Grant: Collaborative Health Research Projects

There is no cure and no early detection method broadly available for Alzheimer's disease (AD). Definite diagnosis is only after death. AD has a large negative impact on individual health and an enormous cost to society. Early diagnosis and improved disease tracking lead to earlier and better treatment. Amyloid beta forms deposits in the brain early in AD. We will develop a simpler method to image amyloid beta deposits in the living neural tissue at the back of the eye. Campbell's group has shown that these deposits should be large enough to be detected in images of the eye. They could then be used to diagnose and monitor the worsening stages of AD. We will explore the association between amyloid beta in the retina and the severity of AD. Amyloid beta deposits in retinas will be assessed after death. We will characterize the location, density, size and shape of retinal deposits. In a separate UBC study, the stage of AD will be measured in the clinic before death. Theirbrains are being imaged using PET and MRI scans. In addition, markers of AD in their blood and spinal fluid are measured. Characteristics of the retinal deposits will be compared with the stage of AD assessed by all the other measures. The living brains and retinas of a mouse model of AD will be imaged as they develop AD and after death. The time of appearance and characteristics of the amyloid beta deposits in the retinas and brains will be compared. Raman spectroscopy will be investigated as a noninvasive detection method of amyloid beta deposits in the retina. From these studies, we will understand the relationship between amyloid beta deposits in the retina and the severity of AD. We will then optimize the design of a novel system which will aid the diagnosis of Alzheimer disease by imaging the living retina. From the mouse model of AD, we will collect preliminary data on the performance of the system. The eye provides a clear view of neural tissue. Diagnosis of AD via this new imaging technology will be less expensive and more accessible to patients than current brain imaging methods.