Bone graft absorption complication following cranioplasty: A retrospective institutional study.

The aim of the present retrospective study was to confer the factors that are related to bone graft absorption and affect the outcomes of patients following cranioplasty (CPL). The present retrospective study includes cases of patients that underwent CPL between February, 2013 and December, 2022. All participants had a follow-up period of 1 to 10 years from the day of discharge from the hospital. In total, 116 (62.3%) of the 186 patients that underwent decompressive craniectomy (DC) were enrolled in the present study for CPL. A total of 109 (93.9%) patients were included in group A, and 7 (6.0%) patients were included in group B. On the whole, the results of the present study suggest that a CPL after 2.5-7.7 months of DC increases the possibility of bone absorption.

Management of intracranial cavernous malformations using conservative vs. surgical and/or radiosurgical treatment: A systematic review and meta­analysis.

Intracranial cavernous malformations (CMs) are vascular lesions with a high bleeding rate. At present, the debate regarding their treatment is still ongoing. The present systematic review and meta-analysis aimed to evaluate the safety of surgery or radiosurgery (SRS) for the management of CMs and to determine their potential outcomes compared with conservative treatment. The present systematic review and meta-analysis investigated the relative articles involving the management of intracranial CMs, namely their natural history (conservative treatment) vs. surgical/SRS treatment through electronic databases until June, 2023. The collected variables included the first author's name, the study period covered, the year of publication, the total number of patients examined and their age, and the number of males. In total, six articles met the eligibility criteria. The total number of patients was 399 (157 in the surgery/SRS group and 242 in the conservative treatment group). The results revealed that surgical or SRS management is a safe procedure for CMs compared with conservative treatment. Notably, the use of hemosiderin in the pre-MRI, the free of seizures parameter and the neurological deficit parameters were associated with improved outcomes in the surgical or SRS group of patients.

Current state of the art of traditional and minimal invasive epilepsy surgery approaches.

Introduction: Open resective surgery remains the main treatment modality for refractory epilepsy, but is often considered a last resort option due to its invasiveness. Research question: This manuscript aims to provide an overview on traditional as well as minimally invasive surgical approaches in modern state of the art epilepsy surgery. Materials and methods: This narrative review addresses both historical and contemporary as well as minimal invasive surgical approaches in epilepsy surgery. Peer-reviewed published articles were retrieved from PubMed and Scopus. Only articles written in English were considered for this work. A range of traditional and minimally invasive surgical approaches in epilepsy surgery were examined, and their respective advantages and disadvantages have been summarized. Results: The following approaches and techniques are discussed: minimally invasive diagnostics in epilepsy surgery, anterior temporal lobectomy, functional temporal lobectomy, selective amygdalohippocampectomy through a transsylvian, transcortical, or subtemporal approach, insulo-opercular corticectomies compared to laser interstitial thermal therapy, radiofrequency thermocoagulation, stereotactic radiosurgery, neuromodulation, high intensity focused ultrasound, and disconnection surgery including callosotomy, hemispherotomy, and subpial transections. Discussion and conclusion: Understanding the benefits and disadvantages of different surgical approaches and strategies in traditional and minimal invasive epilepsy surgery might improve the surgical decision tree, as not all procedures are appropriate for all patients.

Functional hemispheric disconnection procedures for chronic epilepsy: history, indications, techniques, complications and current practice in Europe. A consensus statement on behalf of the EANS functional neurosurgery section.

