Alexander Rauscher: Associate Professor at Department of Pediatrics, UBC Faculty of Medicine

Associate Professor

Faculty of Medicine

Research Classification

Physical sciences

Neurosciences, medical and physiological and health aspects

Research Interests

magnetic resonance imaging

physics

quantitative susceptibility mapping

myelin water imaging

brain

maschine learning

Relevant Degree Programs

View all programs

Affiliations to Research Centres, Institutes & Clusters

BC Children's Hospital Research Institute

Biomedical Imaging and Artificial Intelligence

Centre for Brain Health

Research Options

I am available and interested in collaborations (e.g. clusters, grants).

I am interested in and conduct interdisciplinary research.

I am interested in working with undergraduate students on research projects.

Open All

Research Methodology

Magnetic Resonance Imaging

numerical simulations

machine learning

Recruitment

Looking to recruit:

Master's students

Doctoral students

Postdoctoral Fellows

Desired start dates: Any time / year round

Potential research project areas:

MRI of multiple sclerosis, modelling of the MRI signal, quantitative susceptibility mapping, myelin water imaging, MRI physics, deep learning

Ideal Applicant Profile:

Background in physics, electrical engineering, computer science or equivalent.
Please note that, while my main affiliation is the department of Pediatrics, I mainly supervise students in the department of Physics and Astronomy. I am also affiliated with the Physics department and the Radiology department.

Interest in biological systems

Programming skills depending on level (undergrad to PhD)

We are actively working on maintaining a high level of diversity at our lab. Members of traditionally disadvantaged groups (based on socioeconomic background, ethnicity, sex/gender, facing any hardships in life, etc) are particularly encouraged to apply.

Other options:

I support public scholarship, e.g. through the Public Scholars Initiative, and am available to supervise students and Postdocs interested in collaborating with external partners as part of their research.

I support experiential learning experiences, such as internships and work placements, for my graduate students and Postdocs.

I am open to hosting Visiting International Research Students (non-degree, up to 12 months).

I am interested in hiring Co-op students for research placements.

Complete these steps before you reach out to a faculty member!

Check requirements

Familiarize yourself with program requirements. You want to learn as much as possible from the information available to you before you reach out to a faculty member. Be sure to visit the graduate degree program listing and program-specific websites.
Check whether the program requires you to seek commitment from a supervisor prior to submitting an application. For some programs this is an essential step while others match successful applicants with faculty members within the first year of study. This is either indicated in the program profile under "Admission Information & Requirements" - "Prepare Application" - "Supervision" or on the program website.

Focus your search

Identify specific faculty members who are conducting research in your specific area of interest.
Establish that your research interests align with the faculty member’s research interests.
- Read up on the faculty members in the program and the research being conducted in the department.
- Familiarize yourself with their work, read their recent publications and past theses/dissertations that they supervised. Be certain that their research is indeed what you are hoping to study.

Make a good impression

Compose an error-free and grammatically correct email addressed to your specifically targeted faculty member, and remember to use their correct titles.
- Do not send non-specific, mass emails to everyone in the department hoping for a match.
- Address the faculty members by name. Your contact should be genuine rather than generic.
Include a brief outline of your academic background, why you are interested in working with the faculty member, and what experience you could bring to the department. The supervision enquiry form guides you with targeted questions. Ensure to craft compelling answers to these questions.
Highlight your achievements and why you are a top student. Faculty members receive dozens of requests from prospective students and you may have less than 30 seconds to pique someone’s interest.
Demonstrate that you are familiar with their research:
- Convey the specific ways you are a good fit for the program.
- Convey the specific ways the program/lab/faculty member is a good fit for the research you are interested in/already conducting.
Be enthusiastic, but don’t overdo it.

Attend an information session

G+PS regularly provides virtual sessions that focus on admission requirements and procedures and tips how to improve your application.

Supervision Enquiry

If you have reviewed some of this faculty member's publications, understand their research interests and have reviewed the admission requirements, you may .

