Functional cortical mapping and structural subcortical anatomy predicts intra-operative speech arrest: a nTMS-tractography study.

Objective: Cortical speech mapping using navigated Transcranial Magnetic Stimulation (nTMS) has a variable positive predictive value (PPV) when compared with intraoperative direct electrical stimulation.

Methods: This is a single centre prospective study of all patients undergoing pre-operative nTMS and tractography (frontal aslant tract (FAT) and arcuate fasciculus (AF)) for awake surgery between October 2018 and November 2023. We reviewed operative notes for speech arrest, collected data on demographics, histopathology and pre-/post-operative language assessment.

Anatomo-functional approach to multimodal motor mapping in diffuse glioma surgery: hierarchical networks.

Onco-functional balance during motor-eloquent diffuse glioma resection is challenging. This balance is personal according to individual background, treatment expectations and surgical experience. Nevertheless, preservation of muscle contraction in isolation is no longer an accepted outcome.

Microvascular Cortical Dynamics in Minimal Invasive Deep-Seated Brain Tumour Surgery.

Background: The tubular retractor-assisted minimally invasive parafascicular approach (trMIPS) is a transsulcal approach to deep-seated brain tumours. It is a safe surgical approach but its impact on the microvascular dynamics of the retracted cortex and its clinical implications are unknown.

Methods: This was a single-centre prospective study including patients with deep-seated brain tumours operated on with a trMIPS (BrainPath Nico System).

nTMS in spinal cord injury: Current evidence, challenges and a future direction.

Spinal Cord Injury (SCI) has devastating consequences for patients and their families. Over the last few decades, a renewed interest in the utilization of non-invasive and cost-effective therapeutic technologies in the management of patients with SCI has emerged. This includes stimulation with navigated transcranial magnetic stimulation (nTMS) in order to improve the outcome for these patients alongside with existing clinical tools.

Brain tumor patient perceptions toward repetitive transcranial magnetic stimulation for rehabilitation after surgery.

Background: Repetitive transcranial magnetic stimulation (rTMS) is established for depression and rehabilitation after stroke and is emerging for cognitive rehabilitation. We sought to evaluate patient and carer perceptions toward rTMS for rehabilitation after neurosurgery.

Methods: Two surveys were undertaken.

Preoperative and intraoperative neuromonitoring and mapping techniques impact oncological and functional outcomes in supratentorial function-eloquent brain tumours: a systematic review and meta-analysis.

Background: Supratentorial function-eloquent brain tumour surgeries challenge the balance between maximal tumour resection and preservation of neurological function. This study aims to evaluate the efficacy of preoperative and intraoperative mapping techniques on resection outcomes and post-operative deficits.

Methods: This systematic review and meta-analysis examined literature up to March 2023, sourced from PubMed, Embase, and Medline.

Improving postsurgical paresis in brain tumor patients by transcranial magnetic stimulation.

Background And Objectives: Recently, reduction of transcallosal inhibition by contralateral navigated repetitive transcranial magnetic stimulation (nrTMS) improved neurorehabilitation of glioma patients with new postoperative paresis. This multicentric study examines the effect of postoperative nrTMS in brain tumor patients to treat surgery-related upper extremity paresis.

Methods: This is a secondary analysis of two randomized and three one-arm studies in brain tumor patients with new/progressive postoperative paresis.

Diffusion changes in minimally invasive parafascicular approach for deep-seated tumours: impact on clinical outcomes.

Minimally invasive parafascicular surgery (MIPS) with the use of tubular retractors achieve a safe resection in deep seated tumours. Diffusion changes noted on postoperative imaging; the significance and clinical correlation of this remains poorly understood. Single centre retrospective cohort study of neuro-oncology patients undergoing MIPS.

In Situ Light-Source Delivery During 5-Aminulevulinic Acid-Guided High-Grade Glioma Resection: Spatial, Functional and Oncological Informed Surgery.

Background/objectives: 5-aminulevulinic acid (5-ALA)-guided surgery for high-grade gliomas remains a challenge in neuro-oncological surgery. Inconsistent fluorescence visualisation, subjective quantification and false negatives due to blood, haemostatic agents or optical impediments from the external light source are some of the limitations of the present technology.

Methods: The preliminary results from this single-centre retrospective study are presented from the first 35 patients operated upon with the novel Nico Myriad Spectra System©.

Transcranial Magnetic Stimulation-Electroencephalography (TMS-EEG) in Neurosurgery: Unexplored Path Towards Personalized Brain Surgery.

Transcranial Magnetic Stimulation-Electroencephalography (TMS-EEG) is a non-operative technique that allows for magnetic cortical stimulation (TMS) and analysis of the electrical currents generated in the brain (EEG). Despite the regular utilization of both techniques independently, little is known about the potential impact of their combination in neurosurgical practice. This scoping review, conducted following PRISMA guidelines, focused on TMS-EEG in epilepsy, neuro-oncology, and general neurosurgery.

Asymmetry of the Frontal Aslant Tract and Development of Supplementary Motor Area Syndrome.

The purpose of this study was to investigate preoperative interhemispheric differences of the FAT in relation to the onset of postoperative SMA syndrome. This was a single-center retrospective analysis of patients who underwent surgical resection of diffuse gliomas involving the SMA between 2018 and 2022. Inclusion criteria were availability of preoperative and postoperative Magnetic Resonance Imaging, no previous surgery, and no neurological deficits at presentation.