Introduction: The surgical procedure for severe, drug-resistant, unilateral hemispheric epilepsy is challenging. Over the last decades the surgical landscape for hemispheric disconnection procedures changed from anatomical hemispherectomy to functional hemispherotomy with a reduction of complications and stable good seizure outcome. Here, a task force of European epilepsy surgeons prepared, on behalf of the EANS Section for Functional Neurosurgery, a consensus statement on different aspects of the hemispheric disconnection procedure. Research question: To determine history, indication, timing, techniques, complications and current practice in Europe for hemispheric disconnection procedures in drug-resistant epilepsy. Material and methods: Relevant literature on the topic was collected by a literature search based on the PRISMA 2020 guidelines. Results: A comprehensive overview on the historical development of hemispheric disconnection procedures for epilepsy is presented, while discussing indications, timing, surgical techniques and complications. Current practice for this procedure in European epilepsy surgery centers is provided. At present, our knowledge of long-term seizure outcomes primarily stems from open surgical disconnection procedures. Although minimal invasive surgical techniques in epilepsy are rapidly developing and reported in case reports or small case series, long-term seizure outcome remain uncertain and needs to be reported. Discussion and conclusion: This is the first paper presenting a European consensus statement regarding history, indications, techniques and complications of hemispheric disconnection procedures for different causes of chronic, drug-resistant epilepsy. Furthermore, it serves as the pioneering document to report a comprehensive overview of the current surgical practices regarding this type of surgery employed in renowned epilepsy surgery centers across Europe.

Neurosurgery Training in Greece.

OBJECTIVE: The structure and specifics of neurosurgery residency training vary substantially across programs and countries, potentially leading to differences in clinical reasoning, surgical skills, and professionalism. The Greek neurosurgical training system is unique in numerous respects. This manuscript delineates the current state of neurosurgical residency training in Greece and outlines future directions. METHODS: A narrative review was conducted to describe the Greek neurosurgical residency training structure. The perspectives of the authors regarding challenges in training and future directions were synthesized. RESULTS: This manuscript describes the neurosurgery residency curriculum and board certification process, existing training programs, and key challenges in neurosurgery residency training in Greece. The authors propose future directions to reform neurosurgical training in Greece. CONCLUSIONS: Neurosurgery residency training in Greece has been largely unchanged for many years. This review leads to suggested modification of the existing training process may improve the quality of training and equip neurosurgeons to respond to the rapidly changing landscape of the field.

Localization of Vestibular Cortex Using Electrical Cortical Stimulation: A Systematic Literature Review.

The vestibular system plays a fundamental role in body orientation, posture control, and spatial and body motion perception, as well as in gaze and eye movements. We aimed to review the current knowledge regarding the location of the cortical and subcortical areas, implicated in the processing of vestibular stimuli. The search was performed in PubMed and Scopus. We focused on studies reporting on vestibular manifestations after electrical cortical stimulation. A total of 16 studies were finally included. Two main types of vestibular responses were elicited, including vertigo and perception of body movement. The latter could be either rotatory or translational. Electrical stimulation of the temporal structures elicited mainly vertigo, while stimulation of the parietal lobe was associated with perceptions of body movement. Stimulation of the occipital lobe produced vertigo with visual manifestations. There was evidence that the vestibular responses became more robust with increasing current intensity. Low-frequency stimulation proved to be more effective than high-frequency in eliciting vestibular responses. Numerous non-vestibular responses were recorded after stimulation of the vestibular cortex, including somatosensory, viscero-sensory, and emotional manifestations. Newer imaging modalities such as functional MRI (fMRI), Positron Emission Tomography (PET), SPECT, and near infra-red spectroscopy (NIRS) can provide useful information regarding localization of the vestibular cortex.

Role of decompressive craniectomy in the management of acute ischemic stroke (Review).

