The "state of the art" of intraoperative neurophysiological monitoring: An Italian neurosurgical survey.

Introduction: Intraoperative Neurophysiological Monitoring (IOM) is widely used in neurosurgery but specific guidelines are lacking. Therefore, we can assume differences in IOM application between Neurosurgical centers. Research question: The section of Functional Neurosurgery of the Italian Society of Neurosurgery realized a survey aiming to obtain general data on the current practice of IOM in Italy. Materials and methods: A 22-item questionnaire was designed focusing on: volume procedures, indications, awake surgery, experience, organization and equipe. The questionnaire has been sent to Italian Neurosurgery centers. Results: A total of 54 centers completed the survey. The annual volume of surgeries range from 300 to 2000, and IOM is used in 10-20% of the procedures. In 46% of the cases is a neurologist or a neurophysiologist who performs IOM. For supra-tentorial pathology, almost all perform MEPs (94%) SSEPs (89%), direct cortical stimulation (85%). All centers perform IOM in spinal surgery and 95% in posterior fossa surgery. Among the 50% that perform peripheral nerve surgery, all use IOM. Awake surgery is performed by 70% of centers. The neurosurgeon is the only responsible for IOM in 35% of centers. In 83% of cases IOM implementation is adequate to the request. Discussion and conclusions: The Italian Neurosurgical centers perform IOM with high level of specialization, but differences exist in organization, techniques, and expertise. Our survey provides a snapshot of the state of the art in Italy and it could be a starting point to implement a consensus on the practice of IOM.

Intraoperative Neurophysiological Monitoring in Neurosurgery.

Intraoperative neurophysiological monitoring (IONM) is a crucial advancement in neurosurgery, enhancing procedural safety and precision. This technique involves continuous real-time assessment of neurophysiological signals, aiding surgeons in timely interventions to protect neural structures. In addition to inherent limitations, IONM necessitates a detailed anesthetic plan for accurate signal recording. Given the growing importance of IONM in neurosurgery, we conducted a narrative review including the most relevant studies about the modalities and their application in different fields of neurosurgery. In particular, this review provides insights for all physicians and healthcare professionals unfamiliar with IONM, elucidating commonly used techniques in neurosurgery. In particular, it discusses the roles of IONM in various neurosurgical settings such as tumoral brain resection, neurovascular surgery, epilepsy surgery, spinal surgery, and peripheral nerve surgery. Furthermore, it offers an overview of the anesthesiologic strategies and limitations of techniques essential for the effective implementation of IONM.

Eagle syndrome: An updated review.

Background: This work aims to review the current literature and our experience on vascular Eagle syndrome (ES) that can present misleading clinical presentations and better understand the possible therapeutic strategies. Methods: We reviewed the existing literature on PubMed from January 1, 2017, to December 31, 2022, including the sequential keywords "vascular AND Eagle syndrome," "vascular AND styloid syndrome," "vascular AND elongated styloid process," "vascular AND stylocarotid syndrome," and "Eagle syndrome AND carotid artery dissection." Results: 38 vascular ES cases, including our experience, were analyzed. The most frequent clinical onset was hemiparesis (n 21, 57%), but other regular clinical presentations were aphasia, loss of consciousness, amaurosis, headache, or a combination of the latter. Massive oral bleeding was reported only once in the literature before our case. Twelve patients were treated with only antiplatelet therapy, either single or double. Nine patients were treated with anticoagulation therapy only. In 14 patients, a carotid artery stent was used, associated with anticoagulation or antiplatelet therapy. In 17 cases, a styloid process (SP) resection was performed. Conclusion: ES has many clinical presentations, and carotid artery dissection resulting in oral bleeding seems rare. Literature results and our experience make us believe that when dealing with vascular ES, the best treatment strategy is endovascular internal carotid artery stenting with antiplatelet therapy, followed by surgical removal of the elongated SP to prevent stent fracture.

Deep brain stimulation of the dentato-rubro-thalamic tract in a case of Holmes tremor: a constrained spherical deconvolution (CSD)-guided procedure.

