Clinical investigations of Alzheimer's disease (AD) have been limited by diagnostic inaccuracy. We employed explicit clinical inclusion and exclusion criteria to identify subjects with senile dementia of the Alzheimer type (SDAT). In a consecutive series of 26 postmortem examinations from this sample, AD was histologically verified in all subjects and was the primary dementing illness. Seventeen of the 26 SDAT subjects had been diagnosed when only mildly demented. Two control subjects were examined neuropathologically; AD was absent in both. We conclude that research clinical diagnostic criteria for SDAT, even in its mild stage, are valid.

CNS infarcts were demonstrated in 12 of 24 autopsied patients with sickle cell anemia. The infarcts occurred most extensively in the territory supplied by the distal branches of the internal carotid artery, especially the anterior-middle cerebral artery boundary zone. They were regularly associated with organizing and recanalizing thrombi involving the distal cervical and proximal intracranial divisions of the internal carotid system. On the basis of these findings, we infer that the pathogenesis of the infarction involves perfusion failure or intraarterial embolization in addition to intravascular sickling.

The significance of periventricular lucencies in the white matter on CT in demented patients is not understood. We studied the relationship of these changes to mental status of subjects with senile dementia of the Alzheimer type. A semiquantitative method showed more numerous and extensive lucencies in demented than in healthy elderly. Neuropathologic examination of five subjects with these changes and confirmed Alzheimer's disease revealed diffuse white matter pallor without infarction. There were no hypertensive vascular changes, although limited hyaline thickening was present.

Surgical specimens of malignant, supratentorial, astrocytic gliomas from 503 patients randomized on an RTOG‐ECOG treatment protocol were examined by central pathologic review. The diagnosis of glioblastoma multiforme (GBM) was made only when one or more foci of coagulation necrosis involving astrocytic tumor cells were identified histologically. Malignant astrocytic neoplasms without necrosis were classified as astrocytoma with atypical or anaplastic features (AAF). The median survival stratifying for treatment for patients with GBM was eight months compared to 28 months for patients with AAF. In most cases the specimens were received with a Kernohan grade. On the basis of these grades, patients with astrocytoma Grade 3 had a median survival of ten months as compared to a median survival of nine months for those with astrocytoma Grade 4. Observations demonstrate that necrosis is a reliable, decisive prognostic factor associated with malignant, supratentorial, astrocytic gliomas. The Kernohan system is of limited value in assessing prognosis for this group of tumors.

No abstract