The Current Landscape of Neurosurgical Oncology in Low-Middle-Income Countries (LMIC): Strategies for the Path Forward.

OBJECTIVE: To promote global equity in research, innovation, and care, sharing knowledge and grasping current benchmarks is crucial. Despite LIC/LMIC constituting around 80% of the global population, their contribution to neurosurgery research is less than 5%. This study aims to assess the status of neurosurgical oncology in LIC/LMIC using published data, offering strategic insights for progress. METHODS: Conducting a retrospective bibliometric analysis via PubMed and Scopus databases, we documented reports published (2015-2021) by neurosurgical department-affiliated investigators in LICs/LMICs. World Bank classifications identified LIC and LMIC. Reviewed papers underwent further scrutiny based on independent and associated keyword lists. RESULTS: Our systematic approach revealed 189 studies from LMIC in 10 neurosurgery journals. Of these, 53% were case reports, with 88% focusing on brain pathologies and 12% on the spine. Intra-axial brain tumors (45.8%), extra-axial/skull base (38.4%), and metastasis (3.68%) were prominent. Among noncase report publications, surgical technique and outcome were common themes. India, Egypt, and Tunisia led in publications, with 94% appearing in journals with an impact factor below 5. No papers originated from LIC. CONCLUSIONS: This study reinforces existing findings that data from LMIC inadequately represent their populations, impeding a comprehensive understanding of their neurosurgical oncology landscape. Language barriers and data collection difficulties contribute to this gap. Addressing these challenges could significantly enhance progress in shaping the future of neurosurgical oncology in these regions.

Spinal navigation for small thoracic intradural tumors: The challenge between minimally invasive and exoscopic magnification.

Background: Spinal navigation offers significant benefits in the surgical treatment of small thoracic intradural tumors. It enables precise tumor localization without subjecting the patient to high radiation doses. In addition, it allows for a smaller skin incision, reduced muscle stripping, and limited bone removal, thereby minimizing the risk of iatrogenic instability, blood loss, postoperative pain, and enabling shorter hospital stays. Case Description: This video presents two cases demonstrating the application of spinal navigation technique for thoracic intradural tumors measuring <20 mm. In the first case, which involves a small calcified tumor, navigation can be performed using 3D fluoroscopy or computed tomography images obtained intraoperatively. Notably, as illustrated in the second case, the merging of preoperative magnetic resonance imaging images with intraoperative 3D fluoroscopy enables navigation in the context of soft intradural lesions as well. The setup of the operating room for these procedures is also depicted. Conclusion: In these procedures, the use of an exoscope, in addition to the well-known advantages in terms of magnification and ergonomics, provides a large space of movement around the surgical field, with greater ease in the use of navigation devices and ultrasound. The minimal invasiveness of the surgical approach is in no way a hindrance to exoscopic visualization and surgical dissection.

Growth and rupture of an intracranial aneurysm: the role of wall aneurysmal enhancement and CD68.

Introduction: Intracranial aneurysms occur in 3%-5% of the general population. While the precise biological mechanisms underlying the formation, growth, and sudden rupture of intracranial aneurysms remain partially unknown, recent research has shed light on the potential role of inflammation in aneurysm development and rupture. In addition, there are ongoing investigations exploring the feasibility of employing new drug therapies for controlling the risk factors associated with aneurysms. CD68, a glycosylated glycoprotein and the human homolog of macrosialin, is prominently expressed in monocyte/macrophages within inflamed tissues and has shown potential application in oncology. An observational study was conducted with the aim of comparing the histological characteristics of aneurysm walls with preoperative MRI scans, specifically focusing on CD68 activity. Method: An observational pilot study was conducted to investigate the histological characteristics of the aneurysm wall that could be potentially associated with aneurysm growth and rupture. A total of 22 patients diagnosed with ruptured and unruptured intracranial aneurysms who had undergone conventional clipping between January 2017 and December 2022 were included in the study. Results: A histopathological analysis of the aneurysm wall was performed in all patients, particularly focusing on the presence of CD68. A preoperative MRI with gadolinium was conducted in 10 patients with unruptured aneurysms and six patients with ruptured aneurysms. An emergency clipping was performed in the remaining six patients. The results showed that CD68 positivity and wall enhancement were significantly associated with intracranial aneurysm wall degeneration, growth, and rupture. Conclusion: The histological and radiological inflammatory findings observed in the wall of cerebral aneurysms, as well as the CD68 positivity, are significantly associated with the risk of intracranial aneurysm growth and rupture. This study highlights the crucial importance of considering clinical and medical data when making treatment decisions for intracranial aneurysms. Furthermore, it emphasizes the relevance of evaluating wall enhancement in MRI scans as part of the diagnostic and prognostic process.

