Research Programs and Labs Masthead

Laboratory Focus

Radiographic assessment is a critical aspect of patient management for many pathologies, including multiple sclerosis (MS), Alzheimer’s disease, brain tumors, and stroke. Conventional images are sensitive to downstream indicators of altered neurobiology but often lack specificity to the underlying neuropathological causes. More advanced imaging methods provide unique and complementary functional information that is directly related to pathophysiology and could have a significant clinical impact on diagnosis, prognosis, surveillance, and assessment of treatment response.

Our research focuses on developing, validating, and translating advanced magnetic resonance (MR) image acquisition and analysis methods to noninvasively assess neurological diseases and disorders. These advanced imaging methods include methods to interrogate vascular structure and function (dynamic susceptibility contrast and dynamic contrast enhanced MRI), cellular microstructure (diffusion-weighted and diffusion tensor imaging), protein content (chemical exchange saturation transfer), and hypoxia (using both MRI methods and PET radiotracers).

Ongoing research projects in the Stokes Laboratory include the development of imaging biomarkers in Alzheimer’s disease, MS, and brain tumors. We also are interested in the neurological impact of hemodynamic insufficiencies. Previously, we developed and validated a new acquisition and analysis method for perfusion MRI to provide robust quantitative hemodynamic measures. This method has improved our understanding of tumor hemodynamics and provided insight into the tumor microenvironment (vasculature, morphology, function, etc.). Work is ongoing to characterize multi-scale perfusion metrics in patients with MS.

Finally, we are working to establish advanced multi-parametric MR imaging signatures that may be indicative of early neuropathological changes in persons with normal aging, mild cognitive impairment, or Alzheimer’s disease. Our work in Alzheimer’s disease has also involved the preclinical development of an analogous set of MRI biomarkers that has allowed us to identify structural, vascular, metabolic, and molecular neuroimaging signatures in a triple transgenic mouse model of the disease.

Ashley Stokes, PhD
Ashley Stokes

Contact Information

Ashley Stokes, PhD
Assistant Professor, Imaging Research
Barrow Neurological Institute
350 West Thomas Road
Phoenix, Arizona 85013
Ashley.Stokes@DignityHealth.org