Editorial for Brain Sciences Special Issue: "Advances in Skull Base Tumor Surgery: The Practical Pearls".

The field of skull base surgery is unique; it involves the adequate and coordinated multidisciplinary interaction of multiple specialties, such as otorhinolaryngology, maxillofacial surgery, ophthalmology, neuro-anesthesiology, oncology, radiation oncology, neurophysiology, and neurosurgery [...].

Toward a Frontierless Collaboration in Neurosurgery: A Systematic Review of Remote Augmented and Virtual Reality Technologies.

OBJECTIVE: Augmented reality (AR) and virtual reality (VR) technologies have been introduced to neurosurgery with the goal of improving the experience of human visualization. In recent years, the application of remote AR and VR has opened new horizons for neurosurgical collaboration across diverse domains of education and patient treatment. Herein, we aimed to systematically review the literature about the feasibility of this technology and discuss the technical aspects, current limitations, and future perspectives. METHODS: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, 4 databases (PubMed, Embase, Scopus, and Cochrane Library) were queried for articles discussing the use of remote AR and VR technologies in neurosurgery. Data were collected in various fields, including surgery type, application type, subspecialty, software and hardware descriptions, haptic device utilization, visualization technology, internet connection, remote site descriptions, technical outcomes, and limitations. Data were summarized as counts and proportions and analyzed using IBM SPSS software. RESULTS: Our search strategy generated 466 records, out of which 9 studies satisfied the inclusion criteria. The majority of AR and VR applications were used in cranial procedures (77.8%), mainly in education (63.6%), followed by telesurgical assistance (18.2%), patient monitoring (9.1%), and surgical planning (9.1%). Local collaborations were established in 55.6% of the studies, while national and international partnerships were formed in 44.4% of the studies. AR was the main visualization technology, and 3G internet connection was predominantly used (27.5%). All studies subjectively reported the utility of remote AR and VR for real-time interaction. The major technical challenges and limitations included audiovisual latency, the requirement for higher-fidelity and resolution image reconstructions, and the level of proficiency of the patient with the software. CONCLUSIONS: The results from this systematic review suggest that AR and VR technologies are dynamically advancing to offer remote collaboration in neurosurgery. Although still incipient in development and with an imperative need for technical improvement, remote AR and VR hold a frontierless potential for patient monitoring, neurosurgical education, and long-distance surgical assistance.

Stroke Prevention in Blunt Cerebrovascular Injury: Role of Aspirin 81 mg.

BACKGROUND: The stroke rate in blunt cerebrovascular injury (BCVI) varies from 25% without treatment to less than 8% with antithrombotic therapy. There is no consensus on the optimal management to prevent stroke BCVI. We investigated the efficacy and safety of oral Aspirin (ASA) 81 mg to prevent BCVI-related stroke compared to historically reported stroke rates with ASA 325 mg and heparin. METHODS: A single-center retrospective study included adult trauma patients who received oral ASA 81 mg for BCVI management between 2013 and 2022. Medical records were reviewed for demographic and injury characteristics, imaging findings, treatment-related complications, and outcomes. RESULTS: Eighty-four patients treated with ASA 81 mg for BCVI were identified. The mean age was 41.50 years, and 61.9% were male. The mean Injury Severity Score and Glasgow Coma Scale were 19.82 and 12.12, respectively. A total of 101 vessel injuries were identified, including vertebral artery injuries in 56.4% and carotid artery injuries in 44.6%. Traumatic brain injury was found in 42.9%, and 16.7% of patients had a solid organ injur. Biffl grade I (52.4%) injury was the most common, followed by grade II (37.6%) and grade III (4.9%). ASA 81 mg was started in the first 24 hours in 67.9% of patients, including 20 patients with traumatic brain injury and 8 with solid organ injuries. BCVI-related stroke occurred in 3 (3.5%) patients with Biffl grade II (n = 2) and III (n = 1). ASA-related complications were not identified in any patient. The mean length of stay in the hospital was 10.94 days, and 8 patients died during hospitalization due to complications of polytrauma. Follow-up with computed tomography angiography was performed in 8 (9.5%) patients, which showed improvement in 5 and a stable lesion in 3 at a mean time of 58 days after discharge. CONCLUSIONS: In the absence of clear guidelines regarding appropriate medication, BCVI management should be individualized case-by-case through a multidisciplinary approach. ASA 81 mg is a viable option for BCVI-related stroke prevention compared to the reported stroke rates (2%-8%) with commonly used antithrombotics like heparin and ASA 325 mg. Future prospective studies are needed to provide insight into the safety and efficacy of the current commonly used agent in managing BCVI.

Unusual presentation of glioblastoma in the brainstem: a case report of a diffuse pontine glioblastoma multiforme and surgical management.

