Page 189 - MEGIN Book Of Abstracts - 2023

METHODS Twenty-five clinical MEG centers were in- Michigan University, Ypsilanti, Michigan, U.S.A
vited to participate anonymously in a survey of clinical
practice. ABSTRACT Numerous studies have shown that lan-
guage processing is not limited to a few brain areas.
RESULTS Centers (N = 18) mostly operated within an Visual or auditory stimuli activate corresponding corti-
academic medical center (10/18), were owned by the cal areas, then memory identifies the word or image,
"hospital" (10/18), associated with a level 4 National Wernicke's and Broca's areas support the processing for
Association of Epilepsy center (15/18), and directed either reading/listening or speaking and many areas
by neurologists (10/18). A total of 873 (median 59) of the brain are recruited. Determining how a normal
epilepsy studies, 1,179 evoked fields (of all types), and person processes language helps clinicians and scien-
1,607 (median 30) research MEG studies were reported. tist to understand how brain pathologies such as tumor
Fourteen of 17 centers serve children (median 35%), or stroke can affect changes in language processing.
but only 5 of 14 sedate children for MEG. All (N = 14) Patients with epilepsy may develop atypical language
centers record EEG simultaneous with MEG, and 57% organization. Over time, the chronic nature of epileptic
used dipole source localization. The median reporting activity, or changes from a tumor or stroke, can result in
time for epilepsy studies was 12 and 10 days for pre- a shift of language processing area from the left to the
surgical mapping studies. Most (12/14) were favorable right hemisphere, or re-routing of language pathways
toward the Clinical Practice Guidelines and "formalized from traditional to non-traditional areas within the
certification" but were against mandating the latter. dominant left hemisphere. It is important to determine
where these language areas are prior to brain surgery.
CONCLUSIONS A plateau in MEG volumes suggests MEG evoked responses reflecting cerebral activa-
that MEG has not become a part of the standard of tion of receptive and expressive language processing
care, and correspondingly, the Clinical Practice Guide- can be localized using several different techniques:
lines appeared to have had little impact on clinical Single equivalent current dipole, current distribution
practice. The American Clinical Magnetoencephalogra- techniques or beamformer techniques. Over the past
phy Society must continue to engage magnetoenceph- 20 years there have been at least 25 validated MEG
alographers, potential referrers, and vendors. studies that indicate MEG can be used to determine the
dominant hemisphere for language processing. The use
Journal of clinical neurophysiology: official publication of MEG neuroimaging techniques is needed to reliably
of the American Electroencephalographic Society (2020), predict altered language networks in patients and to
Vol. 37, No. 6 (33165232) (11 citations) provide identification of language eloquent cortices for
localization and lateralization necessary for clinical care.

Language Mapping With Magnetoencephalography: Journal of clinical neurophysiology: official publication
An Update on the Current State of Clinical Research of the American Electroencephalographic Society (2020),
and Practice With Considerations for Clinical Vol. 37, No. 6 (33165228) (12 citations)
Practice Guidelines (2020)

Bowyer, Susan M; Zillgitt, Andrew; Greenwald, MEG Reporting (2020)
Margaret; Lajiness-O'Neill, Renee
Burgess, Richard C
Department of Physics, Oakland University, Rochester, Michi-
gan, U.S.A; Department of Neurology, Henry Ford Health Sys- Cleveland Clinic Epilepsy Center, Cleveland, Ohio, U.S.A
tem, Detroit, Michigan, U.S.A; Department of Communica-
tion Sciences and Disorders, Wayne State University, Detroit, ABSTRACT The report generated by the magnetoen-
Michigan, U.S.A.; and; Department of Psychology, Eastern cephalographer's interpretation of the patient's mag-

 ontents  Index 168
C