Human "memories" can be evoked by stimulation of the lateral temporal cortex after ipsilateral medial temporal lobe resection

OBJECTIVEIn drug-resistant temporal lobe epilepsy (TLE) patients, the authors evaluated early and late outcomes for decline in visual object naming after dominant temporal lobe resection (TLR) according to the resection status of the basal temporal language area (BTLA) identified by cortical stimulation during stereoelectroencephalography (SEEG).METHODSTwenty patients who underwent SEEG for drug-resistant TLE met the inclusion criteria. During language mapping, a site was considered positive when stimulation of two contiguous contacts elicited at least one naming impairment during two remote sessions. After TLR ipsilateral to their BTLA, patients were classified as BTLA+ when at least one positive language site was resected and as BTLA− when all positive language sites were preserved. Outcomes in naming and verbal fluency tests were assessed using pre- and postoperative (means of 7 and 25 months after surgery) scores at the group level and reliable change indices (RCIs) for clinically meaningful changes at the individual level.RESULTSBTLA+ patients (n = 7) had significantly worse naming scores than BTLA− patients (n = 13) within 1 year after surgery but not at the long-term evaluation. No difference in verbal fluency tests was observed. When RCIs were used, 5 of 18 patients (28%) had naming decline within 1 year postoperatively (corresponding to 57% of BTLA+ and 9% of BTLA− patients). A significant correlation was found between BTLA resection and naming decline.CONCLUSIONSBTLA resection is associated with a specific and early naming decline. Even if this decline is transient, naming scores in BTLA+ patients tend to remain lower compared to their baseline. SEEG mapping helps to predict postoperative language outcome after dominant TLR.

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Review for "Early volumetric changes of hippocampus and medial prefrontal cortex following medial temporal lobe resection"

10.1111/ejn.14784/v1/review1 ◽

2020 ◽

Author(s):

Michele Porcu

Keyword(s):

Prefrontal Cortex ◽

Medial Prefrontal Cortex ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Temporal Lobe Resection

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Simultaneous Electroencephalographic and Electocorticographic Recordings of Lateralized Periodic Discharges in Temporal Lobe Epilepsy

Clinical EEG and Neuroscience ◽

10.1177/1550059420972266 ◽

2020 ◽

pp. 155005942097226

Author(s):

Ayumi Sakata ◽

Nobutaka Mukae ◽

Takato Morioka ◽

Shunya Tanaka ◽

Takafumi Shimogawa ◽

...

Keyword(s):

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Chronic Conditions ◽

Medial Temporal Lobe ◽

Temporal Cortex ◽

Temporal Region ◽

Pathophysiological Mechanism ◽

Periodic Discharges ◽

Pathological Conditions ◽

Eeg Pattern

Objective Lateralized periodic discharges (LPDs), which constitute an abnormal electroencephalographic (EEG) pattern, are most often observed in critically ill patients with acute pathological conditions, and are less frequently observed in chronic conditions such as focal epilepsies, including temporal lobe epilepsy (TLE). Here we aim to explore the pathophysiological mechanism of LPD in TLE. Methods We retrospectively selected 3 patients with drug-resistant TLE who simultaneously underwent EEG and electrocorticography (ECoG) and demonstrated LPDs. We analyzed the correlation between the EEG and ECoG findings. Results In patients 1 and 2, LPDs were recorded in the temporal region of the scalp during the interictal periods, when repeated spikes followed by slow waves (spike-and-wave complexes; SWs) and periodic discharges (PDs) with amplitudes of >600 to 800 µV appeared in the lateral temporal lobe over a cortical area of >10 cm2. In patient 3, when the ictal discharges persisted and were confined to the medial temporal lobe, repeated SWs were provoked on the lateral temporal lobe. When repeated SWs with amplitudes of >800 µV appeared in an area of the lateral temporal lobe of >10 cm2, the corresponding EEG discharges appeared on the temporal scalp. Conclusions LPDs in patients with TLE originate from repeated SWs and PDs of the lateral temporal lobe, which might represent a highly irritable state of the lateral temporal cortex during both interictal and ictal periods.