Deep brain stimulation (DBS) is an established treatment for movement disorders, including Holmes tremor (HT). HT is a rest and action tremor that occurs as a late symptom of brainstem lesions such as stroke. Unfortunately, it is frequently refractory to medical treatment, hence DBS surgery may be a good option. Due to variable results, the ideal target for DBS in HT still remains to be established, ranging from the thalamus to the globus pallidus internus, to the subthalamic nucleus. Pre-operative imaging also is very challenging, as the complexity of brain fiber architecture may prevent the correct positioning of the directional lead. Herein, we describe the case of a patient affected by a rubral tremor secondary to a brain hemorrhage, who had advanced pre-operative neuroimaging with constrained spherical deconvolution (CSD)-based tractography obtained from diffusion-weighted imaging (DWI) to identify the dentato-rubro-thalamic tract, involved in the pathophysiology of HT. The patient was then addressed to an awake DBS surgery, and with the help of intraoperative microelectrode recordings, a tailored DRTT-targeted procedure was performed. The stimulation determined an almost complete tremor suppression, with no significant side effects at a follow-up of 6 months, paving the way towards new effective techniques for the planning, i.e., CSD-based tractography and the treatment of refractory tremors.

Modified percutaneous biopsy of the spine: improvement of the technique.

PURPOSE: Biopsy of the spine can be performed by open surgery or percutaneous needle sampling. The first has the highest diagnostic yield while the second is a less invasive procedure with lower rate of complications and shorter hospitalization time. We described a modified technique of percutaneous biopsy using semi-rigid grasping forceps that may offer the advantages of both, open and minimally invasive surgery. METHODS: Thirty consecutive patients with spinal lesions requiring biopsy were admitted to Neurosurgical Unit of Belcolle Hospital (Viterbo, Italy) from January 2017 to September 2021. There was a suspicion of spondylodiscitis in 25 cases and of tumor in 5 cases. Percutanous trans-pedicular spine biopsy has been performed using this new semi-rigid grasping forceps. Combining the opening width, jaw length and full 360° rotation, the device allows a wide and precise sampling. RESULTS: Sampling was sufficient in all cases (100%); tumors was observed in 5 cases (16.7%%) with a percentage of definitive histopathologic diagnosis of 100% (n = 5); among the remaining patients histological examination yielded a diagnosis of spinal infection in 25 cases (100%), and microbiologic culture provided an aetiologic diagnosis in 23 cases (92%). All procedures were well tolerated, and no postoperative complications were observed. Levels involved included: thoracic (T5-T9) in 8 cases, thoracolumbar junction (T10-L2) in 12 cases and lumbar (L3-L5) in 10 cases. CONCLUSIONS: Percutaneous biopsy with the semi-rigid grasping forceps is a safe and effective procedure that can be used for diagnosis of both infectious and tumor lesions of the spine. It allows to obtain a larger specimen volume and to use a multidirectional trajectory for sampling, resulting in a minimally invasive technique with strong ability to yield etiologic diagnosis.

Delayed Intracerebral Hemorrhage After Pseudoaneurysm of Middle Meningeal Artery Rupture: Case Report, Literature Review, and Forensic Issues.

BACKGROUND: Traumatic pseudoaneurysm of the middle meningeal artery (PMMA) is rare. Its rupture is associated with high mortality, so an early diagnosis is recommended for this risky condition. In the absence of a specific guideline, computed tomography (CT), digital subtraction angiography, and CT angiography (CTA) are proposed for its diagnosis. CTA is the technique of choice even if it is almost never performed, especially in mild head injury. We report a rare case of a delayed rupture of PMMA, analyzed from a forensic point of view. METHODS: Fifteen days after mild blunt head trauma, characterized by temporal fracture and a small hemorrhage near the rim, a wide intraparenchymal hemorrhage (IPH) occurred. The onset of IPH was marked by neurologic deterioration and arm paralysis. Immediate head CT showed IPH, and CTA showed PMMA. Prompt surgery could not help patient survival. The goal of autopsy was to formulate the cause of death and to individuate potential medical negligence. RESULTS: In the literature, 16 cases of 54 are related to PMMA (26%) and are associated with IPH. IPH can be acute or delayed. Eight cases of acute IPH and 8 cases of delayed IPH (including our case), both coexisting with PMMA, are described. The literature review showed that the association of temporal rim fracture and a small hemorrhage nearby is highly predictive of PMMA formation. CONCLUSIONS: Therefore, in the presence of these 2 risk factors after heat trauma, CTA is strongly suggested.

