Preclinical Imaging

(Foster, Bartha, PradoCechetto, StrongSeguin, Leung)

Cancer Imaging. Preclinical models are used to monitor primary tumour growth, metastases, and develop new methods for detecting and staging tumours including the use of novel contrast agents by Dr. Foster and Dr. Bartha. Tumour metabolism can be followed using magnetic resonance spectroscopy.

U87MG brain tumour observed with T1-weighted imaging (A), T2-weighted
imaging (B), and steady-state free precession imaging (C) on the 9.4 T MRI. Tumour
volume can be measured over time to monitor progression and treatment response.


Alzheimer Imaging and Spectroscopy. 
Drs. Prado and Bartha use MRI and MR spectroscopy to monitor neurodegeration and metabolite level disturbances of various models of Alzheimer disease. The effect of genetic alterations can then be studied in-vivo over time and correlated to behaviour.

Short echo-time 1H MR spectrum acquired at 9.4 Tesla. Inset shows T2-weighted coronal image with approximate location of voxel of interest outlined in red. Major metabolites of interest are labeled: N-acetylaspartate (NAA), glutamate (Glu), glutamine (Gln), creatine (Cr), choline (Cho), taurine (Tau), and myo-inositol (Myo).

  


Stroke Imaging.
Drs. Cechetto, Bartha, Prado, and Strong use MRI to follow tissue damage following stroke. For example:

  1. To study the mechanism of vascular cognitive impairment and prevention of strokes following occlusion of middle cerebral artery and intracerebral endothelin injection by monitoring the stroke size over time.
  2. To study the effect of amyloid presence on stroke volume
  3. To track spinal cord lesions caused by stroke using manganese enhanced MRI.
  4. To investigate novel mechanisms that regulate stroke lesion volume and functional recovery after stroke in different groups of genetically-modified mice.

Spinal Cord. Dr. Seguin uses MRI to visualize the spinal cord during intervertebral disc development.

Alcohol Exposure. Dr. Singh uses MRI to identify the effects of alcohol on the brain. In particular, to measure changes in brain size and metabolite levels in ethanol exposed mice.

Brain Function. MRI can be used to to reveal the functional networks in rat brain by independent component analysis of resting-state fMRI (Drs. Leung, Prado, Bartha). Pharmacological MRI can elucidate the function of specific populations of neurons following pharmacological challenge.