The anterior sylvian point as a reliable landmark for the anterior temporal lobectomy in mesial temporal lobe epilepsy: technical note, case series, and cadaveric dissection.

Introduction: Mesial temporal lobe epilepsy (MTLE) is one of the most prevalent forms of focal epilepsy in surgical series, particularly among adults. Over the decades, different surgical strategies have been developed to address drug-resistant epilepsy while safeguarding neurological and cognitive functions. Among these strategies, anterior temporal lobectomy (ATL), involving the removal of the temporal pole and mesial temporal structures, has emerged as a widely employed technique. Numerous modifications have been proposed to mitigate the risks associated with aphasia, cognitive issues, and visual field defects. Methods: Our approach is elucidated through intraoperative and cadaveric dissections, complemented by neuroradiological and cadaveric measurements of key anatomical landmarks. A retrospective analysis of patients with drug-resistant MTLE who were treated using our ATL technique at IRCCS Neuromed (Pozzilli) is presented. Results: A total of 385 patients were treated with our ATL subpial technique anatomically focused on the anterior Sylvian point (ASyP). The mean FU was 9.9 ± 5.4 years (range 1-24). In total, 84%of patients were free of seizures during the last follow-up, with no permanent neurological deficits. Transient defects were as follows: aphasia in 3% of patients, visual field defects in 2% of patients, hemiparesis in 2% of patients, and cognitive/memory impairments in 0.8% of patients. In cadaveric dissections, the ASyP was found at a mean distance from the temporal pole of 3.4 ± 0.2 cm (range 3-3.8) at the right side and 3.5 ± 0.2 cm (3.2-3.9) at the left side. In neuroimaging, the ASyP resulted anterior to the temporal horn tip in all cases at a mean distance of 3.2 ± 0.3 mm (range 2.7-3.6) at the right side and 3.5 ± 0.4 mm (range 2.8-3.8) at the left side. Discussion: To the best of our knowledge, this study first introduces the ASyP as a reliable and reproducible cortical landmark to perform the ATL to overcome the patients' variabilities, the risk of Meyer's loop injury, and the bias of intraoperative measurements. Our findings demonstrate that ASyP can be a safe cortical landmark that is useful in MTLE surgery because it is constantly present and is anterior to risky temporal regions such as temporal horn and language networks.

Parasagittal Meningiomas: The Impact of Sinus Opening and Grade of Resection on Clinical Outcome and Recurrence in a Consecutive Series of Patients.

BACKGROUND: Surgical management of parasagittal meningiomas (PMs) remains controversial in the literature. The need to pursue a resection as radical as possible and the high risk of venous injuries contribute to making the sinus opening a widely argued choice. This study aimed to analyze factors affecting the risk of recurrence and to assess clinical outcomes of patients who underwent surgical resection of PMs with conservative or aggressive management of the intrasinusal portion. METHODS: A single-institution retrospective review of all patients with PM surgically treated between January 2013 and March 2021 was conducted. RESULTS: Among 56 patients, the sinus was opened in 32 patients (57%), and a conservative approach was used in 24 patients (43%). The sinus opening was found to be a predictive factor of radical resection (Simpson grade [SG] I-II) (P = 0.007). SG was the only predictive factor of recurrence (P < 0.001). The radical resection group (SG I-II) showed recurrence-free survival at 72 months of about 90% versus 30% in the non-radical resection group (SG III-IV) (log-rank test = 14.21, P < 0.001). Aggressive management of the sinus and radical resection were not found to be related to permanent deficit (P = 0.214 and P = 0.254) or worsening of Karnofsky performance scale score (P = 0.822 and P = 0.933). CONCLUSIONS: Removal of the intrasinusal portion of the tumor using standard procedures is not associated with a higher risk of permanent deficit or worsening of Karnofsky performance scale and reduces the risk of recurrence.

Key role of microsurgical dissections on cadaveric specimens in neurosurgical training: Setting up a new research anatomical laboratory and defining neuroanatomical milestones.