The lumbar adjacent-level syndrome: analysis of clinical, radiological, and surgical parameters in a large single-center series.

OBJECTIVE: The development of specific clinical and neurological symptoms and radiological degeneration affecting the segment adjacent to a spinal arthrodesis comprise the framework of adjacent-level syndrome. Through the analysis of a large surgical series, this study aimed to identify possible demographic, clinical, radiological, and surgical risk factors involved in the development of adjacent-level syndrome. METHODS: A single-center retrospective analysis of adult patients undergoing lumbar fusion procedures between January 2014 and December 2018 was performed. Clinical, demographic, radiological, and surgical data were collected. Patients who underwent surgery for adjacent-segment disease (ASD) were classified as the ASD group. All patients were evaluated 1 month after the surgical procedure clinically and radiologically (with lumbar radiographs) and 3 months afterward with CT scans. The last follow-up was performed by telephone interview. The median follow-up for patients included in the analysis was 67.2 months (range 39-98 months). RESULTS: A total of 902 patients were included in this study. Forty-nine (5.4%) patients required reoperation for ASD. A significantly higher BMI value was observed in the ASD group (p < 0.001). Microdiscectomy and microdecompression procedures performed at the upper or lower level of an arthrodesis without fusion extension have a statistically significant impact on the development of ASD (p = 0.001). Postoperative pelvic tilt in the ASD group was higher than in the non-ASD group. Numeric rating scale, Core Outcome Measures Index, and Oswestry Disability Index scores at the last follow-up were significantly higher in patients in the ASD group and in patients younger than 65 years. CONCLUSIONS: Identifying risk factors for the development of adjacent-level syndrome allows the implementation of a prevention strategy in patients undergoing lumbar arthrodesis surgery. Age older than 65 years, high BMI, preexisting disc degeneration at the adjacent level, and high postoperative pelvic tilt are the most relevant factors. In addition, patients older than 65 years achieve higher levels of clinical improvement and postsurgical satisfaction than do younger patients.

Tuberculum sellae meningiomas: surgical outcomes in 65 patients, review of the literature and proposal for an anatomical and radiological classification.

Tuberculum sellae meningiomas (TSM) are challenging tumors due to their proximity to vital neurovascular structures. We propose a new classification system based on anatomical and radiological parameters. All patients treated for TSM, between January 2003 and December 2016, have been retrospectively reviewed. A systematic research was performed in PubMed database to review all studies comparing the performance of transcranial (TCA) and transphenoidal (ETSA) approaches. Overall, 65 patients were included in the surgical series. Gross total removal (GTR) was achieved in 55 patients (85%) and near total resection in 10 (15%). 54 patients (83%) showed a stability or an improvement of visual functions and 11 (17%) worsened. Postoperative complications were observed in seven patients (11%): CSF leak in one patient (1.5%); diabetes insipidus in two (3%); hypopituitarism in two (3%) third cranial nerve paresis and subdural empyema in one (1.5%). For the literature review, data about 10,833 patients (TCA N.=9159; ETSA N.=1674) were recorded; GTR was achieved in 84.1% (range 68-92%) of TCA and in 79.1% (range 60-92%) of ETSA; visual improvement (VI) occurred in 59.3% of TCA (range 25-84%) and in 79.3% of ETSA (range 46-100%); visual deterioration (VD) was registered in 12.7% of TCA (0-24%) and in 4.1% of ETSA (range 0-17%); a CSF-leak was observed in 3.8% of TCA (range 0-8%) while in ETSA in 18.6% of patients (range 0-62%); vascular injuries was reported in 4% (range 0-15%) of TCA and in 1.5% (range 0-5%) of ETSA. In conclusion, TSMs represent a unique category of midline tumors. The proposed classification system provides an intuitive and reproducible method in the choice of the most suitable approach.