The application of decompressive craniectomy (DC) is thoroughly documented in the management of brain edema, particularly following traumatic brain injury. However, an increasing amount of concern is developing among the universal medical community as regards the application of DC in the treatment of other causes of brain edema, such as subarachnoid hemorrhage, cerebral hemorrhage, sinus thrombosis and encephalitis. Managing stroke continues to remain challenging, and demands the aggressive and intensive consulting of a number of medical specialties. Middle cerebral artery (MCA) infarcts, which consist of 1-10% of all supratentorial infarcts, are often associated with mass effects, and high mortality and morbidity rates. Over the past three decades, a number of neurosurgical medical centers have reported their experience with the application of DC in the treatment of malignant MCA infarction with varying results. In addition, over the past decade, major efforts have been dedicated to multicenter randomized clinical trials. The present study reviews the pertinent literature to outline the use of DC in the management of malignant MCA infarction. The PubMed database was systematically searched for the following terms: 'Malignant cerebral infarction', 'surgery for stroke', 'DC for cerebral infarction', and all their combinations. Case reports were excluded from the review. The articles were categorized into a number of groups; the majority of these were human clinical studies, with a few animal experimental clinical studies. The surgical technique involved was DC, or hemicraniectomy. Other aspects that were included in the selection of articles were methodological characteristics and the number of patients. The multicenter randomized trials were promising. The mortality rate has unanimously decreased. As for the functional outcome, different scales were employed; the Glasgow Outcome Scale Extended was not sufficient; the Modified Rankin Scale and Bathel index, as well as other scales, were applied. Other aspects considered were demographics, statistics and the very interesting radiological ones. There is no doubt that DC decreases mortality rates, as shown in all clinical trials. Functional outcome appears to be the goal standard in modern-era neurosurgery, and quality of life should be further discussed among the medical community and with patient consent.

Surgical outcomes of patients with unruptured anterior vs. inferior circulation aneurysms: A meta­analysis.

The treatment option for unruptured intracranial aneurysms (UIAs) depends on their natural history-related risk of rupture vs. the risk of surgical management. The present meta-analysis sought to assess the association between the surgical outcomes of anterior and posterior circulation UIAs. The present study investigated the comparative articles involving the surgical treatment of anterior vs. posterior circulation UIAs through electronic databases, including the Cochrane Library, PubMed (1980 to March, 2023), Medline (1980 to March, 2023) and EMBASE (1980 to March, 2023). Quoting all exclusion and inclusion criteria, nine articles finally remained for statistical analysis. The entire number of patients included in these nine articles was 3,253 (2,662 in the anterior and 591 in the posterior circulation UIAs group). The present meta-analysis proposes that the surgical treatment of anterior circulation UIAs is associated with better outcomes compared with the surgical management of posterior circulation UIAs.

Cavernous malformations of the central nervous system: An international consensus statement.

Introduction: Cavernous malformations (CM) of the central nervous system constitute rare vascular lesions. They are usually asymptomatic, which has allowed their management to become quite debatable. Even when they become symptomatic their optimal mode and timing of treatment remains controversial. Research question: A consensus may navigate neurosurgeons through the decision-making process of selecting the optimal treatment for asymptomatic and symptomatic CMs. Material and methods: A 17-item questionnaire was developed to address controversial issues in relation to aspects of the treatment, surgical planning, optimal surgical strategy for specific age groups, the role of stereotactic radiosurgery, as well as a follow-up pattern. Consequently, a three-stage Delphi process was ran through 19 invited experts with the goal of reaching a consensus. The agreement rate for reaching a consensus was set at 70%. Results: A consensus for surgical intervention was reached on the importance of the patient's age, symptomatology, and hemorrhagic recurrence; and the CM's location and size. The employment of advanced MRI techniques is considered of value for surgical planning. Observation for asymptomatic eloquent or deep-seated CMs represents the commonest practice among our panel. Surgical resection is considered when a deep-seated CM becomes symptomatic or after a second bleeding episode. Asymptomatic, image-proven hemorrhages constituted no indication for surgical resection for our panelists. Consensus was also reached on not resecting any developmental venous anomalies, and on resecting the associated hemosiderin rim only in epilepsy cases. Discussion and conclusion: Our Delphi consensus provides an expert common practice for specific controversial issues of CM patient management.

Length of Survival, Outcome, and Potential Predictors in Poor-Grade Aneurysmal Subarachnoid Hemorrhage Patients Treated with Microsurgical Clipping.

