Optically Pumped Magnetometers versus Cryogenic Magnetoencephalography in the Detection of Interictal Epileptic Discharges and Signal-to-noise Ratio
Abstract number :
2.489
Submission category :
3. Neurophysiology / 3D. MEG
Year :
2024
Submission ID :
1626
Source :
www.aesnet.org
Presentation date :
12/8/2024 12:00:00 AM
Published date :
Authors :
Presenting Author: Jiechuan Ren, MD – Department of Neurology, Beijing Tiantan Hospital, Capital Medical University
Yuming Peng, PhD – School of Instrumentation and Optoelectronic Engineering, Beihang University, China
Chang Sun, PhD – School of Instrumentation and Optoelectronic Engineering, Beihang University, China
Chunqing Yang, BS – Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, China
Qun Wang, MD – Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, China
Ming Ding, PhD – School of Instrumentation and Optoelectronic Engineering, Beihang University, China
Zhimei Li, MD – Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, China
Rationale: Magnetoencephalography (MEG) is an important tool for the detection and localization of epileptic spikes. Conventional MEG systems are based on Superconducting Quantum Interference Devices (SQUID), which is cryogenic and demands high maintaining cost because of the use of liquid helium. Also, the thermal isolation space between the SQUID sensors and cerebral cortex significantly reduces the signal-to-noise ratio (SNR). The new generation Optically Pumped Magnetometers (OPM) MEG system is free of liquid helium, thus largely reduces maintenance costs. The decreased distance to cortex could elevate the SNR. The OPM MEG system could overcome the limitations of conventional SQUID MEG systems and may have more widespread clinical and research potential. In this research, we aim to examine the potential benefits of interictal epileptic discharges (IEDs) detection SNR in OPM MEG over SQUID MEG in real-world epilepsy patients.
Methods: 21 refractory focal epilepsy patients from the Epilepsy Center of Beijing Tiantan Hospital were enrolled. SQUID MEG (Neuromag TRIUX，MEGIN) and OPM MEG (Marvel MEG, Beijing X-Magtech Medical Technologies Limited) were performed separately in each patients in similar conditions. IEDs of the two systems were identified independently. We used t-test to compare the SNRs of two MEG systems. P value less than 0.05 is considered statistically significant.
Results: Among the 21 refractory focal epilepsy patients, 9 were female. The median age was 35 years (range 8-50 years). IEDs were detected in all patients in both MEG systems. The averaged IEDs SNR of OPM MEG was 10.74±3.62, and that of SQUID MEG was 9.31±4.30. P value of t-test is 0.035, showing the IEDs SNR of OPM MEG is significantly higher than that of SQUID MEG.
Conclusions: This research shows that OPM MEG had comparable IEDs detection ability with that of SQUID MEG. Whereas OPM MEG has higher SNR than SQUID MEG in the detection of IEDs in real-world epilepsy patients. As OPM MEG has much lower economic cost, this new generation MEG system has more widespread clinical prospect.
Funding: National Key R and D Program of China (2022YFC2403905)
Neurophysiology