Stroke imaging - computation - clinical trials
We read the flow the scanner never meant to show.
moRAVIS Lab turns routine CT angiography into quantitative haemodynamics. We measure stasis in the carotid bifurcation, model the flow that produced it, and test whether it explains who goes on to have a stroke.
Contrast stasis mapped across a carotid bifurcation from a single routine CTA acquisition.
The central question
Why do two identical-looking carotids behave so differently?
Degree of stenosis has carried the clinical decision for forty years, and it keeps disappointing us. Two patients present with the same percentage narrowing; one has a devastating stroke and the other never does. Our working answer is that the number describes the lumen, not the flow through it. Stasis, recirculation and low shear are the things that actually stage a thrombus, and they leave a signature in imaging we already acquire on every patient. The lab exists to extract that signature and test it prospectively.
“Routine CTA already contains a haemodynamic measurement. It is simply thrown away at reconstruction.”
Ravinder-Jeet Singh, Principal Investigator
What we work on
Method streams
- 01
Image Analytics
CT image post-processing
Recovering quantitative haemodynamic information from CT acquisitions that were never designed to carry it.
- 02
Computer Vision on Imaging
Segmentation, registration, and phenotyping at scale
Making the measurement reproducible enough that it can be run on thousands of scans without a human in the loop.
- 03
Mathematical Simulation
CFD and physical phantoms
Establishing that what we measure in the image is the physics we believe it is.
- 04
Clinical Trials & Imaging Database
Prospective validation
A prospectively built, outcome-linked imaging database, and the trials that run on top of it.
Flagship project
Quantifying stasis in the carotid bifurcation from routine CTA
The flagship project. A reconstruction method that turns a standard single-phase CTA into a map of contrast dwell time, and a prospective test of whether that map predicts stroke.
Latest
From the lab
Why percent stenosis keeps failing us
Forty years of carotid decision-making rest on a single number measured off a still image. Here is the case for replacing it.
Read[PLACEHOLDER] Sudbury researchers look for stroke risk hiding in routine scans
Local coverage of the lab's work on extracting haemodynamic information from CT angiography already performed as standard care.
[PLACEHOLDER outlet]Notes from building the flow phantom rig
What we learned printing patient-specific carotid bifurcations and putting them on a pulsatile pump.
ReadWork with us
We host trainees from neurology, medical physics, computer science and engineering. Collaborations on imaging cohorts and flow modelling are always welcome.