Effects of somatostatin and its analogues on progenitor mesenchymal cells isolated from human pituitary adenomas.

PURPOSE: Progenitor mesenchymal cells (PMCs) have been found also in epithelial tumors and may derive from cancer stem cells (CSCs) by EMT mechanism. In this scenario, the effects of traditionally drugs on PMCs become of primary concern for therapeutic approaches. Previously, we isolated PMCs from acromegalic (GHomas) and not-functioning pituitary adenomas (NFPAs). Here we evaluate: (1) the role of EMT on their origin; (2) the presence of the somatostatin receptors (SSTR1-5); (3) the effects of somatostatin (SST) and its analogues (SSAs) on PMCs proliferation, apoptosis and SSTR1-5 expression. METHODS: PMCs were isolated from GHomas and NFPAs; the expression of E-CADHERIN and TGFßRII (referred to EMT), the expression of the SSTR1-5 as well as the proliferation and apoptosis were tested before and after drugs administration. RESULTS: Results show a decrease of E-CADHERIN and an increase of TGFßRII, confirming an EMT involvement; SSTR1-5 are more expressed by PMCs from GHomas than from NFPAs. SST and SSAs administration does not affect cell proliferation and SSTR1-5 expression on PMCs from NFPAs while in PMCs from GHomas, cell proliferation showed a marked decrease and a corresponding increase in the expression of SSTR1-2. Apoptosis rate and EMT were not affected by drugs administration. CONCLUSIONS: Results indicate as EMT may be related to the presence of PMCs on pituitary tumors; SSAs, currently used in the management of human GHomas, exert anti-proliferative effect also in PMCs that, because of their derivation from CSCs, may be a new meaningful target for drugs treatment.

Vagus nerve stimulation: clinical experience in drug-resistant pediatric epileptic patients.

INTRODUCTION: Vagus nerve stimulation (VNS) is an effective alternative treatment for patients with partial refractory epilepsy. Nevertheless, information regarding VNS in children is still limited. MATERIALS AND METHODS: The clinical efficacy, safety and neuropsychological effects of VNS in 34 children (mean age 11.5 years) with drug-resistant epilepsy were studied. Mean follow-up was 30.8 months. Nine patients have been diagnosed with Lennox-Gastaut Syndrome, nine patients were affected by severe partial epilepsy with bisynchronous EEG and drop attacks, and 16 patients suffered from partial epilepsy without bisynchronous EEG and fall seizures. Forms were designed for prospective data collection on each patient's history, seizures, implants, device settings, quality of life (QOL), neuropsychological assessment and adverse events. Surgical technique was performed both by standard two incisions and single neck incision. RESULTS: Mean reduction in total seizures was 39% at 3 months, 38% at 6 months, 49% at 12 months, 61% at 24 months and 71% at 36 months. Significant better results were obtained in partial epilepsy, with and without drop attacks, than in Lennox-Gastaut syndrome--three patients being seizure-free. No operative morbidity was reported. Side-effects were minor and transient--the most common were voice alteration and coughing during stimulation. In two patients, electrode breakage occurred 3 years after surgical procedure; in both cases, a new device was implanted after removing the vagal electrode coils and generator. CONCLUSION: VNS can be considered an appropriate strategy as an add-on treatment in children affected by drug-resistant partial epilepsy and ineligible for resective epilepsy surgery.