This report describes our experience with CT scanning in a patient with idiopathic familial basal ganglia calcifications. The clinical symptoms were characterized by late onset of progressive mental deterioration, seizures, involuntary movements and speech disorder. An extensive deep cerebral calcification was clearly visualized with CT as was midbrain and cerebellar calcification. Our communication is the first which documents CT profile of this rare disorder.

Basal Ganglia Diseases↗

PubMedDate not supplied

MRI description of cerebral atrophy in mouse lemur primates.

We assessed cerebral atrophy in mouse lemur primates (Microcebus murinus) by estimating CSF volume in their brains from 4.7 Tesla T2-weighted magnetic resonance images. Thirty animals aged from 1 to 10.3 years were imaged, 14 of them were followed for up to 2 years. Seven of these animals were examined for neuropathology. In 12 out of 17 animals older than 3.5 years, CSF volumes were increased. A subgroup of six animals had severe atrophy of the temporal lobe. Another subgroup of five animals displayed diffuse atrophy in addition to the temporal atrophy. One animal had a dilation of the external part of the temporal horn of the lateral ventricle in addition to the temporal atrophy. The three animals with diffuse atrophy that could be studied for neuropathology had diffuse cerebral amyloid deposits detected by immunocytochemistry. The other animals did not display amyloid deposits. Relations between the different types of atrophy as well as their causes will have to be assessed in future studies.

Age Factors↗

PubMedDate not supplied

T2-weighted MRI studies of mouse lemurs: a primate model of brain aging.

Previous histological and behavioral studies of aging mouse lemurs have demonstrated changes similar to those observed in elderly humans and in patients with Alzheimer's disease. We explored 18 animals of ages 6 months to 9 years. Axial T2-weighted images of the brain were performed on a 4.7 Tesla Bruker Biospec 47/30 system. We estimated cerebral atrophy by adding measures of high signal areas characteristic of cerebrospinal fluid (interlobular and sylvian fissures, lateral and third ventricles) of four contiguous cortical slices. We observed a significant increase of cerebral atrophy with aging and one case of an apathetic 8-year-old animal presenting a considerably higher cerebral atrophy. We also observed high correlations between decreased signal intensities and age for the pallidum, the substantia nigra, and the putamen. These results suggest that aging mouse lemurs present similar magnetic resonance images of cerebral alterations to those encountered in aging humans and that high-field T2-weighted magnetic resonance images can help in the early detection, in vivo, of animals suspected of pathological aging.

Aging↗

PubMedDate not supplied

Cerebral T2-weighted signal decrease during aging in the mouse lemur primate reflects iron accumulation.

4.7 Tesla T2-weighted magnetic resonance images showed a highly significant signal decrease in the pallidum, substantia nigra, putamen, and a less significant decrease in the thalamus and the caudate of aging mouse lemurs (Microcebus murinus). We evaluated the contribution of iron deposits to the signal decrease comparing Perls' stained histological sections of six mouse lemurs brains aged 1 to 10 years to magnetic resonance images. In young animals, none of the brain structures was stained. A large number of iron deposits were visible in the pallidum and substantia nigra of aged animals and a moderate number in the middle aged ones. In the putamen, few iron deposits were visible in aged and middle-aged animals. The thalamus and the caudate appeared unstained with Perls' technique; iron was too low to be detected. The intensification of the reaction by diaminobenzidine revealed iron deposits in the thalamus of aging animals. This study suggests that in mouse lemurs, iron deposits are responsible for T2-weighted signal decrease in the central gray nuclei.

Aging↗

PubMedDate not supplied

Language impairment and rate of cognitive decline in Alzheimer's disease.

There is growing evidence that AD consists of different subtypes, and that language is a pertinent factor to identify a subgroup with a fast rate of cognitive decline. We report the first results of a longitudinal study in which we compared two groups of patients with probable AD. The main result showed that a subgroup with stable MMSE scores during a 1-year follow-up period had an impairment in language domains which are usually preserved until an advanced stage of the disease. It is proposed that this group may correspond to a variety of AD who, in addition to symptoms of AD, present characteristics of primary progressive aphasia. In other respects, we underscore that the high loading in language-mediated tasks of the MMSE makes it a poor index to accurately measure the rate of cognitive decline.

Aged↗

PubMedDate not supplied

Specificity of temporal amygdala atrophy in Alzheimer's disease: quantitative assessment with magnetic resonance imaging.

The aim of the study was to assess the specificity of temporal amygdala (TA) atrophy with magnetic resonance imaging (MRI) by comparing a group of early impaired patients with Alzheimer's disease (AD) with 'other types of dementia' and controls. In this prospective case-control study, 41 patients were selected: 12 with probable AD according to NINCDS-ADRDA and CERAD inclusion and exclusion criteria, 14 with other types of dementia and 15 age-matched control subjects. Two radiologists blindly measured the TA volumes on coronal oblique contiguous slices with a 1.5-tesla MRI scanner. TA volume measurements obtained by the 2 observers and right-left TA values were not significantly different. A significant TA atrophy was found in the AD group as compared to the other groups, with 39.7% (p < 0.001) difference in TA volumes between AD and other types of dementia groups and 41.4% (p < 0.0005) difference between AD and control groups. There was no significant difference between other types of dementia and control groups. There was an overlap between the three groups for 4 patients. TA atrophy assessed with MRI could be of diagnostic value in AD, especially in the early stage of the disease.

Aged↗