Intracranial Hypotension Syndrome after Lumbar Drainage in Skull Base Surgery: Diagnosis and Correct Management.

Lumbar drainage is commonly used in skull base surgery; however, very few cases of intracranial hypotension syndrome are reported to be caused by this procedure. We present a clinical case of lumbar drainage-assisted orbital and optic canal decompression surgery for a recurrent voluminous spheno-orbital meningioma, together with a literature review. A 49-year-old woman became confused and drowsy on postoperative day 3, after initially experiencing neurologic stability. Computed tomography (CT) scan of the head showed extradural frontotemporal fluid collection with moderate right to left midline shift. Magnetic resonance imaging (MRI) of the brain showed signs of intracranial hypotension, such as brain sagging and diffuse dural contrast enhancement. Conservative treatment with bed rest, aggressive hydration, steroids, and aminophylline led to progressive neurologic improvement. A systematic literature review was also performed, and previous reported cases were analyzed. Overall, neurosurgeons must be aware of the lumbar drainage-induced hypotension syndrome in skull base surgeries, because immediate diagnosis is essential for therapeutic decision-making. In this setting, conservative management is the first-line treatment as surgery may lead to severe complications.

Pain and Quality of Life in Patients Undergoing Lumbar Arthrodesis for Degenerative Spondylolisthesis: A Systematic Review.

BACKGROUND: Degenerative spondylolisthesis is a disease characterized by the displacement of a vertebra above the underlying vertebra. Lumbar arthrodesis is currently the most frequently performed surgical option for treatment due to the use of various approaches and techniques. The disease is characterized by low back pain, a clinical and public health problem, which in addition to having a socio-economic burden, severely affects functional status, quality of life (QoL), activity impairment, and health services. The study aims to investigate the benefits, in terms of pain, disability, andQoL, of lumbar arthrodesis surgery in patients with degenerative spondylolisthesis, at the latest follow-up. METHODS: A systematic literature review registered in PROSPERO (ID: CRD42022379242), was conducted in the databases of: Cochrane Library, PubMed, Embase, Scopus, and Web of Science. The key words used were as follows: "spondylolisthesis", "arthrodesis", "degenerative", "quality of life", "pain", "patient reported outcome", and "disability". RESULTS: A total of 26 articles were included. Significant differences were found between the preoperative and postoperative evaluation of the outcomes considered, in particular: pain (MD = -6.74; SD = 2.83; 95% CI: -8.01 to -5.46), low back pain (MD = -3.35; SD = 3.27; 95% CI: -3.61 to -3.10), lower limb pain (MD = -3.81; SD = 3.80; 95% CI: -4.10 to -3.51), disability (MD = -23.75; SD = 19.68; 95% CI: -25.26 to -22.23) and QoL (MD = 0.21; SD = 0.24; 95% CI: 0.19 to 0.23). CONCLUSIONS: The results show significant improvement in all measured variables, demonstrating that there are different surgical treatments to cure degenerative spondylolisthesis. However, residual pain impacting the QoL remains, regardless of the technique used. Therefore, the development of personalized pain management for patients with residual chronic pain is indicated.

Applicability and efficacy of ultrasound elastography in neurosurgery: a systematic review of the literature.

INTRODUCTION: Neurosurgery is one of the fields in which intraoperative imaging is paramount. One of these main imaging tools that have been acquiring the interest of the neurosurgical community is Ultrasound elastography (USE), which is an imaging technology sensitive to tissue stiffness. Here we present a systematic review of the use of USE in neurosurgery. EVIDENCE ACQUISITION: A systematic review of the literature has been performed, according to the PRISMA guideline, for the last 30 years on 3 different databases (MEDLINE, Scopus, and Cochrane), to gather all the studies on the use of ultrasound elastography for neurosurgical pathologies, including both clinical and laboratory studies. EVIDENCE SYNTHESIS: A total of 15 articles met the inclusion criteria. USE has widely and safely been used especially for oncological lesions (meningiomas and gliomas) and focal cortical dysplasia. However, there are also encouraging laboratory studies about its application for the management of traumatic brain injury, and ischemic stroke. CONCLUSIONS: This systematic review showed that, despite the lack of strong evidence, USE is a valid intraoperative tool, especially in oncological neurosurgery.