Introduction: Neurosurgery is one of the most complex surgical disciplines where psychomotor skills and deep anatomical and neurological knowledge find their maximum expression. A long period of preparation is necessary to acquire a solid theoretical background and technical skills, improve manual dexterity and visuospatial ability, and try and refine surgical techniques. Moreover, both studying and surgical practice are necessary to deeply understand neuroanatomy, the relationships between structures, and the three-dimensional (3D) orientation that is the core of neurosurgeons' preparation. For all these reasons, a microsurgical neuroanatomy laboratory with human cadaveric specimens results in a unique and irreplaceable training tool that allows the reproduction of patients' positions, 3D anatomy, tissues' consistencies, and step-by-step surgical procedures almost identical to the real ones. Methods: We describe our experience in setting up a new microsurgical neuroanatomy lab (IRCCS Neuromed, Pozzilli, Italy), focusing on the development of training activity programs and microsurgical milestones useful to train the next generation of surgeons. All the required materials and instruments were listed. Results: Six competency levels were designed according to the year of residency, with training exercises and procedures defined for each competency level: (1) soft tissue dissections, bone drilling, and microsurgical suturing; (2) basic craniotomies and neurovascular anatomy; (3) white matter dissection; (4) skull base transcranial approaches; (5) endoscopic approaches; and (6) microanastomosis. A checklist with the milestones was provided. Discussion: Microsurgical dissection of human cadaveric specimens is the optimal way to learn and train on neuroanatomy and neurosurgical procedures before performing them safely in the operating room. We provided a "neurosurgery booklet" with progressive milestones for neurosurgical residents. This step-by-step program may improve the quality of training and guarantee equal skill acquisition across countries. We believe that more efforts should be made to create new microsurgical laboratories, popularize the importance of body donation, and establish a network between universities and laboratories to introduce a compulsory operative training program.

Cisternostomy for malignant middle cerebral artery infarction: proposed pathophysiological mechanisms and preliminary results.

BACKGROUND: The ischaemic stroke of the territory of the middle cerebral artery represents an event burdened by high mortality and severe morbidity. The proposed medical treatments do not always prove effective. Decompressive craniectomy allows the ischaemic tissue to shift through the surgical defect rather than to the unaffected regions of the brain, thus avoiding secondary damage due to increased intracranial pressure. In this study, we propose a novel treatment for these patients characterised by surgical fenestration of the cisterns of the skull base. METHODS: We have treated 16 patients affected by malignant middle cerebral artery ischaemia and treated with cisternostomy between August 2018 and December 2019. The clinical history, neurological examination findings and neuroradiological studies (brain CT, CT angiography, MRI) were performed to diagnose stroke. Clinical examination was recorded on admission and preoperatively using the Glasgow Coma Scale and the National Institutes of Health Stroke Scale. RESULTS: The study included 16 patients, 10 males and 6 females. The mean age at surgery was 60.1 years (range 19-73). Surgical procedure was performed in all patients. The patients underwent immediate postoperative CT scan and were in the early hours evaluated in sedation window. In total, we recorded two deaths (12.5%). A functional outcome between mRS 0-3, defined as favourable, was observed in 9 (64.2%) patients 9 months after discharge. A functional outcome between mRS 4-6, defined as poor, was observed in 5 (35.7%) patients 9 months after discharge. CONCLUSIONS: The obtained clinical results appear, however, substantially overlapping to decompressive craniectomy. Cisternostomy results in a favourable functional outcome after 9 months. This proposed technique permits that the patient no longer should be undergone cranioplasty thus avoiding the possible complications related to this procedure. The results are certainly interesting but higher case numbers are needed to reach definitive conclusions.

Hidden intra-meatal CSF fistula related to VP shunt as a cause for fatal tension pneumocephalus after vestibular schwannoma resection.

BACKGROUND: Cerebrospinal fluid (CSF) leak through petrosal air cells is a known complication after drilling the posterior wall of the internal acoustic canal (IAC) for resection of vestibular schwannoma (VS). Whereas mild pneumocephalus is common after retrosigmoid craniotomy, tension pneumocephalus has been rarely documented. OBJECTIVE: To testify a case of fatal tension pneumocephalus after VS resection in a patient with ventriculo-peritoneal (VP) shunt and to propose possible recommendations to limit the risk of this dramatic complication. METHODS: A case of fatal tension pneumocephalus after VS resection in presence of hidden CSF fistula is illustrated with pre- and post-operative images. RESULTS: In the uneventful situation of concomitant post-operative CSF fistula in presence of VP shunt, tension pneumocephalus may occur. The negative pressure created by the shunt system and the presence of osteo-dural defect allow the air to enter and, at the same time, prevent the outflow. CONCLUSION: After VS resection, tension pneumocephalus can occur as a consequence of CSF fistula from petrosal air cells in the presence of functioning VP shunt. Precautions as pre-operative increase to 'virtual-off' the pressure of the valve, subsequences CT scans after surgery and sealing of the petrous air cells are recommended to avoid such as fatal complication.

