The marriage of physiological data recording and magnetic resonance imaging (MRI) has allowed scientists to unravel intricate connections between the mind and body. However, this synergy comes with its unique set of challenges that researchers must be aware of to ensure the integrity of both data and the well-being of study participants.
One of the foremost challenges in recording physiological data within the MRI lab is the strong magnetic field. Traditional monitoring equipment can be rendered useless or, worse, pose extreme safety risks due to their ferromagnetic components. Another critical consideration is the impact of radiofrequency (RF) pulses used in the imaging process. RF pulses can introduce artifacts in physiological recordings, affecting the quality of data collected. In previous posts we have discussed the basics of integrating data collection in the functional MRI (fMRI) environment as well as techniques for avoiding artifacts and signal noise while recording data in the MRI.
Researchers must also contend with challenges related to the confined space and noise levels within an MRI environment. A 2021 study conducted by the Lab for Autonomic Neuroscience, Imaging and Cognition (LANIC) at Jena University Hospital in Jena, Germany, focused on how the functional MRI (fMRI) environment itself affected outcomes in autonomic research. Specifically, the study investigated the influence of a loud and cramped environment during MRI on resting heart rate variability (HRV) measures and whether a familiarization session with MRI equipment might lower anxiety levels among participants. The research team recorded an electrocardiogram (ECG) and a photoplethysmogram (PPG) over 15 minutes from participants using a BIOPAC data acquisition and analysis system connected to finger-attached PPG sensors during non-MRI recording. For recording in the fMRI, researchers used a separate BIOPAC data acquisition system equipped with an MRI-compatible PPG module. While the study did establish a link between participant anxiety and HRV levels in the lab and fMRI environment, it did not find that the familiarization sessions had a significant impact on HRV outcomes.
Despite the challenges, the recording of physiological signals in the MRI environment provides unique opportunities for gathering critical data. A study published in the journal Military Medicine in 2020 tested the effectiveness of F MRI (not to be confused with fMRI) scans in identifying cases of War Lung Injury (WLI) in Iraq and Afghanistan war veterans. WRI refers to reductions in lung function resulting from exposure to environmental factors such as sandstorms and burn pits. F MRI employs magnetic resonance imaging with perfluorinated gases as inhaled contrast agents to evaluate various pulmonary diseases. If successful, the approach would provide an alternative to surgical biopsy for diagnosis of suspected WLI. The researchers measured respiratory waveforms throughout the duration of the imaging sessions, during both normal room air breathing and PFP-oxygen gas mixture breathing using a BIOPAC magnetic resonance compatible pneumotachometer. The study found that “F MRI provides better insight regarding lung function abnormalities” than other standard methods and that “F MRI could provide a functional tool to assist in identifying subjects with the disorder and potentially could aid in the evaluation of novel therapeutic approaches.”
BIOPAC provides a wealth of tools and information resources for gathering data in the MRI environment. This includes multiple webinars on recording data in both MRI and fMRI settings. As the field continues to evolve, BIOPAC’s innovative solutions pave the way for groundbreaking discoveries at the intersection of physiological signal recording and medical imaging.
If you are interested in recording and analyzing physiological signals in your next MRI-based research study, BIOPAC sales representatives are standing by to help you choose the right tools and resources for the job.