BACKGROUND: Poor-grade aneurysmal subarachnoid hemorrhage (aSAH) has been associated with severe morbidity and high mortality. It has been demonstrated that early intervention is of paramount importance. The aim of our study is to evaluate the functional outcome and the overall survival of early microsurgically treated patients. MATERIAL AND METHODS: Poor-grade aSAH patients admitted at our institution over fifteen years (January 2008 - December 2022) were included in our retrospective study. All participants underwent brain Computed Tomography Angiography (CTA). Fisher scale was used to assess the severity of hemorrhage. All our study participants underwent microsurgical clipping, and their functional outcome was assessed with the Glasgow Outcome Scale (GOS). We used logistic regression analysis to identify any parameters associated with a favorable outcome at 12 months. Cox proportional hazard analysis was also performed, identifying factors affecting the length of survival. RESULTS: Our study included 39 patients with a mean age of 54 years. Thirty of our participants (76.9%) were Hunt and Hess grade V, while the vast majority (94.9%) were Fisher grade 4. The observed six-month mortality rate was 48.6%. The mean follow-up time was 18.6 months. The functional outcome at six months was favorable in 6 patients (16.2%), increased to 23.5% at 12 months. Our data analysis showed that the age, as well as the employment of temporary clipping during surgery, affected the overall outcome. CONCLUSION: Management of poor-grade aSAH patients has been dramatically changed. Microsurgical clipping provides promising results in carefully selected younger patients.

Investigation of risk factors for external ventricular drainage­associated central nervous system infections in patients undergoing neurosurgery.

Meningitis/ventriculitis (MV) is an illness which can occur as a complication following neurosurgical procedures. Devices such as an external ventricular drain (EVD) are also related to considerable complications, such as infections. The present study examined the risk factors associated with central nervous system (CNS) infections associated with the external ventricle drainage system. The present retrospective study included all patients hospitalized between April, 2011 and August, 2018 who had been receiving therapy with EVD for developed hydrocephalus. A total of 48 out of 65 patients were classified into two groups as follows: Patients without MV (group A) and patients who developed MV (group B). The durations of hospital stay and intensive care unit (ICU) stay were significantly lower in group A (32.4±24 and 21.1±11 days, respectively) compared to group B (54.7±37 and 42±24 days, respectively) (P=0.027 and P=0.001, respectively). The Acute Physiological and Chronic Health Evaluation II (APACHE II) score and EVD distance from the wound exit side to the burr hole were significantly lower in the survivors compared to the non-survivors (17.5±6 and 15.4±4 vs. 22.5±6 and 39.8±38, respectively). Receiver operating characteristic analysis revealed that the APACHE II score with an area under the curve [(AUC) of 0.677, P=0.044, and 95% confidence interval (CI) of (0.516-0.839)] and a cut-off value of 14 could predict mortality with a sensitivity of 100% and a specificity of 71%; the EVD distance from the wound exit side from the burr hole with an AUC of 0.694 (P=0.028), 95% CI of 0.521-0.866 and a cut-off value of 11.5 mm could predict mortality with a sensitivity of 88% and a specificity of 83%. On the whole, the present study demonstrates that the EVD-related distance from the wound exit side of the burr hole can predict poor outcomes due to CNS infections in patients undergoing neurosurgery.

Greek reflections on global neurosurgery.

Introduction: Large populations in middle- and low-income countries in Africa, Asia, and Central and South Americas face a dramatic neurosurgical crisis. However, large social groups in high-income countries face similar limited access to neurosurgical services. Proper identification of such a problem, analysis of the underlying causes, and proposal of potential solutions may not only address the problem at a national level, but may also provide valuable reflections on the efficient management of global neurosurgical crisis. Research question: To evaluate if special social groups face similar problems in Greece. Material and methods: The structure of the Greek health system was examined. The national census along with the registry of practicing neurosurgeons of the Greek National Society, as well as the national health map were searched. Results: A series of socio-economic factors, language barriers, cultural and religion differences, geographical barriers, the COVID-19 pandemic aftermath, along with the inherent malfunctioning of the Greek health system have led to this national neurosurgical crisis. Discussion and conclusion: An extensive redrawing of the Greek health map, reorganization of the national health system, along with adaptation of all recent advances in telemedicine may alleviate the health burden in these populations. The results of this local reformation may be applied to a global level for managing the ongoing health crisis. Moreover, the development of a European taskforce by the European Association of Neurosurgical Societies (EANS) may well facilitate the development of realistic and efficacious global solutions, and contribute to the global effort for providing high-quality neurosurgical services worldwide.

