Clinical significance of intraoperative bidirectional corticocortical evoked potential monitoring to evaluate language function.

Objective: Awake craniotomy is commonly used to resect lesions located near the language area during brain surgery. However, it is often difficult to perform language tasks due to several limitations such as difficulty in awakening during surgery and intraoperative seizures. This study investigated the clinical significance of bidirectional corticocortical evoked potential (CCEP) monitoring as a new approach to evaluate intraoperative language function.

Congenital extraventricular neurocytoma with atypical features in a 3-day-old neonate.

Extraventricular neurocytoma (EVN) is a rare neuronal tumor with a marked tendency towards ganglionic or glial differentiation. Although EVN commonly occurs in young adults, congenital cases are extremely rare, and standardized therapeutic strategies remain undetermined. The presence of atypical features such as increased mitotic activity on histological analysis is correlated with a higher rate of recurrence and poor prognosis.

A Case of Subdural Hygroma due to a Ruptured Arachnoid Cyst in the Middle Cranial Fossa That Improved after Long-term Subdural Drainage: A Case Report and Review of the Literature.

Arachnoid cysts have the potential to rupture, leading to the development of a subdural hygroma following minor trauma. Although surgery may be considered in cases of increased intracranial pressure (ICP) or regional neurological symptoms, the optimal approach remains unclear. We report a case of subdural hygroma due to a ruptured arachnoid cyst (SHrAC) with elevated ICP successfully treated with long-term subdural drainage for over 1 month.

Unpleasant thoughts and anxiety induced by electrical cortical stimulation.

Emotional processing has been attracting increased attention. We herein present three patients with intractable epilepsy in whom emotional responses were elicited by electrical cortical stimulation. Negative feelings were produced in all patients; however, the content of each differed.

Deep learning from head CT scans to predict elevated intracranial pressure.

Background And Purpose: Elevated intracranial pressure (ICP) resulting from severe head injury or stroke poses a risk of secondary brain injury that requires neurosurgical intervention. However, currently available noninvasive monitoring techniques for predicting ICP are not sufficiently advanced. We aimed to develop a minimally invasive ICP prediction model using simple CT images to prevent secondary brain injury caused by elevated ICP.

Neurosarcoidosis Complicated by Noncommunicating Hydrocephalus with Atypical Presentation, Diagnosed and Treated with Endoscopic Surgery: A Case Report.

Neurosarcoidosis is a condition that is characterized by the occurrence of noncaseating epithelioid granulomas in various organs throughout the body, including the lungs, heart, and central nervous system. It is particularly prevalent in cases of noncommunicating hydrocephalus. While its clinical presentations may vary, neurological deficits such as hemiparesis are extremely uncommon.

An anatomo-functional study of the interactivity between the paracentral lobule and the primary motor cortex.

Objective: The purpose of this study was to understand the anatomical and functional connections between the paracentral lobule (PCL) and the primary motor cortex (M1) of the human brain.

Methods: This retrospective study included 16 patients who underwent resection of lesions located near M1. Nine patients had lesions in the dominant hemisphere.

[Usefulness of Preoperative Simulation: Skull Base Approach].

Preoperative simulation images creates an accurate visualization of a surgical field. The anatomical relationship of the cranial nerves, arteries, brainstem, and related bony protrusions is important in skull base surgery. However, an operator's intention is unclear for a less experienced neurosurgeon.

Combined endoscopic endonasal and transcranial approach for internal carotid artery aneurysms: usefulness and safety of endonasal proximal control.

It is necessary to secure both the proximal and distal sides of the parent artery to prevent premature rupture when clipping cerebral aneurysms. Herein, we describe four cases in which the proximal internal carotid artery (ICA), affected by a paraclinoid aneurysm, was secured using an endoscopic endonasal approach. We used various tools, including a surgical video, cadaver dissection picture, artist's illustration, and intraoperative photographs, to elucidate the process.

Intraoperative nerve stimulation during vagal nerve stimulator placement.

Background: Vagal nerve stimulation (VNS) is a palliative treatment for refractory epilepsy and intraoperative nerve stimulation is applied to the vagal and other nerves to prevent electrode misplacement. We evaluated these thresholds to establish intraoperative monitoring procedures for VNS surgery.

Methods: Forty-six patients who underwent intraoperative nerve stimulation during VNS placement were enrolled.

Effect of a Low Concentration of Sevoflurane Combined With Propofol on Transcranial Electrical Stimulation Motor Evoked Potential: A Case Series.

Transcranial electrical motor evoked potential (TCeMEP) is used to monitor the integrity of intraoperative motor function. Total intravenous anesthesia (TIVA) is the preferred method because its effect on MEP is relatively smaller than volatile anesthetics. However, maintaining the balanced anesthesia in long-time surgery using TIVA is challenging and may sometime cause problems including body movement during microsurgery.

