Invasive pressure monitoring of patients during magnetic resonance imaging.

The purpose of this paper is to describe a system for monitoring patients who require general anaesthesia, profound sedation or intensive care while undergoing high field (> or = 1.5 T) magnetic resonance (MR) imaging. Continuous evaluation of invasive and noninvasive pressures, inspired and end-tidal respiratory gas concentrations, body temperature, heart rate, ECG and pulse oximetry were measured successfully during the MR examination. Diagnostic quality MR images were acquired on all 15 monitored patients. The calculated signal-to-noise ratios were not different between the control and monitored patients. Commonly encountered technical problems and their solutions are described. This study demonstrates that invasive monitoring can be safely performed in critically ill patients who are undergoing high field MR examinations.