Portable MRI Scanners Can Be Used at Bedside to Evaluate Stroke

May 5, 2020
By Alex Morrisson WEST PALM BEACH, Fla -- May 4, 2020 -- A low-field MRI scanner is feasible for use at the bedside of patients exhibiting symptoms of stroke, according to a study presented at the 2020 Virtual Meeting of the American Academy of Neurology (AAN). Kevin Sheth, MD, Yale School of Medicine, New Haven, Connecticut, reported that point-of-care MRI was obtained in 85 stroke cases (age, 18-96 years; 46% female). The bedside MRI was used to diagnose ischaemic stroke in 46% of cases, intracerebral haemorrhage in 34% of cases, and in subarachnoid haemorrhage in 20% of cases. In the study, the bedside scan results correlated with standard imaging. “We are reporting the first use of a portable, low-field MRI system to image stroke patients at the bedside,” he said. “This early work suggests our approach is safe and viable in a complex clinical care environment. Conventionally, patients must travel to the location of a high-field MRI device for stroke neuroimaging. Advances in low-field MRI have enabled acquisition of clinically useful images using a portable device at the bedside.” The examinations were performed in Yale’s Neuroscience Intensive Care Unit from July 2018 to August 2019. Images were acquired at the bedside using a standard 110V, 15A power outlet. The environment included monitors, ventilators, and intravenous infusion pumps. Exams were performed by research staff trained to operate the scanner in the absence of an MRI technician. Ferrous metals remained in the room. Scan parameters were controlled using a tablet computer interface, and images were available immediately. “To date, the scans have been under an investigational protocol but not used by trained technicians,” said Dr. Sheth. “Post-graduate researchers with no other technical training have been able to perform scans, so that is a big advantage. Time will tell, but our preliminary results suggest that the scanner could be deployed in locations and with frequency that will be a benefit to all.” Scans were obtained within 7 days of symptom onset. Of the 85 patients, 74 were able to complete the examination. Five patients were unable to fit in the scanner’s 30 cm opening and 6 patients experienced claustrophobia resulting in early termination of the exam. The mean exam time was 28.9 minutes. [Presentation title: Deployment of Portable, Bedside, Low-Field Magnetic Resonance Imaging for Evaluation of Stroke Patients. Abstract 272]