Source localization of interictal spikes in patients with medically refractory epilepsy is the most common clinical application of magnetoencephalography (MEG). In recent decades, many patients with intractable epilepsy have been treated with various forms of neurostimulation, including thalamic deep brain stimulation (DBS). Patients with suboptimal seizure control after DBS might in some cases benefit from further investigations for resective epilepsy surgery, including MEG source imaging (MSI). We sought to determine the feasibility and accuracy of MSI in the setting of active thalamic DBS. Simultaneous EEG/MEG was obtained in a patient using an Elekta 306-channel MEG system, with high-frequency (100 Hz) DBS of the thalamic anterior nuclei cycling between on and off states. Magnetic artifacts associated with the DBS apparatus were successfully suppressed using the spatiotemporal signal space separation (tSSS) method. Electrical stimulation artifact was removed by standard digital low-pass filtering. Dipole source modeling results for spike foci in frontal and posterior temporal regions were comparable between stimulation on and stimulation off states, and the source solutions corresponded well to the localization of spikes documented by intracranial EEG. MSI is thus feasible and source solutions can be accurate when performed in patients with active thalamic DBS for epilepsy.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5939388 | PMC |
http://dx.doi.org/10.1002/epi4.12027 | DOI Listing |
Invest Radiol
January 2025
From the Departments of Radiology (J.F.H., S.Y.C., J.-P.G., J.S., P.N., S.B.R., T.M.G.), Biomedical Engineering (S.B.R., T.M.G.), Medical Physics (S.Y.C., S.B.R., T.M.G.), Medicine (S.B.R.), and Emergency Medicine (S.B.R.), University of Wisconsin-Madison, WI; and Department of Diagnostic and Interventional Radiology (J.F.H., J.-P.G.), University Hospital Würzburg, Würzburg, Germany.
Rationale And Objectives: Pulmonary magnetic resonance angiography (MRA) is an imaging method with proven utility for the exclusion of pulmonary embolism and avoids the need for ionizing radiation and iodinated contrast agents. High-relaxivity gadolinium-based contrast agents (GBCAs), such as gadopiclenol, can be used to reduce the required gadolinium dose for pulmonary MRA. The aim of this study was to compare the contrast enhancement performance of gadopiclenol with an established gadobenate dimeglumine-enhanced pulmonary MRA protocol.
View Article and Find Full Text PDFInvest Radiol
January 2025
From the Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany (A. Schwarz, A. Simon, A.M.); Siemens Healthineers AG, Forchheim, Germany (A. Schwarz, C.H., J.D., A. Simon); Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany (F.K.W., S.G., M.S.); and Institut for Radiology, Pediatric and Neuroradiology, Helios Hospital, Schwerin, Germany (H.-J.R.).
Objective: Respiratory motion can affect image quality and thus affect the diagnostic accuracy of CT images by masking or mimicking relevant lung pathologies. CT examinations are often performed during deep inspiration and breath-hold to achieve optimal image quality. However, this can be challenging for certain patient groups, such as children, the elderly, or sedated patients.
View Article and Find Full Text PDFScience
January 2025
Wolfson Catalysis Centre, Department of Chemistry, University of Oxford, Oxford, UK.
The distribution of substitutional aluminum (Al) atoms in zeolites affects molecular adsorbate geometry, catalytic activity, and shape and size selectivity. Accurately determining Al positions has been challenging. We used synchrotron resonant soft x-ray diffraction (RSXRD) at multiple energies near the Al K-edge combined with molecular adsorption techniques to precisely locate "single Al" and "Al pairs" in a commercial H-ZSM-5 zeolite.
View Article and Find Full Text PDFRadiographics
February 2025
From the Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Ave, Boston, MA 02215.
Nonpregnant and pregnant women who present with acute pelvic pain can pose a diagnostic challenge in the emergency setting. The clinical presentation is often nonspecific, and the differential diagnosis may be very broad. These symptoms are often indications for pelvic US, which is the primary imaging modality when an obstetric or gynecologic cause is suspected.
View Article and Find Full Text PDFJASA Express Lett
January 2025
Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093,
This work demonstrates the feasibility of performing through-the-sensor (TTS) sub-bottom imaging using low-frequency ([100 Hz-1kHz]) self-noise generated by the propulsion of an autonomous underwater vehicle (AUV) acting as a source of opportunity. The self-noise was recorded by a short towed horizontal line array (11.4 m aperture) by the same AUV while it operated ∼35 m above the seabed along a range-dependent section at the New England shelf break.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!