98%
921
2 minutes
20
Objective: Stereoelectroencephalography (SEEG) is designed to target distributed cortical networks responsible for electroclinical seizure syndrome and to enable localization of the site of seizure onset in patients with intractable epilepsy. When the preimplantation hypothesis invokes the bilateral mesial frontal lobes, sampling of several deep-seated cortical sites in both hemispheres is required. In this study, the authors have demonstrated the feasibility of sampling bihemispheric areas with intentional implantation of an SEEG electrode crossing the midline (SECM) for sampling the cortex on both sides of the interhemispheric fissure.
Methods: An analysis of 231 consecutive SEEG procedures over 8 years was used to identify instances of bihemispheric sampling by using the transmidline SEEG technique.
Results: The authors identified 53 SEEG cases, with a total of 126 electrodes that crossed the interhemispheric fissure; all were in the frontal lobes. Eighty-three electrodes targeted the cingulate gyrus (18 rostral, 43 anterior, and 22 middle), 31 targeted the posterior orbitofrontal region, 8 sampled the medial prefrontal cortex, and 4 targeted nodular heterotopia around the frontal horns. The ictal onset zone was localized to the frontal lobe in 16 cases. SECM isolated interictal and ictal activity in the contralateral hemisphere in 6 cases and independent bihemispheric seizure activity in 2 cases. No hemorrhagic or infectious complications were noted in any of these cases.
Conclusions: Based on this extensive experience of bihemispheric sampling, the authors concluded that this technique is safe and effective. In this series, SECM showed contralateral interictal and/or ictal epileptiform activity in 8 (15%) cases, and 9 (16%) cases (with unilateral implantation) had sufficient data to discard contralateral involvement, contributing to support of the epileptogenic network. SECM may reduce the number of electrodes used to sample bilateral mesial frontal or orbitofrontal cortices, and such an approach may lower the risk of hemorrhage and costs.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.3171/2022.11.JNS221144 | DOI Listing |
Brain
September 2025
Center for Brain Plasticity and Recovery, Center for Aphasia Research and Rehabilitation, Departments of Neurology and Rehabilitation Medicine, Georgetown University Medical Center, Washington, DC, 20057 USA.
The role of the right hemisphere in aphasia recovery has been controversial since the 19th century. Imaging studies have sometimes found increased activation in right hemisphere regions homotopic to canonical left hemisphere language regions, but these results have been questioned due to small sample sizes, unreliable imaging tasks, and task performance confounds that affect right hemisphere activation levels even in neurologically healthy adults. Several principles of right hemisphere language recruitment in aphasia have been proposed based on these studies: that the right hemisphere is recruited primarily by individuals with severe left hemisphere damage, that transcallosal disinhibition results in recruitment of right hemisphere regions homotopic to the lesion, and that increased right hemisphere activation diminishes to baseline levels over time.
View Article and Find Full Text PDFEat Weight Disord
August 2025
Global Digital Wellbeing Program (Sync), King Abdulaziz Center for World Culture (Ithra), Dhahran, Saudi Arabia.
Purpose: Seasonal body image refers to within-person variations in body image satisfaction that correspond with climatic seasonality (winter, spring, summer, and autumn). Previous cross-sectional research involving male participants from northern (UK, USA, and Canada) and southern hemisphere (Australia) nations reports a peak in body image dissatisfaction during the summertime, with a decrease in the wintertime. Big Data extracted from social media platforms provides a novel means of further exploring the seasonal body image hypothesis in a larger and more diverse sample across several years.
View Article and Find Full Text PDFmedRxiv
April 2025
Center for Brain Plasticity and Recovery, Center for Aphasia Research and Rehabilitation, Departments of Neurology and Rehabilitation Medicine, Georgetown University Medical Center, Washington, DC, USA.
The role of the right hemisphere in aphasia recovery has been controversial since the 19th century. Imaging studies have sometimes found increased activation in right hemisphere regions homotopic to canonical left hemisphere language regions, but these results have been questioned due to small sample sizes, unreliable imaging tasks, and task performance confounds that affect right hemisphere activation levels even in neurologically healthy adults. Several principles of right hemisphere language recruitment in aphasia have been proposed based on these studies: that the right hemisphere is recruited primarily by individuals with severe left hemisphere damage, that transcallosal disinhibition results in recruitment of right hemisphere nodes homotopic to the lesion, and that increased right hemisphere activation diminishes to baseline levels over time.
View Article and Find Full Text PDFMedicina (Kaunas)
August 2024
Department 6-Clinical Neurosciences, Division of Neurosurgery, Faculty of Medicine, "Carol Davila" University of Medicine and Pharmacy, RO-020021 Bucharest, Romania.
Epilepsia
July 2024
Department of Neurology, University of Chicago, Chicago, Illinois, USA.