April 3, 2007, Hertfordshire, England--Pathologists from around the world are being offered their first opportunity to view in microscopic detail the original research material upon which the discovery of Alzheimer's disease was based, thanks to a Web site hosted by Carl Zeiss.
In 1906, Alois Alzheimer prepared more than 250 slides of human brain tissue from a female patient he had observed closely; he published his findings in 1907. That same year he began to treat a male patient and prepared more than 150 additional slides upon the man's death in 1910. Both lots of material were rediscovered in basements of the University of Munich after a search organized by Manuel Graeber of Imperial College London. Well-preserved and of very high technical quality, all the specimens are being scanned and saved as "virtual slides" using a Zeiss Mirax system. The virtual slides are being released progressively to be viewed over the Internet (www.zeiss.de/alzheimer).
Apart from their unique scientific value, the importance of the rediscovery of the slides is that they put an end to lingering doubts about whether Alzheimer's first patient, a 51-year-old woman, suffered from a rare metabolic disorder called metachromatic leukodystrophy rather than the disease named after him. Graeber says the rediscovered slides show no evidence of this, but the cortex does exhibit the two classic pathological signs of Alzheimer's--amyloid plaques and neurofibrillary tangles. Now, pathologists will be able to judge for themselves.
The Mirax digital-slide system produces a "virtual slide" for each specimen in just two minutes, providing the same field of view as normal microscope eyepieces without the ergonomic penalty from long periods of use. Associated software displays the virtual slides either individually or in groups, enabling rapid synchronized scanning, screening, and evaluation of multiple specimens or serial sections. Entire slides can be displayed at low magnification for easy navigation while areas examined at high magnification may be identified with colored overlays. The digital format allows easy teleconsultation via the sharing and manipulation of images across the Internet.