The Magnetoencephalography Market in 2026 maintains its most clinically established and reimbursement-supported application in pre-surgical epilepsy evaluation, where MEG source analysis of spontaneously occurring interictal epileptiform discharge activity provides non-invasive localization of the irritative zone surrounding the epileptogenic focus that guides the surgical resection planning and invasive electrode placement decisions that determine the success of epilepsy surgery in achieving seizure freedom. Approximately thirty percent of epilepsy patients have drug-resistant focal epilepsy that fails to respond adequately to antiepileptic medications and may benefit from surgical resection of the seizure-generating brain region, with pre-surgical evaluation designed to precisely localize the epileptogenic zone using multiple complementary non-invasive methods including scalp video EEG, MRI structural and functional imaging, PET and SPECT functional neuroimaging, and MEG that collectively define the resection target with sufficient confidence for surgical planning. MEG provides complementary and additive localization information to scalp EEG for epileptiform discharge source analysis because MEG preferentially detects tangentially oriented cortical sources in sulcal depths where radially oriented sources from gyral crowns that dominate scalp EEG signal produce minimal MEG signal, with the complementary source orientation sensitivity of the two modalities enabling more complete cortical discharge mapping when both are analyzed together than either alone. Large retrospective studies have demonstrated that MEG source localization data changes surgical planning decisions in approximately one-third of patients compared to plans based on EEG and MRI alone, and that patients whose MEG localization is concordant with other modalities and whose surgical resection encompasses the MEG-defined irritative zone have significantly higher post-surgical seizure freedom rates than patients with discordant MEG and EEG localizations.

Magnetic source imaging, which overlays MEG source localizations on individual patient MRI structural brain images to display the spatial relationship between neural source locations and anatomical landmarks, provides neurosurgeons with the integrated three-dimensional brain mapping that most directly informs surgical approach planning, with commercial MSI software including BESA, Neuromag MaxFilter, and BrainStorm processing pipelines enabling clinical-grade source analysis that meets the evidence and documentation standards required for pre-surgical evaluation reporting. The application of advanced MEG source analysis methods including beamformer spatial filtering, dynamic imaging of coherent sources, and non-linear source analysis algorithms that go beyond conventional equivalent current dipole fitting are enabling identification of extended irritative zone networks and oscillatory connectivity patterns associated with epileptogenic networks that single dipole analysis methods cannot characterize, providing richer characterization of the epileptic network that may improve surgical target definition. Ictal MEG recording during spontaneous seizures occurring during extended MEG recording sessions provides direct seizure onset zone localization that is clinically more specific than interictal discharge mapping though technically challenging due to movement artifacts during seizure activity that advanced noise cancellation algorithms are progressively mitigating. As the pre-surgical epilepsy evaluation field continues incorporating MEG into routine multi-modality evaluation protocols and insurance reimbursement for clinical MEG expands, the epilepsy clinical application is expected to sustain its position as the primary commercial driver of the MEG market while advancing technical capabilities continue improving localization accuracy.

Do you think MEG will eventually replace some current invasive intracranial electrode monitoring in pre-surgical epilepsy evaluation for patients where non-invasive MEG localization provides sufficient certainty, or will the direct seizure recording capability of intracranial monitoring maintain its irreplaceable role in surgical planning?

FAQ

• What is the clinical pathway for MEG-based pre-surgical epilepsy evaluation and how does MEG source analysis integrate with other pre-surgical evaluation modalities? Clinical MEG for pre-surgical epilepsy evaluation typically involves a one-hour recording session during which the patient lies still in the MEG system recording spontaneously occurring interictal epileptiform discharges identified by concurrent scalp EEG monitoring that triggers artifact-free epochs for MEG source analysis, with MEG data processed through artifact rejection, signal averaging of multiple discharge events, and equivalent current dipole or distributed source analysis producing source localizations that are overlaid on patient MRI in magnetic source imaging displays, reviewed by MEG specialist neurophysiologists and neurosurgeons in multi-disciplinary surgical planning conferences alongside EEG, MRI, PET, and neuropsychological data to make concordance-based decisions about non-invasive versus invasive monitoring sufficiency for surgical target definition.
• How is the reimbursement landscape for clinical MEG structured in the United States and what documentation is required for coverage authorization? MEG clinical reimbursement in the United States uses CPT code 95965 for MEG with interpretation and report, with Medicare and commercial payer coverage generally available for pre-surgical epilepsy evaluation and pre-surgical cortical mapping indications where clinical necessity is documented through established seizure disorder diagnosis with documented drug-resistance, prior non-invasive evaluation results including EEG and MRI, and neurosurgeon or epileptologist referral documenting the planned surgical evaluation and the clinical question MEG is expected to address, with coverage less consistently available for research-only applications and some payers requiring prior authorization documentation before MEG scheduling.

#Magnetoencephalography #EpilepsySurgery #BrainMapping #PresurgicalEvaluation #NeurologyClinical #SeizureLocalization