O-ARM navigation in tubular retractor-assisted minimal invasive parafascicular approach: technical note.

Trans-sulcal minimally invasive parafascicular surgery is an emerging technique to approach deep lesions with minimal brain retraction. Localization of the tubular retractor during surgery is critical, and intraoperative magnetic resonance imaging and neuronavigation present limitations. We describe the intraoperative use of O-Arm® coupled with pre-operative tractography to precisely localize the tubular retractor.

Bayesian networks for Risk Assessment and postoperative deficit prediction in intraoperative neurophysiology for brain surgery.

Purpose: To this day there is no consensus regarding evidence of usefulness of Intraoperative Neurophysiological Monitoring (IONM). Randomized controlled trials have not been performed in the past mainly because of difficulties in recruitment control subjects. In this study, we propose the use of Bayesian Networks to assess evidence in IONM.

Transcranial Magnetic Stimulation-Based Machine Learning Prediction of Tumor Grading in Motor-Eloquent Gliomas.

Background: Navigated transcranial magnetic stimulation (nTMS) is a well-established preoperative mapping tool for motor-eloquent glioma surgery. Machine learning (ML) and nTMS may improve clinical outcome prediction and histological correlation.

Methods: This was a retrospective cohort study of patients who underwent surgery for motor-eloquent gliomas between 2018 and 2022.

Advancing Intraoperative Neurophysiological Monitoring With Human Reflexes.

Human reflexes are simple motor responses that are automatically elicited by various sensory inputs. These reflexes can provide valuable insights into the functioning of the nervous system, particularly the brainstem and spinal cord. Reflexes involving the brainstem, such as the blink reflex, laryngeal adductor reflex, trigeminal hypoglossal reflex, and masseter H reflex, offer immediate information about the cranial-nerve functionality and the overall state of the brainstem.

In-House Intraoperative Monitoring in Neurosurgery in England - Benefits and Challenges.

Background: Intraoperative neurophysiological monitoring (IOM) is a valuable adjunct for neurosurgical operative techniques, and has been shown to improve clinical outcomes in cranial and spinal surgery. It is not necessarily provided by NHS hospitals so may be outsourced to private companies, which are expensive and at cost to the NHS trusts. We discuss the benefits and challenges of developing an in-house service.

Impact of Preoperative Mapping and Intraoperative Neuromonitoring in Minimally Invasive Parafascicular Surgery for Deep-Seated Lesions.

Background: Transsulcal tubular retractor-assisted minimally invasive parafascicular surgery changes the surgical strategy for deep-seated lesions by promoting a deficit-sparing approach. When integrated with preoperative brain mapping and intraoperative neuromonitoring (IONM), this approach may potentially improve patient outcomes. In this study, we assessed the impact of preoperative brain mapping and IONM in tubular retractor-assisted neuro-oncological surgery.

Cortical-Subcortical Functional Preservation and Rehabilitation in Neuro-Oncology: Proof-of-Concept Study.

Surgical management of deep-seated brain tumors requires precise functional navigation and minimally invasive surgery. Preoperative mapping using navigated transcranial magnetic stimulation (nTMS), intraoperative neurophysiological monitoring (IONM), and minimally invasive parafascicular surgery (MIPS) act together in a functional-sparing approach. nTMS also provides a rehabilitation tool to maximize functional recovery.

Intraoperative Neuromonitoring of the Visual Pathway in Asleep Neuro-Oncology Surgery.

Brain tumour surgery in visual eloquent areas poses significant challenges to neurosurgeons and has reported inconsistent results. This is a single-centre prospective cohort study of patients admitted for asleep surgery of intra-axial lesions in visual eloquent areas. Demographic and clinical information, data from tractography and visual evoked potentials (VEPs) monitoring were recorded and correlated with visual outcomes.

Intraoperative Neurophysiological Monitoring for Intradural Extramedullary Spinal Tumours.

Study Design: Retrospective cohort study.

Objectives: Intraoperative neurophysiological monitoring (IONM) is widely used in spinal neurosurgery, particularly for intramedullary tumours. However, its validity in intradural extramedullary (IDEM) spinal tumours is less clearly defined, this being the focus of this study.

Continuous Microdebrider-Based Dynamic Subcortical Motor Mapping: A Technical Advance in Tubular Retractor-Assisted Surgery.

Background: Transsulcal minimally invasive parafasicular (TsMIP) approaches to brain tumor resection use tubular retractors to minimize iatrogenic brain injury. Dynamic cortical and subcortical continuous neurophysiological mapping facilitates safer resection of motor-eloquent tumors.

Objective: To describe a new technique to address the challenge of combining TsMIP with tubular retractors and dynamic subcortical mapping using a single electrified stimulating microdebrider instrument.

Methodology for eliciting the brainstem trigeminal-hypoglossal reflex in humans under general anesthesia.

Objective: Brainstem trigeminal-hypoglossal reflexes (THRs), also known as the jaw-tongue reflexes, coordinate the position of the tongue in the mouth in relation to the jaw movement during oromotor behaviors such as mastication, swallowing, vocalization, and breathing. Their use in brainstem surgery however, has never been assessed in spite of its potential benefit possibly due to the lack of a methodology to elicit these reflexes under general anesthesia.

Methods: We proposed a technique to elicit the THRs during total intravenous anesthesia (TIVA) consisting on a V3 infrazygomatic train stimulation paradigm and recording from the Styloglossus (31 patients) and the Genioglossus (21 patients) muscles to elicit long latency responses.