[Assessment of Motor and Language Function during Awake Surgery].

Awake surgery enables the evaluation of neurological functions that are difficult to assess with a conventional electrophysiological examination and is useful in the evaluation of language function. Awake surgery is a team effort involving anesthesiologists and rehabilitation physicians who evaluate motor and language functions, and information sharing during the perioperative period is important. Some points regarding surgical preparation and anesthesia methods are unique and must be well understood.

Visual networks: Electric brain stimulation and diffusion tensor imaging.

Objective: The present study investigated the networks of visual functional areas using electric brain stimulation (EBS) and diffusion tensor imaging (DTI).

Methods: Thirteen patients with intractable focal epilepsy in which visual functional areas were identified by EBS were enrolled. An electric stimulation at 50Hz was applied to electrodes during several tasks.

Computational Fluid Dynamics Analysis Features in Aneurysm Development in Rats.

The investigation of how to control the development and growth of cerebral aneurysms is important for the prevention of subarachnoid hemorrhage. Although there have been several types of research studies on computational fluid dynamics (CFD) analysis of brain aneurysm development and growth, there has been no unified interpretation of the CFD analysis results. The purpose of this study is to clarify the characteristics of CFD analysis results related to the development of cerebral aneurysms using an animal model.

Transcranial electrical stimulation technique for induction of unilateral motor evoked potentials.

Objective: Transcranial electrical stimulation motor evoked potentials (TES-MEP) are widely used to monitor motor function; however, broad current spread and induced body movement are limitations of this technique. We herein report a localized stimulation technique for TES-MEP that induces unilateral MEP responses.

Methods: The stimulation of C1(+)-C4(-) or C2(+)-C3(-) was performed to induce right- or left-sided muscle contraction, respectively, in 70 patients.

Microbleeds Due to Reperfusion Enhance Early Seizures after Carotid Ligation in a Rat Ischemic Model.

Impaired reperfusion in ischemic brain disease is a condition that we are increasingly confronted with owing to recent advances in reperfusion therapy. In the present study, rat models of reperfusion were investigated to determine the causes of acute seizures using magnetic resonance imaging (MRI) and histopathological specimens. Rat models of bilateral common carotid artery ligation followed by reperfusion and complete occlusion were created.

Prediction of Early Postoperative Language Function by Quantitative Evaluation with Visual and Auditory Naming Tasks during Awake Craniotomy for Brain Tumor Resection: Significance of Auditory Naming Task.

Language tasks for monitoring intraoperative language symptoms have not yet been established. This study aimed to examine whether the quantitative evaluation of language function with visual and auditory naming during awake craniotomy predicts early postoperative language function in patients. Thirty-seven patients with brain tumors in the language-dominant hemisphere were included.

Deep learning for the diagnosis of mesial temporal lobe epilepsy.

Objective: This study aimed to enable the automatic detection of the hippocampus and diagnose mesial temporal lobe epilepsy (MTLE) with the hippocampus as the epileptogenic area using artificial intelligence (AI). We compared the diagnostic accuracies of AI and neurosurgical physicians for MTLE with the hippocampus as the epileptogenic area.

Method: In this study, we used an AI program to diagnose MTLE.

Effect of remimazolam on intraoperative neurophysiology monitoring of visual-evoked potential: a case series.

There are very few reports on the effects of benzodiazepines such as midazolam and diazepam on intraoperative visual-evoked potential (VEP), and there is no report on the effect of remimazolam at all. Five patients underwent neurosurgery using VEP monitoring for avoiding surgical injury to the optic nerve. In all cases, drug administration was based on actual body weight.

Male sex and presence of preoperative symptoms are associated with early recurrence of WHO grade I meningiomas after surgical resection: analysis from the nationwide Brain Tumor Registry of Japan.

This study aimed to assess the risk factors for the recurrence of WHO grade I intracranial meningiomas using the Brain Tumor Registry of Japan (BTRJ) database. We extracted the data of 4641 patients with intracranial WHO grade I meningiomas treated only by surgical resection between 2001 and 2008. We conducted complete data analysis (n = 3690) and multiple imputation analysis (n = 4641) to adjust for missing data on tumor size.

Usefulness of Intraoperative Electrocorticography for the Localization of Epileptogenic Zones.

Intraoperative electrocorticography (iECoG) is widely performed to identify irritative zones in the cortex during brain surgery; however, several limitations (e.g., short recording times and the effects of general anesthesia) reduce its effectiveness.

The intraoperative motor-evoked potential when propofol was changed to remimazolam during general anesthesia: a case series.

Remimazolam is a short-acting benzodiazepine that was approved for clinical use in 2020. We report three patients who underwent surgery for cerebral and spinal cord tumors, in whom transcranial electrical stimulation-motor-evoked potential (TES-MEP) was successfully monitored under general anesthesia with remimazolam. During total intravenous anesthesia with propofol at a target concentration of 2.