Graduate Student Supervision

Doctoral Student Supervision (Jan 2008 - Nov 2020)

Gradient and spin echo magnetic resonance imaging for the characterization of myelin health in multiple sclerosis (2020)

Multiple sclerosis (MS) is a complex, autoimmune disease that results in demyelination and neurodegeneration. Magnetic resonance imaging (MRI) is an essential cornerstone of MS diagnosis and clinical decision making, however, clinical MRIs lack specificity to the pathological mechanisms influencing myelin health.In this thesis, two quantitative MRI techniques were probed for their potential to study myelin health in MS. First, multi-echo spin-echo myelin water imaging (MWI) was tested for its specificity to myelin lipids, proteins and iron. We demonstrated to-date unknown sensitivity of MWI and identified MS lesion changes indicative of late-stage remyelination. Thereafter, the accuracy of MWI and its potential application at ultra-high magnetic fields were investigated. Using signal simulations, the dependence of the non-negative least-squares analysis on processing and tissue parameters was described. Myelin underestimations due to B⁺₁-inhomogeneities and noise were shown to be minimized by adjusting the T₂ range according to the echo time. To translate MWI to 7T, T₂ tissue properties in seven healthy subjects were studied in comparison to 3T. We demonstrated the feasibility of 7T-MWI and discussed current limitations in assessing short T₂ times.Secondly, susceptibility-sensitive MRI was explored, which provides greater sensitivity, albeit possibly lower specificity to myelin, than MWI. Using the phase component, we showed that the MS lesion contrast is typically not driven by iron accumulation. In simulations and with post-mortem data, it was demonstrated that iron and myelin loss in combination determine the lesions’ appearance. Thereafter, the potential of the technique to become a marker of tissue damage and repair was evaluated by studying the evolution and pathological underpinnings of acute MS lesions in eleven patients over five years. Current models and their shortcomings were discussed.Finally, two technical developments were introduced. First, a multi-dynamic, high-spatial resolution susceptibility-sensitive imaging approach was presented for visualizing the central vein sign. Using phantom and in vivo data, qualitative and quantitative agreement of the proposed approach with other imaging strategies was demonstrated. Secondly, FLAIR² was introduced, a novel contrast that improves contrast-to-noise, while shortening scan time. The potential of FLAIR² to aid automated lesion segmentation was demonstrated on real-world multi-centre clinical data.

View record

Master's Student Supervision (2010 - 2018)

Frequency shift mapping in spinal cord models of white matter demyelination (2016)

The behavior of MR phase and frequency in demyelination and damage in central nervous tissue white matter arises not only from traditionally associated bulk susceptibility changes, but also from changes to its tissue microstructure. A recently proposed generalized Lorentzian model of microstructure-related magnetic susceptibility effects predicts an increase in MR frequency due to damage in myelin in MS lesions. The same model also predicts reduction in MR frequency due to axonal degeneration. Here, we investigate the effect of both myelin and axonal damage through transection of white matter fibers in the dorsal column of rat cervical spinal cord. This injury generates secondary damage consisting of neurodegeneration along nerve tracts bilateral to the transection site, producing cases of Wallerian and retrograde degeneration free of excessive hemorrhage and inflammation. High-resolution frequency maps of degenerating tracts were correlated with histopathology for axons, myelin, degenerated myelin, and macrophages. Damage to myelin sheaths is prominent in Wallerian degeneration, where we observe strong correlations with increasing frequency up to 8 weeks post-injury. Retrograde degeneration, which consists predominantly of axonal damage, produces decreased frequency shift over time. The MR frequency shifts are sensitive to the effects of macrophage in filtration and debris clearance, which vary with white matter fiber density and affect rates of degeneration. We demonstrate how MR frequency can successfully characterize injury in rat spinal cord white matter in a manner consistent with predictions outlined by the Generalized Lorentzian Approximation Model, and conclude that these results suggest potential applications of MR frequency to supplement or replace current clinical techniques, such as myelin water and diffusion weighted imaging, as a non-invasive and quantitative method of assessing white matter damage in CNS.

View record