Philip J. Allen

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The recording of electrophysiological data during BOLD fMRI is highly challenging but provides the opportunity to develop a more thorough account of brain function than either modality alone. To develop new techniques in this area has often required the study of pathological electrophysiological measures because such measures can be unusually strong (e.g.,(More)
In epilepsy patients who have electrodes implanted in their brains as part of their pre-surgical assessment, simultaneous intracranial EEG and fMRI (icEEG-fMRI) may provide important localising information and improve understanding of the underlying neuropathology. However, patient safety during icEEG-fMRI has not been addressed. Here the potential health(More)
PURPOSE To investigate heating during postimplantation localization of intracranial electroencephalograph (EEG) electrodes by MRI. MATERIALS AND METHODS A phantom patient with a realistic arrangement of electrodes was used to simulate tissue heating during MRI. Measurements were performed using 1.5 Tesla (T) and 3T MRI scanners, using head- and(More)
We investigated safety issues and potential experimental confounds when performing functional magnetic resonance imaging (fMRI) investigations in human subjects with fully implanted, active, deep brain stimulation (DBS) systems. Measurements of temperature and induced voltage were performed in an in vitro arrangement simulating bilateral DBS during magnetic(More)
PURPOSE To evaluate the usefulness of EEG-combined functional magnetic resonance imaging (EEG-fMRI) to localize epileptogenic sources. METHODS Six children (age 8-15 years) with lesional or nonlesional pharmacoresistant focal epilepsy were studied. RESULTS We found significant activations in four children, activation and deactivation in one child, and(More)
This article concerns the evaluation of the quality of interictal epileptiform EEG discharges recorded throughout simultaneous echo planar imaging (EPI). BOLD (blood oxygen level dependent) functional MRI (fMRI) images were acquired continuously on a patient with intractable epilepsy. EEG was sampled simultaneously, during and after imaging, with removal of(More)
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