Department of Physics and Astronomy

The Annual ELIZABETH LAIRD Memorial Lecture

Dr. Melanie Campbell

Department of Physics and Astronomy
University of Waterloo

The eye as a window on the brain: Enabling early detection of disease processes

ABSTRACT:

We have shown that amyloid deposits occur in the retina as a marker of Alzheimer’s disease and of earlier changes prior to disease diagnosis. This is not surprising as the retina develops as an extension of the brain. We can use polarized light in a new method to make these deposits visible without a dye. This would be a much less expensive method than brain scans to identify those at risk of the disease. In turn, this means that interventions to prevent the disease could be tested at lower cost and ultimately used before damage to nerve cells in the brain is evident.

Low levels of brain amyloid are known to be deposited years before the first symptoms of the disease. We have shown that amyloid deposits occur in the retina in almost all those diagnosed with Alzheimer’s disease and also in retinas of some of those with no diagnosis. Here, I will discuss our results that show that these deposits in retinas donated after death predict severity of brain amyloid and brain changes due to Alzheimer’s disease at the time of death, including low levels of brain amyloid. 

Most amyloid deposits that we have found in the retina are large enough that we could see them in the living eye. We have imaged the deposits in retinas of the canine which develops cognitive impairment at an older age, much like Alzheimer’s disease. The counts and areas of retinal amyloid deposits predict both the cumulative score of Alzheimer’s brain pathology and the brain distribution of amyloid deposits. Thus our patented, non-invasive, polarization imaging in the eye of these deposits is a promising window onto Alzheimer’s brain pathology, including at its earliest stages. In turn, our technology will assist with earlier diagnosis and treatment, which is needed prior to the development of the first symptoms of the disease. Commercialization of this technology is being undertaken by LumeNeuro, a University of Waterloo start-up. 

The Annual Laird Lecture:

This public lecture honours a remarkable person in Western’s history and was the first lecture series in the Faculty of Science to carry the name of an individual. Prof. Laird was a pioneering physicist from Owen Sound who trained a generation of women physicists at Mount Holyoke College and subsequently left retirement during World War II to develop radar with Western’s Department of Physics.

A Reception will follow the lecture.