Bilateral Tapia's syndrome secondary to cervical spine injury: a case report and literature review.

A 24-year-old man presented with bilateral Tapia's syndrome (TS) after a traumatic cervical spine injury, manifested by apraxia of the hypoglossal and recurrent laryngeal nerves. The initial presentation was a profound inability to maintain upper respiratory airway patency due to bilateral vocal cord paralysis, accompanied by impairment of swallowing and loss of speech. The diagnosis was based on clinical grounds and verified by endoscopic laryngoscopy. A C7 corpectomy was performed for stabilizing the cervical spine, while conservative treatment with steroids was reserved for the TS. Over the following six months, there was complete resolution of the symptoms.

Posterior Fossa Intra-Axial Lesion: There Are Pathologies Beyond Metastases.

Cerebellar metastases represent the most common lesion requiring surgical treatment in the daily neurosurgical praxis. We report a rare case with Lhermitte-Duclos disease presenting to the neurosurgical outpatient department and describe our diagnostic and treatment challenges. A 57-year-old man presented with transient cerebellar manifestations, including walking difficulties, dizziness, and a persistent occipital headache. The magnetic resonance imaging demonstrated a high-intensity lesion in the right cerebellar hemisphere on T2-weighted images. We initially considered surgery to establish a histopathological diagnosis. However, the magnetic resonance spectroscopy was compatible with a dysplastic gangliocytoma of the cerebellum. Therefore, we preferred a more conservative approach. Posterior fossa contrast-enhancing lesions are much more than metastases. The role of advanced magnetic resonance in avoiding unnecessary surgical interventions is priceless.

Late-Onset Cervical Pseudomeningocele Following Ossification of the Posterior Longitudinal Ligament Surgery Successfully Treated With a Lumboperitoneal Shunt.

Pseudomeningocele (PMC) is a rare complication of anterior cervical procedures resulting in pain, headaches, nerve root entrapment, and in rare cases, spinal cord compression. Here we present a 57-year-old male with increasing myelopathy due to late-onset PMC that developed two years following a 360-degree cervical surgery for ossification of the posterior longitudinal ligament (OPLL). In this case, the PMC was successfully treated with a lumboperitoneal shunt. A 57-year-old male presented with worsening symptoms and signs of cervical myelopathy. He had undergone a multilevel anterior corpectomy/fusion (ACCF), along with posterior fusion, two years earlier for severe ossification of the posterior longitudinal ligament (OPLL). Now presenting with increased myelopathy, his cervical spine MRI demonstrated a PMC in the perivertebral space, extending to and compressing the anterior cervical cord. Following a lumboperitoneal shunt insertion, the patient's myelopathy resolved.  Acute, subacute, or chronic postoperative cervical pseudomeningoceles (PMC) may be readily managed with a lumboperitoneal shunt insertion.

The Role of Extra-Operative Cortical Stimulation and Mapping in the Surgical Management of Intracranial Gliomas.

BACKGROUND: Aggressive resection without compromising the patient's neurological status remains a significant challenge in treating intracranial gliomas. Our current study aims to evaluate the efficacy and safety of extra-operative stimulation and mapping via implanted subdural electrodes with or without depth (EOCSM), offering an alternative approach when awake mapping is contraindicated. METHODS: Fifty-one patients undergoing EOCSM for glioma resection in our institution formed the sample study of our current retrospective study. We assessed the effectiveness and safety of our approach by measuring the extent of resection and recording the periprocedural complications, respectively. RESULTS: The mean age of our participants was 58 years (±9.4 years). The lesion was usually located on the left side (80.4%) and affected the frontal lobe (51.0%). EOCSM was successful in 94.1% of patients. The stimulation and electrode implantation procedures lasted for a median of 2.0 h and 75 h, respectively. Stimulation-induced seizures and CSF leakage occurred in 13.7% and 5.9% of our cases. The mean extent of resection was 91.6%, whereas transient dysphasia occurred in 21.6% and transient hemiparesis in 5.9% of our patients, respectively. CONCLUSIONS: Extraoperative stimulation and mapping constitute a valid alternative mapping option in glioma patients who cannot undergo an awake craniotomy.