Lumbar adjacent segment degeneration after spinal fusion surgery: a systematic review and meta-analysis.

INTRODUCTION: Adjacent segment degeneration is among the most recognized long-term complications of lumbar surgery for degenerative spine pathologies with a relevant impact in spine surgical and clinical practice. It is reported a incidence of clinical adjacent segment disease between 5-30% of patients undergoing spinal fusion. We aimed to evaluate the main clinical and surgical risk factors for developing adjacent segment disease. EVIDENCE ACQUISITION: A systematic review and meta-analysis of the pertinent literature was performed, according to PRISMA and PICO guidelines, focusing on clinical and radiological adjacent segment disease. We exclusively included studies reporting demographic and clinical data, and surgical details published from 30 September 2015 to 30 September 2020. The effect of considered risk factors on the presence of adjacent segment disease was explored with a random-effects model. EVIDENCE SYNTHESIS: A total of 15 scientific publications, corresponding to 6253 patients, met the inclusion criteria for the qualitative and quantitative analysis. 720 of the patients developed a clinical and/or radiological adjacent syndrome disease, and 473 have been surgically managed. Ten articles qualified for the comparative geographical analysis. Advanced age and obesity are relevant risk factors for developing lumbar adjacent segment degeneration. Our data also reported a higher prevalence of adjacent segment degeneration in Western populations than in Eastern populations. The interbody fusion has a protective role toward lumbar adjacent segment degeneration. CONCLUSIONS: This study highlighted multifactorial issues regarding adjacent segment disease: clinical, anatomical, biomechanical, and radiological features. In view of increasing life expectancy and spinal surgery procedures, extensive multicenter studies will be needed to define the correct management of the adjacent segment disease.

The efficacy of laser interstitial thermal therapy in the management of spinal metastases: a systematic review of the literature.

BACKGROUND: In the last years, laser interstitial thermal therapy (LITT) has started to be used also in neurosurgical setting. Its efficacy for intracranial pathologies, namely, tumors and epilepsy, has been widely demonstrated. However, the literature evidences about the use of LITT for spinal lesions are recent, and it is still a topic of discussion regarding its efficacy. Here, the authors sought to present a systematic review of the literature investigating the utility of LITT for spinal lesions. METHODS: Using PubMed, Scopus, and the Cochrane Library, the authors performed a systematic review of the literature focused on the use of spinal laser interstitial thermal therapy (sLITT). Included in the search were randomized controlled trials, cohort studies, and clinical series. Two independent reviewers conducted the study appraisal, data abstraction, and quality assessments of the studies. RESULTS: Out of the initial 134 studies, 6 met the inclusion criteria for the systematic review, resulting in a total of 206 patients. All the patients have been treated with sLITT for compressive spinal metastases. Most of the lesions were thoracic (88.8%). All the studies reported an effective local control of the disease with a reduction of epidural compression at 30 days. Complication rate was 12.6%, but most of them were transient conditions, and only 3.4% patients needed a revision surgery. CONCLUSION: sLITT is safe and provides effective local control for epidural compression from metastases, particularly in the thoracic spine. The authors propose considering sLITT as an alternative to open surgery in selected patients with spinal metastases.

Second Footprint of Reports from Low- and Low- to Middle-Income Countries in the Neurosurgical Data: A Study from 2018-2020 Compared with Data from 2015-2017.

OBJECTIVE: In 2019, we highlighted the disparities in scientific production between high-income countries (HICs) and low- to middle-income countries (LMICs) by emphasizing how scientific research was underrepresented in the latter. The present study aimed to investigate research productivity in neurosurgery of low-income countries (LICs) and LMICs for the years 2018-2020 and to compare it with the results of our previous study for 2015-2017. METHODS: We performed a retrospective bibliometric analysis using PubMed and Scopus databases to record all the reports published in 2018-2020 by investigators affiliated with neurosurgical departments in LICs and LMICs. The attribution of the study to LMICs was based on the presence of either the first author or the majority of authors. RESULTS: Our systematic search identified 486 studies reported by LICs and LMICs for full text examination in 12 journals. These articles represent 4.9% of all published neurosurgical articles, compared with 4.5% in the 2015-2017 study. India remained the country with the highest contribution, with a 17.1% increase in reports. Other countries, such as Nigeria and Philippines, also show an increased percentage of reports (from 0.9% to 3.7% and from 0.6% to 2.1%, respectively). CONCLUSIONS: There is growing consensus in the neurosurgical scientific community that the dissemination and analysis of epidemiologic and clinical data from developing countries can provide guidelines and practical suggestions worldwide. However, our study shows that the number of neurosurgical articles published by low-income countries in 2018-2020 remained at approximately 5% of the total, resulting in a negative impact on the process of globalization.