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Distinct Cortical Anatomy Linked to Subregions of the Medial Temporal Lobe Revealed by Intrinsic Functional Connectivity

Journal of Neurophysiology ◽

10.1152/jn.00077.2008 ◽

2008 ◽

Vol 100 (1) ◽

pp. 129-139 ◽

Cited By ~ 288

Author(s):

Itamar Kahn ◽

Jessica R. Andrews-Hanna ◽

Justin L. Vincent ◽

Abraham Z. Snyder ◽

Randy L. Buckner

Keyword(s):

Functional Connectivity ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Temporal Cortex ◽

Memory System ◽

Retrosplenial Cortex ◽

The Body ◽

Parallel Pathways ◽

Ventral Medial Prefrontal Cortex ◽

Adjacent Structures

The hippocampus and adjacent cortical structures in the medial temporal lobe (MTL) contribute to memory through interactions with distributed brain areas. Studies of monkey and rodent anatomy suggest that parallel pathways converge on distinct subregions of the MTL. To explore the cortical areas linked to subregions of the MTL in humans, we examined cortico-cortical and hippocampal-cortical correlations using high-resolution, functional connectivity analysis in 100 individuals. MTL seed regions extended along the anterior to posterior axis and included hippocampus and adjacent structures. Results revealed two separate brain pathways that correlated with distinct subregions within the MTL. The body of the hippocampus and posterior parahippocampal cortex correlated with lateral parietal cortex, regions along the posterior midline including posterior cingulate and retrosplenial cortex, and ventral medial prefrontal cortex. By contrast, anterior hippocampus and the perirhinal/entorhinal cortices correlated with distinct regions in the lateral temporal cortex extending into the temporal pole. The present results are largely consistent with known connectivity in the monkey and provide a novel task-independent dissociation of the parallel pathways supporting the MTL memory system in humans. The cortical pathways include regions that have undergone considerable areal expansion in humans, providing insight into how the MTL memory system has evolved to support a diverse array of cognitive domains.

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The effect of electrical stimulation of medial temporal lobe structures in epileptic patients upon ACTH, prolactin, and growth hormone

Neurology ◽

10.1212/wnl.37.2.299 ◽

1987 ◽

Vol 37 (2) ◽

pp. 299-299 ◽

Cited By ~ 34

Author(s):

B. B. Gallagher ◽

H. F. Flanigin ◽

D. W. King ◽

W. H. Littleton

Keyword(s):

Growth Hormone ◽

Electrical Stimulation ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Epileptic Patients ◽

Stimulation Of

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Decision-making impairments following insular and medial temporal lobe resection for drug-resistant epilepsy

Social Cognitive and Affective Neuroscience ◽

10.1093/scan/nsw152 ◽

2016 ◽

pp. nsw152 ◽

Cited By ~ 3

Author(s):

Zorina Von Siebenthal ◽

Olivier Boucher ◽

Isabelle Rouleau ◽

Maryse Lassonde ◽

Franco Lepore ◽

...

Keyword(s):

Decision Making ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Drug Resistant ◽

Temporal Lobe Resection ◽

Drug Resistant Epilepsy

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Stimulation of the human medial temporal lobe between learning and recall selectively enhances forgetting

Brain Stimulation ◽

10.1016/j.brs.2016.12.011 ◽

2017 ◽

Vol 10 (3) ◽

pp. 645-650 ◽

Cited By ~ 18

Author(s):

Maxwell B. Merkow ◽

John F. Burke ◽

Ashwin G. Ramayya ◽

Ashwini D. Sharan ◽

Michael R. Sperling ◽

...

Keyword(s):

Temporal Lobe ◽

Medial Temporal Lobe ◽

Stimulation Of

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Access to the Posterior Medial Temporal Lobe Structures in the Surgical Treatment of Temporal Lobe Epilepsy

Neurosurgery ◽

10.1227/00006123-198411000-00005 ◽

1984 ◽

Vol 15 (5) ◽

pp. 667-671 ◽

Cited By ~ 298

Author(s):

Dennis D. Spencer ◽

Susan S. Spencer ◽

Richard H. Mattson ◽

Peter D. Williamson ◽

Robert A. Novelly

Keyword(s):

