Metastases to meningioma.

We describe a patient with metastatic disease to an intracranial meningioma in which MR images showed multiple foci of intense enhancement within a background of moderate enhancement. The discrete foci proved to be metastatic disease from the patient's known breast carcinoma.

Relationship between trinucleotide repeats and neuropathological changes in Huntington's disease.

The discovery of the Huntington's disease (HD) gene has provided the impetus to determine the association between the triplet repeat sequences and clinical manifestations of the disease. The present study is directed toward determining the relationship between the triplet repeat sequences and severity of the neurodegenerative process. Nineteen HD postmortem cases were evaluated for neuropathological changes as well as for the number of trinucleotide repeat sequences, each in a blinded fashion. Each case was assigned a gross grade according to the scale of Vonsattel and colleagues (1985); neuronal counts were then performed on both the caudate and the putamen. For 7 of the postmortem cases, blood had been collected prior to death and was analyzed for the HD gene. For the 12 remaining cases for which blood was unavailable, DNA from the frontal neocortex and striatum was extracted from frozen or formalin-fixed paraffinized tissue and subsequently analyzed for the HD gene. When correlation was made for age at death, greater numbers of trinucleotide repeats were associated with greater neuronal loss, in both the caudate (r = 0.9641, p < 0.001) and the putamen (r = 0.9652, p < 0.001). When correction was made for disease duration, the correlation was again significant, for both the caudate (r = 0.6396, p < 0.01) and the putamen (r = 0.6710, p < 0.001). This suggests that in HD, longer trinucleotide repeat length is associated with a faster rate of deterioration and greater pathological severity. A comparison of trinucleotide repeat length in different brain regions in 4 of the HD postmortem cases associated with greater numbers of repeats consistently demonstrated fewer repeats in the cerebellum than in the frontal cortex, striatum or blood.

Diagnosis of vascular dementia: Consortium of Canadian Centres for Clinical Cognitive Research concensus statement.

Interest in vascular causes for cognitive impairment is increasing, in recognition that such causes are common, and possibly preventable. This has led to attempts to better define vascular dementia and its natural history. Several sets of criteria for the diagnosis of vascular dementia have been proposed. We provide a brief overview of the background to the initiation of a Canadian consensus conference, established by the Consortium of Canadian Centres for Clinical Cognitive Research (C5R) and report the conclusions reached at that conference. To date, no one set of criteria is demonstrably superior to another; we have therefore not endorsed any of the competing sets, nor have we recommended our own. Instead we suggest that empiric studies are required to establish valid criteria. A diagnostic checklist, which combines existing criteria and additional data, is attached for clinicians wishing to participate in such studies.

A new look at pituitary adenomas: structure elucidating function.

Cases of seven different types of surgically resected pituitary adenoma are described. Included are tumours secreting prolactin or growth hormone or both, and nonfunctioning tumours--undifferentiated and oncocytic tumours, and one tumour with cells of the adrenocorticotropin-melanocyte-stimulating hormone type. The final interpretation of a case of pituitary adenoma should include an assessment of thorough morphologic studies, using not only routine staining and light microscopy but also immunostaining and electron microscopy, to complement the biochemical, radiologic and clinical evaluation.