ABSTRACT
It is generally considered that the diagnosis of Alzheimer’s Disease (AD) can only be made with clinical evidence of dementia during life and the histological demonstration of the pathological changes in brain tissue obtained either at autopsy or diagnostic craniotomy. This chapter discusses biochemical studies are usually made on samples and the selection of subjects for such studies is influenced by many, unspecified factors. Although the biochemical examination of brain tissue obtained at cerebral biopsy does not in itself provide a diagnostic technique for dementia, this is not the case for the histological examination of such tissue which is an established technique for the investigation of neurodegenerative conditions. Factors which are likely to influence the selection of patients for post-mortem examination or cerebral biopsy will be considered. While AD is a progressive disease, this is rarely acknowledged in the interpretation of post-mortem biochemical studies. Cerebral biopsy is a diagnostic procedure and is therefore performed soon after the onset of symptoms.
