Brain Imaging
The development of innovative imaging techniques is a key feature of the research program at IND. Imaging research at IND focuses on functional imaging technology using Positron Emission Tomography (PET) and Single Photon Emission Computerized Tomography (SPECT) imaging. Using specific radioactively labeled molecules as tags or markers, in conjunction with PET or SPECT imaging offers the opportunity to view the neurochemical activity of the brain. Functional imaging with PET and SPECT imaging allows us to understand activity in the brain and subtle changes that may occur in early Alzheimer’s disease, Parkinson’s disease and other neurodegenerative conditions.
The primary goals of the PET and SPECT imaging studies at IND are:
Improving the accuracy of diagnosis of neurodegenerative conditions (Alzheimer’s disease, Parkinson’s disease and other neurologic conditions)
Enable an earlier diagnosis of neurologic conditions
Evaluate severity of disease and monitor disease progression
Evaluate the effect of potential disease modifying medications
Identify the neurochemical changes occurring with neurodegeneration leading to the development of targets for new, more effective medications
Imaging in Alzheimer’s Disease
A major advancement in Alzheimer’s disease research has been the development of amyloid imaging. It is well recognized that individuals with Alzheimer’s disease have an accumulation of a protein called amyloid in the brain. Several therapies aimed at slowing the progression of Alzheimer’s disease by reducing amyloid deposition are being testing in clinical trials. Imaging to detect amyloid in the brain is available in research settings and provides information that is used in conjunction with clinical evaluations. Amyloid imaging may be useful in clarifying a diagnosis of Alzheimer’s disease and differentiating this from other forms of dementia.
An example of amyloid imaging is provided in the figure. In this figure, there is increased activity (bright red and yellow) in the patient with Alzheimer’s disease representing the presence of amyloid in the brain compared to relatively no activity in the healthy control image.
Imaging in Parkinson’s Disease
Over the past decade researchers at IND have developed and utilized dopamine transporter imaging in several studies to evaluate the diagnosis and monitor progression of Parkinson’s disease. In our studies, dopamine transporter imaging using SPECT discriminated between individuals with Parkinson’s disease and healthy subjects with a sensitivity of about 98%.
In addition to dopamine transporter imaging, several other imaging modalities evaluating neurochemical systems are under development. Neurochemical changes other than dopamine may be responsible for the non-motor symptoms of Parkinson’s disease including depression, anxiety, sleep difficulties and change in cognition. Understanding these neurochemical changes in the brain offers the opportunity to develop medications to improve both the motor and non-motor symptoms that occur in Parkinson’s disease.