title: EEG/(f)MRI measurements at 7 Tesla using a new EEG cap ("InkCap").
abstract: We aimed at improving the signal-to-noise ratio (SNR) of electroencephalography (EEG) during magnetic resonance imaging (MRI) by introducing a new EEG cap ("InkCap") based on conductive ink technology. The InkCap was tested with temperature measurements on an electrically conductive phantom head and during structural and functional MRI (fMRI) recordings in 11 healthy human volunteers at 7 T. Combined EEG/fMRI measurements were conducted to study the interaction between the two modalities. The EEG recordings with the InkCap demonstrated up to a five-fold average decrease in signal variance during echo-planar imaging, with respect to a cap made of standard carbon fiber leads. During concurrent EEG/fMRI measurements in human volunteers, alpha oscillations were clearly detected at 7 T. Minimal artifacts were present in the T2* and high-resolution structural MR images of the brain parenchyma. Our results show that the InkCap technology considerably improves the quality of both EEG and (f)MRI during concurrent measurements even at 7 T.
authors.affiliation: Harvard Medical School, Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Building 149, 13th Street, Charlestown 02129, USA. cvasios@nmr.mgh.harvard.edu
authors.forename: Christos E
authors.initials: CE
authors.lastname: Vasios
authors.forename: Leonardo M
authors.initials: LM
authors.lastname: Angelone
authors.forename: Patrick L
authors.initials: PL
authors.lastname: Purdon
authors.forename: Jyrki
authors.initials: J
authors.lastname: Ahveninen
authors.forename: John W
authors.initials: JW
authors.lastname: Belliveau
authors.forename: Giorgio
authors.initials: G
authors.lastname: Bonmassar
mesh_terms: D000328:Adult; D004569:Electroencephalography / Q000295:instrumentation*; D004867:Equipment Design; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods