Utility of Low-Field Portable MRI in Neurosurgical ICU Patients Who Are Mechanically Ventilated: A Single-Center Retrospective Analysis

BACKGROUND AND PURPOSE: Conventional MRI is frequently inaccessible to neurosurgical patients who are critically ill, especially those on mechanical ventilation, because of stringent safety requirements and high-shielding needs. Low-field portable MRI presents a promising alternative by enabling bedside imaging. Nonetheless, its clinical effectiveness and diagnostic precision in these patients require further investigation. MATERIALS AND METHODS: This retrospective, single-center study included all patients who are mechanically ventilated who underwent low-field portable MRI between December 2022 and July 2024 in the neurosurgical intensive care unit. Utilizing a 0.23T low-field portable MRI (LF-pMRI) device approved by the National Medical Products Administration of China, imaging parameters and patient preparation protocols were standardized. Two senior neurosurgical intensivists and a blinded, independent neuroradiologist analyzed the MRI scans. RESULTS: Over a 20 months, 60 LF-pMRI examinations were performed on 50 patients who are mechanically ventilated, with no adverse events reported. The cohort consisted of 26 women and 24 men, with a mean age of 49.2 ± 18.7 years. LF-pMRI exhibited high sensitivity, identifying acute brain injuries in 96.7% of cases, predominantly ischemic infarctions (48.3%), followed by intracranial hemorrhage (21.7%) and infections (8.3%). Compared with CT, LF-pMRI showed superior sensitivity for postoperative infarctions (14 versus 2 detections) despite longer preparation (8.8 versus 5.6 minutes, P < .05). The system achieved 92.3% sensitivity (95% CI: 64.0–99.8) and 85.7% specificity (95% CI: 42.1–99.6) for infarction detection. LF-pMRI findings directly altered management in 38% of cases, prompting surgical interventions or therapy adjustments. CONCLUSIONS: LF-pMRI serves as a feasible and secure technique for bedside neuromonitoring in patients who are mechanically ventilated. Its proficiency in detecting critical brain abnormalities underscores its potential as a valuable complement to conventional MRI in the neurosurgical intensive care unit. Future research should concentrate on enhancing image quality and broadening its diagnostic applications.