Multilevel Postoperative Cervical Epidural Hematoma: Complete Removal Through Catheter Drainage of the Unexposed Blood Collection.

BACKGROUND: Postoperative spinal epidural hematoma is a rare complication of anterior cervical discectomy and fusion. This condition may rapidly produce severe neurologic deficits, often requiring a prompt surgical decompression. A multilevel extension of the epidural bleeding has been rarely described after anterior cervical procedures. In such cases, the choice of the most suitable surgical approach may be challenging. Herein, we describe an effective surgical decompression of a C2-T1 ventral epidural hematoma following anterior cervical discectomy and fusion at the C5-C6 level. METHODS: By reopening the previous approach, the C5-C6 intersomatic cage was removed and the surgical field inspected for bleeding. After removal of the spinal epidural hematoma at this level, a lumbar external drainage catheter was inserted into the epidural space to perform multiple irrigations with saline solution until the washing fluid was clear. RESULTS: Immediate postoperative cervical computed tomography and magnetic resonance imaging revealed gross total removal of the epidural hematoma and complete decompression of the spinal cord all along the affected tract. Early postoperative neurologic examination revealed mild lower extremity weakness that fully recovered within hours. CONCLUSIONS: Although rare, multilevel epidural hematoma following anterior cervical decompression represents a serious complication. The revision of the previous anterior cervical approach may be considered the first treatment option, allowing to control the primary bleeding site. Catheter irrigation of the epidural space with saline solution may be a useful technique for removal of unexposed residual blood collection, avoiding the need for posterior laminectomy or other unnecessary bone demolition.

An Unusual But Possible Complication After Endoscopic Third Ventriculostomy.

BACKGROUND: We present an unusual but possible complication after ETV for the treatment of acute hydrocephalus due to malfunction of a previously implanted V-P shunt. CASE DESCRIPTION: A 12-year-old male patient was urgently operated upon by means of an endoscopic third-ventriculostomy and the positioning of a temporary external ventricular catheter because of the malfunction of a previously implanted V-P shunt; immediately after the operation, the tip of the external catheter caused an obstruction of the ostomy, which was resolved with the withdrawn of catheter for circa 1 cm, left closed and ultimately removed after 4 days. The patient did not present any further symptom and remained shunt-free at the last 2-year follow-up visit. CONCLUSIONS: One should consider such occurrence in cases of early ETV failure when a ventricular catheter is left in situ, even though temporarily.

A Novel Technical Refinement of Microvascular Decompression: Pain Relief and Complication Rate in a Consecutive Series of Patients With Trigeminal Neuralgia.

BACKGROUND: Microvascular decompression (MVD) represents a milestone for the treatment of trigeminal neuralgia (TN). Nevertheless, several complications still occur and may negatively affect the outcome. We recently proposed some technical nuances for complication avoidance related to MVD. OBJECTIVE: To verify the efficacy of the proposed refinement of the standard MVD technique in terms of resolution of the pain and reduction of complication rates. METHODS: We analyzed surgical and outcome data of patients with TN using a novel surgical refinement to MVD, over the last 4 yr. Outcome variables included pain relief, facial numbness, muscular atrophy, local cutaneous occipital and temporal pain or numbness, cerebellar injury, hearing loss, cranial nerve deficits, wound infection, and cerebrospinal fluid (CSF) leak. Overall complication rate was defined as the occurrence of any of the aforementioned items. RESULTS: A total of 72 consecutive patients were enrolled in the study. Pain relief was achieved in 91.6% and 88.8% of patients at 1- and 4-yr follow-up, respectively. No patient reported postoperative facial numbness during the entire follow-up period. The incidence of CSF leak was 1.4%. One patient developed a complete hearing loss and another a minor cerebellar ischemia. There was no mortality. The overall complication rate was 5.6%, but only 1.4% of patients experienced permanent sequelae. CONCLUSION: The proposed refinement of the standard MVD technique has proved effective in maintaining excellent results in terms of pain relief while minimizing the overall complication rate associated with this surgical approach.

The Value of Preoperative Planning Based on Navigated Transcranical Magnetic Stimulation for Surgical Treatment of Brain Metastases Located in the Perisylvian Area.