Dynamic Cervical Implants in Patients With Disc Degenerative Disease: A Single-Center Cohort From the Greek Population.

Aim The aim of this study was to review the safety and feasibility, clinical and radiological outcomes, and postoperative complications associated with the use of dynamic cervical implants (DCI). Patients and methods A prospective single-cohort study was performed of all consecutive patients who underwent DCI implantation as an adjunct to anterior cervical discectomy. We measured the anterior disc space height (ADH) and posterior disc space height (PDH), as well as the ADH/PDH ratio. Results In 11 patients, the ADH/PDH ratio averaged 0.98 (range: 0.7-1.125) postoperatively, from the initial 0.96 (range: 0.72-1.106). Conclusion DCI seems to be a viable alternative to anterior cervical discectomy and fusion. However, its role in motion preservation and protection against the degeneration of the adjacent segment is questioned.

Critical Appraisal of Randomized Controlled Trials on Unruptured Brain Arteriovenous Malformations.

OBJECTIVE: Brain arteriovenous malformations management remains controversial despite the numerous, available treatment options. Randomized controlled trials (RCTs) theoretically provide the strongest evidence for the assessment of any therapeutic intervention. However, poorly designed RCTs may be associated with biases, inaccuracies, and misleading conclusions. The purpose of our study is to assess reporting transparency and methodological quality of the existing RCTs. METHODS: A search was performed in the PubMed, Scopus, Embase, clinicaltrials.gov, and Cochrane databases. The search was limited to English literature. We included all published RCTs reporting on the management of unruptured brain arteriovenous malformations. The eligible studies were evaluated by 5 blinded raters with the CONsolidated Standards of Reporting Trials 2010 statement and the risk-of-bias 2 tool. The inter-rater agreement was assessed with the Fleiss' Kappa. RESULTS: A randomized trial of unruptured brain arteriovenous malformations (ARUBA) and treatment of brain arteriovenous malformations (TOBAS) trials were evaluated. ARUBA achieved high CONsolidated standards of reporting trials compliance, while TOBAS showed a moderate one. In ARUBA the introduction, discussion, and other information sections reached the highest compliance rate (80%-86%). The lowest rates were recorded in the results and the methods (62% and 73%, respectively). The inter-rater agreement was moderate to substantial (54.1% to 78.4%). All the examined studies demonstrated a high risk of bias, mainly related to ill-defined intended interventions, missing outcome data, and selection of the reported results. CONCLUSIONS: Our study confirmed the high risk of bias mainly attributed to several protocol violations, deviations, minimal external validity and selection, attrition, and allocation biases of the ARUBA trial. Analysis of the TOBAS trial revealed a moderate overall reporting clarity and a high risk of bias.

Dilemmas in managing coexisting arteriovenous and cavernous malformations: Case report.

Coexisting arteriovenous malformations (AVMs) and cavernous malformations (CMs) are rare. Here, we present our dilemmas in managing a patient with a cerebral AVM and a pontine CM. A 47-year-old patient suffered from headaches, vomiting, and transient swallowing difficulties. The cerebral computed tomography showed a pontine hyperintense lesion, while the axial magnetic resonance imaging of the head disclosed a frontal interhemispheric AVM and a CM located in the rostral and ventral aspect of the pons. Despite a pontine hemorrhage, the patient underwent microsurgical excision of the frontal lesion in the first place, due to the increased bleeding risk, followed by stereotactic radiosurgery of the pontine CM. On the 6 months follow-up, the patient's clinical status was stable. A reasonable treatment strategy based on risk stratification is paramount in managing patients with coexisting AVMs and CMs. The optimal outcome frequently requires a staged multidisciplinary approach.