Temporal Lobe ◽

Medial Temporal Lobe ◽

Temporal Cortex ◽

En Bloc Resection ◽

Bloc Resection ◽

En Bloc ◽

Visual Spatial ◽

Temporal Horn ◽

Inferior Longitudinal Fasciculus ◽

Complex Partial Epilepsy

Abstract The authors describe a surgical technique that allows access to the posterior temporal horn of the lateral ventricle with preservation of the most functional lateral temporal cortex. Development of the technique was stimulated by the need to resect posteromedial temporal lobe structures in patients with intractable complex partial epilepsy and well-identified unilateral posterior hippocampal foci. This technique has also been of value in the resection of some lateral ventricular and posteromedial temporal lobe masses. The operation consists of three steps. No more than 4.5 cm of the anterolateral temporal lobe is removed en bloc such that the most anterior aspect of the temporal horn is entered. An incision is carried from the floor of the temporal horn through the inferior longitudinal fasciculus to the middle fossa dura mater and posteriorally into the lateral ventricular atrium. The lateral temporal cortex and white matter are then elevated with a self-retaining retractor. This exposes the posteromedial temporal horn or intraaxial mass for excision or allows en bloc resection of the entire hippocampus and medial temporal lobe structures while preserving the functional association areas of the lateral temporal cortex, including speech and visual spatial function.

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Left Transsylvian Transcisternal and Transinferior Insular Sulcus Approach for Resection of Uncohippocampal Tumor: 3-Dimensional Operative Video

Operative Neurosurgery ◽

10.1093/ons/opy106 ◽

2018 ◽

Vol 15 (6) ◽

pp. E79-E80 ◽

Cited By ~ 1

Author(s):

Juan C Fernandez-Miranda

Keyword(s):

Temporal Lobe ◽

Medial Temporal Lobe ◽

Anterior Segment ◽

Temporal Cortex ◽

Surgical Anatomy ◽

Temporal Lobectomy ◽

Temporal Region ◽

3 Dimensional ◽

Selective Amygdalohippocampectomy ◽

Selective Approach

Abstract The medial temporal lobe can be divided in anterior, middle, and posterior segments. The anterior segment is formed by the uncus and hippocampal head, and it has extra and intraventricular structures. There are 2 main approaches to the uncohippocampal region, the anteromedial temporal lobectomy (Spencer's technique) and the transsylvian selective amygdalohippocampectomy (Yasargil's technique). In this video, we present the case of a 29-yr-old man with new onset of generalized seizures and a contrast-enhancing lesion in the left anterior segment of the medial temporal lobe compatible with high-grade glioma. He had a medical history of cervical astrocytoma at age 8 requiring craniospinal radiation therapy and ventriculoperitoneal shunt placement. The tumor was approached using a combined transsylvian transcisternal and transinferior insular sulcus approach to the extra and intraventricular aspects of the uncohippocampal region. It was resected completely, and the patient was neurologically intact after resection with no further seizures at 6-mo follow-up. The diagnosis was glioblastoma IDH-wild type, for which he underwent adjuvant therapy. Surgical anatomy and technical nuances of this approach are illustrated using a 3-dimensional video and anatomic dissections. The selective approach, when compared to an anteromedial temporal lobectomy, has the advantage of preserving the anterolateral temporal cortex, which is particularly relevant in dominant-hemisphere lesions, and the related fiber tracts, including the inferior fronto-occipital and inferior longitudinal fascicles, and most of the optic radiation fibers. The transsylvian approach, however, is technically and anatomically more challenging and potentially carries a higher risk of vascular injury and vasospasm. Page 1 and figures from Fernández-Miranda JC et al, Microvascular Anatomy of the Medial Temporal Region: Part 1: Its Application to Arteriovenous Malformation Surgery, Operative Neurosurgery, 2010, Volume 67, issue 3, ons237-ons276, by permission of the Congress of Neurological Surgeons (1:26-1:37 in video). Page 1 from Fernández-Miranda JC et al, Three-Dimensio-nal Microsurgical and Tractographic Anatomy of the White Matter of the Human Brain, Neurosurgery, 2008, Volume 62, issue suppl_3, SHC989-SHC1028, by permission of the Congress of Neurological Surgeons (1:54-1:56 in video).

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