BACKGROUND: Brain metastases are the most common neoplasms in adults. When brain metastases are located in eloquent areas, their treatment still seems controversial and not clearly defined. It is therefore essential to provide correct preoperative planning to better define extension and characterization of brain metastasis. METHODS: We retrospectively looked for the tumor database of our institution, patients with single brain metastasis, located in the sylvian area, who underwent resection with the support of intraoperative neurophysiologic monitoring between 2008 and 2018. RESULTS: We retrieved data for 30 adults, each with a single brain metastasis that was located in the sylvian area, including the insula and the lower portion of the motor cortex. Neuronavigation and the intraoperative visualization of the navigated transcranial magnetic stimulation-based reconstruction of functional networks were used to delineate the ideal trajectory toward the lesion. The Karnofsky Performance Status significantly improved in the postoperative period. CONCLUSIONS: The correct planning of brain metastasis allows more secure removal of the neoplastic lesion, avoiding and/or reducing the appearance of neurologic deficits. Navigated transcranial magnetic stimulation represents a new method that can promote a more complete and safer resection of the metastatic lesion in eloquent areas. An optimal surgical result, in the absence of postoperative neurologic deficits, allows the patient to undertake adjuvant therapy able to prolong survival.

Open Kyphoplasty for Metastatic Spine Disease: A Retrospective Clinical Series.

OBJECTIVE: Symptomatic metastatic spine disease (MSD), is a challenging disease involving 3%-20% of patients with bone metastases. Different surgical options are available and must be tailored to the general and neurologic conditions of the patients. Open kyphoplasty (OKP) refers to decompressive hemilaminectomy, associated with a contralateral percutaneous kyphoplasty, and in some cases, to a posterior stabilization. The aim of the study was to critically review our experience during the last decade with OKP in patients with cancer. METHODS: Fifty-three patients with cancer underwent OKP for symptomatic MSD. The Tokuhashi score and Spinal Instability Neoplastic Score were calculated for each patient. Length of hospital stay, perioperative complications, incidence of adjacent-level fractures, and median survival after surgery were evaluated. Karnofsky Performance Status, visual analog scale, and Dennis Pain Score were calculated preoperatively, postoperatively, and at last follow-up. RESULTS: Median Tokuhashi score and Spinal Instability Neoplastic Score were 10 and 10, respectively. The mean volume of filling material inserted was 3.6 mL. Median operative time was 180 minutes. Complications included 8 leakages (15%), 2 permanent motor deficits (3.8%), and 2 asymptomatic pulmonary embolisms (3.8%). Mean length of hospital stay was 7 days. A significant improvement was observed in Karnofsky Performance Status, visual analog scale score, and Dennis Pain Score (P < 0.0001). Median follow-up was 16 months and overall survival 22 months. CONCLUSIONS: OKP was an effective treatment of symptomatic MSDs in selected oncologic patients with low Tokuhashi scores. It relieved lateral epidural compressions, expanded indications of palliative surgery in patients who were not otherwise surgical candidates, and rapidly dealt with cement leakages.

Endoscopic Endonasal Odontoidectomy and Posterior Fusion in a Single-Stage Surgery: Description of Surgical Technique and Outcome.

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The role of surgical resection in patients with brain metastases.

PURPOSE OF REVIEW: Treatment of brain metastases represent a critical issue and different options have to be considered according to patients and tumour characteristics; in recent years, new therapeutic strategies have been proposed. In this review, we discuss the role of surgical resection on the basis of patient selection, new surgical techniques and the use of intraoperative adjuncts. The integration with postoperative whole brain radiotherapy will be also outlined because alternative treatment options are currently available. RECENT FINDINGS: Surgical removal has been considered the mainstay in the treatment of brain metastases, in selected patients, with limited number of intracranial lesions and controlled primary disease, mainly in combination with whole brain radiotherapy. In the last few years, the increasing role of stereotactic focal radiotherapy has deeply modified the indications to open surgical procedures and whole brain radiotherapy. SUMMARY: The appearance of brain metastases is considered a sign of bad prognosis. Treatment of these lesions is important for quality of life, providing local tumour control, preventing death from neurological causes and improving survival, although potentially only in a minority of patients. Careful patient selection, with adequate evaluation of clinical prognostic score, the use of appropriate surgical techniques and surgical adjuncts are major determinants of favourable outcome in patients undergoing resection of brain metastases.