by increasing the resolution of the SPECT system and by simultaneous EEG monitoring.

Adult↗
PubMed1992

Atrophy of medial temporal lobes on MRI in "probable" Alzheimer's disease and normal ageing: diagnostic value and neuropsychological correlates.

Magnetic resonance imaging (MRI) has shown a great reduction in medial temporal lobe and hippocampal volume of patients with Alzheimer's disease as compared to controls. Quantitative volumetric measurements are not yet available for routine clinical use. We investigated whether visual assessment of medial temporal lobe atrophy (MTA) on plain MRI films could distinguish patients with Alzheimer's disease (n = 21) from age matched controls (n = 21). The degree of MTA was ascertained with a ranking procedure and validated by linear measurements of the medial temporal lobe including the hippocampal formation and surrounding spaces occupied by cerebrospinal fluid. Patients with Alzheimer's disease showed a significantly higher degree of subjectively assessed MTA than controls (p = 0.0005). Linear measurements correlated highly with subjective assessment of MTA and also showed significant differences between groups. Ventricular indices did not differ significantly between groups. In Alzheimer's disease patients the degree of MTA correlated significantly with scores on the mini-mental state examination and memory tests, but poorly with mental speed tests. This study shows that MTA may be assessed quickly and easily with plain MRI films. MTA shown on MRI strongly supports the clinical diagnosis of Alzheimer's disease, is related to memory function, and seems to occur earlier in the disease process than does generalised brain atrophy.

Aged↗
PubMed1991

Tetrahydroaminoacridine and lecithin in the treatment of Alzheimer's disease. Effect on cognition, functioning in daily life, behavioural disturbances and burden experienced by the carers.

In 12 ambulant patients with a clinical diagnosis of probable Alzheimer's disease, a 12-week, double-blind, placebo-controlled study with 100 mg/day tetrahydroaminoacridine (THA) and 10 g/day lecithin is reported. The aim of the study was to find whether treatment would result in an improvement of cognition, of functioning in daily life, decrease of behavioural disturbances, and decrease in burden experienced by the carers. Two of the six THA-treated patients demonstrated an increase on cognitive test scores with a moderate increase in the other outcome measurements. There was, however, no difference between the two groups in any outcome measurement after treatment. In addition, we found a reversible rise of liver transaminases in 4 of 6 patients in the treated group. This pilot study is too small to draw definite conclusions on the use of THA alone or in combination with lecithin. Our results suggest, however, that semi-structured interviews with the carers may be of value in the evaluation of treatment effects in patients with Alzheimer's disease.

Aged↗
PubMed1991

SPECT in the diagnosis of Alzheimer's disease and multi-infarct-dementia.

SPECT with Tc-99m HM-PAO as a radiopharmaceutical was performed in 17 patients meeting research criteria for Alzheimer's disease (AD), in 10 patients with a clinical diagnosis of multi-infarct-dementia (MID) and in 12 healthy volunteers. Regional tracer uptake was measured in frontal, parietal, and temporoparietal regions. A statistically significant decrease of tracer uptake in the temporoparietal region was found in AD-patients compared with controls. AD-patients showed less activity in this region than MID-patients, but this difference did not reach statistical significance. In both AD- and MID-patients decrease of tracer uptake was not correlated with dementia severity. We conclude that SPECT brain imaging is not yet ready for routine use in the distinction between AD and MID.

Aged↗
PubMed1991

SPECT in early- and late-onset Alzheimer's disease.

We assessed with SPECT the influence of age of onset in Alzheimer's disease in patients who were matched for severity of disease with early and late onset of the disease. Twenty-six patients, severity-matched according to scores on Mini-Mental State Examination, were compared to nine controls. Comparison of the temporoparietal cerebellar ratio (TPC) revealed a statistically significantly lower ratio in the early-onset group compared to the late-onset group of patients. These results are in agreement with other imaging, structural, and neurochemical studies, supporting the view of heterogeneity of Alzheimer's disease according to age of onset.

Aged↗
PubMed1991

[CAMDEX-N: the Dutch version of the Cambridge Examination for Mental Disorders of the Elderly with automatic data processing].

In the study of dementia four distinct categories of instruments can be distinguished: instruments to examine cognitive dysfunction, to measure the severity of dementia, to assess disturbances in daily behaviour, and instruments to make a differential diagnosis of dementia. The Cambridge Examination for Mental Disorders of the Elderly (CAMDEX), published in 1988, incorporates these four categories in a single comprehensive interview schedule. Items related to the diagnosis of clouded/delirious state, depression and other psychiatric symptoms are also included. The Dutch version (CAMDEX-N) and accompanying software for data analysis and for scientific research were developed. Items were added to the section on physical and neurological examination, and to the section on ancillary investigations. The software can be adapted to future developments in dementia research.

Aged↗
PubMed1989

Determination of cerebral blood flow by SPECT: a valuable tool in the investigation of dementia?

Positron emission tomography (PET) studies have demonstrated distinctive abnormalities in Alzheimer's disease (AD), multi-infarct-dementia (MID) and Pick's disease. Since PET is a complicated and expensive technique, its clinical application will be limited in the near future. An important finding in these PET studies is persistent coupling of brain metabolism and regional cerebral blood flow (rCBF). Therefore it should be possible to demonstrate bilateral temporoparietal hypometabolism as seen in patients with clinically diagnosed AD indirectly by measuring cerebral blood flow by Single Photon Emission Computer Tomography (SPECT). We report our first experiences with SPECT in the differential diagnosis of dementia with four case histories. We demonstrated temporoparietal hypoperfusion in AD and frontal hypoperfusion in Pick's disease as shown previously by PET. We could not demonstrate a typical SPECT in MID. The main purpose of SPECT in MID could be exclusion of coexisting AD. Based on current knowledge the possibilities and the limitation of this new technique are discussed. It is concluded that rCBF-SPECT may be of value in the diagnosis of AD and Pick's disease. Before this method can be used in daily clinical routine, its diagnostic value should be established according to principles of clinical decision making.

Aged↗