MIRACLES
The Hyperfine Swoop MRI (Magnetic Resonance Imaging) Scanner is a small, portable ultra-low field MRI scanner. It has been designed to provide neuroimaging at the patients’ bedside.
The MIRACLES project, led by Prof Keith Muir, will investigate the use of this point of care MRI scanner in the investigation of acute stroke patients. Imaging of the brain is central to the management of acute stroke and transient ischaemic attack. The key roles for imaging include confirming diagnosis, determining treatment eligibility, indicating probable mechanism, informing prognosis, and identifying complications of stroke or its treatment. Magnetic Resonance Imaging (MRI), particularly the Diffusion weighted imaging (DWI) sequence, is particularly suited to this role since it is highly sensitive to changes in brain water distribution that are not readily visualised on X-ray based computed tomography (CT) in the first hours after onset of ischaemia.
Factors that limit access to MRI include the need for patient compatibility checks for metal implants or devices that are incompatible with the high magnetic fields used in routine clinical MRI, difficulty in monitoring unwell patients in the MRI scanner environment, and poor tolerability of the limited space that may lead to claustrophobia and non-diagnostic images since image acquisition times are typically 15-30 minutes for a complete examination. Hyperfine have designed the Swoop system to address these limitations by producing a low magnetic field (0.064 Tesla) with technology that monitors electromagnetic fields in the surrounding environment to cancel out background interference typical of a clinical setting.
This prospective observational study will evaluate the potential value of mobile MRI in patients with suspected or proven acute stroke and TIA, undertaking additional imaging in the emergency department and comparing diagnostic accuracy and DWI lesion volume. Information on ease of use, tolerability and image quality will also be gathered.