time-of-flight MRA
Also written as: TOF-MRA — Time-of-Flight Magnetic Resonance Angiography
A non-contrast MR angiography technique that uses flowing blood signal enhancement for vascular visualization.
Full Definition
Time-of-flight magnetic resonance angiography (TOF-MRA) is a non-invasive imaging technique that generates vascular images without contrast agents by exploiting the signal differences between flowing blood and stationary tissues. Fresh blood flowing into the imaging plane appears bright due to its unsaturated spins, while stationary tissue becomes saturated and appears dark. This technique is particularly useful for evaluating intracranial vessels, carotid arteries, and other vascular territories where contrast administration may be contraindicated. TOF-MRA can be performed in 2D or 3D acquisition modes, each with specific advantages for different clinical applications.
Usage
Usage note: Specify 2D vs 3D technique and anatomical region when appropriate.
In Context
- "Time-of-flight MRA of the circle of Willis demonstrated normal flow signal in all major vessels." — Brain MRI report
- "3D TOF-MRA was performed to assess carotid bifurcation anatomy prior to endarterectomy." — Pre-operative imaging report