IV and V grade arteriovenous Malformations: A multicenter surgical experience. Use of multiple grading system to predict surgical risk.

OBJECTIVE: The aim of our study is to report a multicenter experience in the treatment of IV and V grade arteriovenous malformations (AVMs) and to apply commonly used grading scales for surgical risk assessment for these vascular high-grade lesions. METHODS: Between January 2015 and December 2019, a retrospective study was conducted to identify patients undergoing microsurgical intervention for cAVMs at two Italian centers specialized in the treatment of vascular pathologies. Data on patients with Spetzler-Martin IV and V and with a score equal or more than 7 according to Lawton-Young classification were collected. Ruptured AVMs at admission were subsequently classified according to the new proposed AVICH classification. RESULTS: A total of 20 patients with high grade (IV and V) cAVMs were enrolled in the study and the average follow-up was 36.45 months. The outcome based on mRS was favorable in 65 % of cases. The pre-operative mRS was a factor influencing clinical outcome, as well as the number of bleedings preceding the treatment, age, and nidus characteristics. S-M IV, L-Y 3 and S-M supp 7 scores were associated with good outcome. Based on the AVICH classification, for ruptured cAVMs, having a score of 9 ore less was correlated to a postoperative mRS fewer or equal than 2. CONCLUSIONS: Surgical management for high-grade AVMs should be considered in highly selected patients with repeated bleeding or disabling symptoms. Classification systems provide an aid in selecting patients for surgery, also in grade IV and V. It is essential to establish common registers for the management of these complex vascular malformations.

Prevalence of Postoperative Complications of Autologous and Heterologous Cranioplasty in the Pediatric Population: A Systematic Review of the Literature.

INTRODUCTION: Cranial reconstruction (CR) is a neurosurgical procedure performed to restore the cranial vault after a decompressive craniectomy. There are contrasting reports from the literature about the complications related to the use of heterologous materials for CR in the pediatric population. In this study, the authors try to better define such a rate of adverse events for autologous and heterologous materials. MATERIALS AND METHODS: A systematic review of articles published up to December 2021 was performed. Studies were included if they reported the specific use of cranioplasty materials following craniectomy in patients younger than 18 years of age and had a minimum follow-up of at least 1 year. RESULTS: A total of 20 studies were selected. A total of 544 cases were included, of which 422 (77.6%) were with heterologous materials and 122 (22.4%) with autologous bone. The mean average age was 9.5 years. Polyetheretherketone and polymethylmethacrylate reported 29% and 33.3%, respectively, of complications, but only 3% and 5.6% of surgical revision. PHA reported a rate of 11.9%. Titanium reported 9.2% of complications and 4.1% of surgical revisions. Porous polyethylene had a complication rate of 36.4% and a revision rate of 0%. CONCLUSION: There is still no perfect material for CR. It seems that heterologous materials are superior to autologous bone for CR in children, and we may consider, whenever economic conditions will allow it, to use alloplastic material as first-line in small children.

Augmented Reality in Neurosurgery, State of Art and Future Projections. A Systematic Review.

Background: The use of augmented reality (AR) is growing in medical education, in particular, in radiology and surgery. AR has the potential to become a strategic component of neurosurgical training courses. In fact, over the years, there has been a progressive increase in the application of AR in the various fields of neurosurgery. In this study, the authors aim to define the diffusion of these augmented reality systems in recent years. This study describes future trends in augmented reality for neurosurgeons. Methods: A systematic review of the literature was conducted to identify research published from December 1st, 2011 to November 30th, 2021. Electronic databases (PubMed, PubMed Central, and Scopus) were screened. The methodological quality of studies and extracted data were assessed for "augmented reality" and "neurosurgery". The data analysis focused on the geographical distribution, temporal evolution, and topic of augmented reality in neurosurgery. Results: A total of 198 studies have been included. The number of augmented reality applications in the neurosurgical field has increased during the last 10 years. The main topics on which it is mostly applied are spine surgery, neuronavigation, and education. The geographical distribution shows extensive use of augmented reality in the USA, Germany, China, and Canada. North America is the continent that uses augmented reality the most in the training and education of medical students, residents, and surgeons, besides giving the greatest research contribution in spine surgery, brain oncology, and surgical planning. AR is also extensively used in Asia for intraoperative navigation. Nevertheless, augmented reality is still far from reaching Africa and other countries with limited facilities, as no publications could be retrieved from our search. Conclusions: The use of AR is significantly increased in the last 10 years. Nowadays it is mainly used in spine surgery and for neurosurgical education, especially in North America, Europe and China. A continuous growth, also in other aspects of the specialty, is expected in the next future.

A Multicentric European Clinical Study on Custom-Made Porous Hydroxyapatite Cranioplasty in a Pediatric Population.

Background: Cranioplasty (CP) is a surgical intervention aiming to re-establish the integrity of skull defects. Autologous bone and different heterologous materials are used for this purpose, with various reported related complications, especially in children.This study aims to evaluate the rate of complication in a multicentric cohort of pediatric patients treated by porous hydroxyapatite (PHA) CP implantation and to assess the reliability of post-marketing clinical data collected by a manufacturing company. Methods: The authors proactively collected clinical data from 20 institutions in different European countries for patients under the age of 16 treated with a PHA implant. The data were obtained by conducting an on-site interview with physicians in charge of the patients (Post-Marketing Surveillance, PMS group). The endpoints were the incidence of adverse events and related implant removal. The clinical data were compared to the company-based register including all patients under the age of 16 who received the same implant from January 1, 2004 to December 31, 2020, and the collecting complications voluntarily reported by surgeons (Database, DB group). Results: The two groups were similar in terms of demographic characteristics and rate of complications. In the PMS group, a total of 11 (16.9%) complications were reported in the group of 65 patients that were proactively collected. Both fractures and infections were the most common complications with 4 cases each (6.2%). In the case of both infections and fractures, revision surgery was required for only one patient (1.5%). Three (4.5%) cases of displacements were reported, and in one (1.5%) case, a surgical revision was required, for a total of 3 (4.5%) cases requiring surgical revision. The average follow-up was 26.7 months. Conclusions: Different from a previous study on adult age, pediatric neurosurgeons are more prone to report even to the manufacturing company complications related to skull reconstruction in children. Therefore, these data can be compared with those of other clinical studies. The PHA CP in this series of 65 patients presents a complication rate collected on-site that is similar to other heterologous materials.

Tentorial Notch Meningiomas: Innovative Preoperative Management and Literature Review.

Background: Tentorial meningiomas account for only 3-6% of all intracranial meningiomas. Among them, tentorial incisura (notch) location must be considered as a subgroup with specific surgical anatomy and indications, morbidity, and mortality. In this study, we propose an update on preoperative management in order to reduce postoperative deficits. Methods: We retrospectively collected adult patients treated for incisural meningioma between January 1992 and December 2016 in two different neurosurgical departments. Demographic, clinical, and neuroradiological preoperative and postoperative data were analyzed. In the most recent subgroup of tumors, a preoperative digital simulation was performed to define a volumetric digital quantification of the tumor resection. A review of the pertinent literature has been also done. Results: We included 26 patients. The median age was 58.4 years. Onset neurological signs were cranial nerve deficit in 9 patients, hemiparesis in 7, gait disturbance in 3, and intracranial hypertension in 3 patients. Simpson grade I removal was achieved in 12 patients, II in 10, III in 3, and IV in 1 patient. An overall rate of 23% postoperative complications was observed. The average follow-up duration was 68.5 months. Residual tumor was reported in 8 patients. Five patients underwent gamma knife radiosurgery. In 34.6% of patients, the surgical approach was chosen with preoperative digital planning estimating the potential volume of postoperative residual tumor, the target for radiosurgical treatment. Conclusions: A multidisciplinary approach to plan incisural meningiomas management is important. To lower postoperative morbidity and mortality, a careful preoperative case analysis is useful. A planned residual tumor, supported by preoperative simulation imaging, could be safely treated with radiosurgery.