Diffuse pontine glioblastoma multiforme is a rare subtype of glioblastoma associated with a poor prognosis. In this case report, we present a unique case of diffuse primary pontine glioblastoma multiforme in a patient without any supratentorial lesions. We review the symptoms, treatment options, and case management of patients with infratentorial glioblastoma multiforme and compare these with our patient. Our patient presented with symptoms including progressive diplopia, gait disturbance, and lower extremity weakness. Magnetic resonance imaging revealed a diffuse lesion involving the pons and biopsy revealed only mildly-atypical glial infiltrates. Consequentially, diagnosis was driven by genetic analysis. Due to the location of the tumor, surgery was not considered a viable option. Instead, the patient received radiation therapy along with concomitant and adjuvant temozolomide chemotherapy which has resulted in improvement of symptoms. This case highlights the challenges of managing diffuse primary pontine glioblastoma multiforme and the need for more effective treatment options for this rare subtype of glioblastoma. Despite aggressive treatment, the prognosis for patients with infratentorial glioblastoma multiforme remains poor, with a median survival time of less than a year. Further research is needed to improve our understanding of the biology and optimal management of this disease.

Isolated cervical Cutibacterium acnes osteomyelitis in a patient with no primary source of infection - A case report and review of the literature.

Background: Cervical vertebral osteomyelitis (CVO) is a rare pathology that leads to progressive osseous degradation and eventual loss of bone putting the patient at risk of devastating neurological injury in the event of bony collapse or instability. Cutibacterium acnes formerly called Propionibacterium acnes is rare, but within the last two decades has been an increasingly reported cause of osteomyelitis. The majority of C. acnes vertebral osteomyelitis cases have been reported in patients with a history of prior invasive procedures where direct contamination at the time of procedure was suspected as the underlying etiology. Case Description: We report a unique case of an otherwise healthy 39-year-old male with no prior history of invasive procedures who presented with CVO secondary to C. acnes. He underwent surgical debridement and fusion in conjunction with antibiotic treatment. The patient recovered well and a 2-year follow-up with serial imaging showed no evidence of disease recurrence. Conclusion: C. acnes is an under-recognized and under-reported etiology of spine infections. Clinicians should be aware of the pathological potential and atypical presentation of C. acnes vertebral osteomyelitis.

Giant primary intracranial multi-fossa leiomyosarcoma involving the frontal sinus, ethmoid air cells, anterior fossa, middle fossa, and intraventricular space: A case report and literature review.

Background: Leiomyosarcomas (LMSs) is a type of sarcoma that arises from smooth muscle and generally presents in the abdomen. Although intracranial LMS has been identified before, most reported presentations have been in immunocompromised patients. Here, we present an intracranial LMS in an immunocompetent patient. Case Description: A 22-year-old male with a history of an atypical pineal parenchymal tumor of intermediate differentiation resected by suboccipital craniotomy at the age of 12 followed by adjuvant radiation therapy, presented with 3 weeks of decreased appetite, weight loss, and lethargy. He subsequently underwent transbasal approach skull base tumor resection. Histologic examination of the mass along with the patient's history of radiation was supportive of a low-grade, radiation-induced LMS arising from the anterior fossa of the skull or meninges and extends to the frontal sinus and ethmoid air cells. Conclusion: Primary intracranial LMS is an extremely rare diagnosis and presenting symptoms vary with the location and size of the tumor. Due to the poor specificity of clinical symptoms, diagnosis is often based on histology. The most common treatment is surgical resection. Adjuvant chemotherapy with various agents has been found to be somewhat effective outside the central nervous system. When LMS does occur, a history of immunocompromised state or previous radiation exposure is often present. Pathological confirmation is required for an appropriate diagnosis.

Percutaneous high cervical spinal cord stimulation for refractory trigeminal neuralgia.

Background: Trigeminal neuralgia (TN) is a debilitating pain that affects the dermatomes associated with the trigeminal nerve (V1, V2, and V3). Unfortunately, many medical treatments and surgical procedures fail to sufficiently modulate the pain associated with this condition. Case Description: This study presents two extreme cases of refractory TN (RTN) that progressed to atypical facial pain and describes successful mitigation of the neuralgia of said cases by percutaneous implantation of upper cervical spinal cord stimulation (SCS). The SCS was designed to target the descending spinal trigeminal tract. Conclusion: Together, these cases collaborate with the limited literature and further delineate the use and potential advantages of SCS in the treatment of RTN.

Staged Strategies to Deal with Complex, Giant, Multi-Fossa Skull Base Tumors.

Given the complex and multifaceted nature of resecting giant tumors in the anterior, middle, and, to a lesser extent, the posterior fossa, we present two example strategies for navigating the intricacies of such tumors. The foundational premise of these two approaches is based on a two-stage method that aims to improve the visualization and excision of the tumor. In the first case, we utilized a combined endoscopic endonasal approach and a staged modified pterional, pretemporal, with extradural clinoidectomy, and transcavernous approach to successfully remove a giant pituitary adenoma. In the second case, we performed a modified right-sided pterional approach with pretemporal access and extradural clinoidectomy. This was followed by a transcortical, transventricular approach to excise a giant anterior clinoid meningioma. These cases demonstrate the importance of performing staged operations to address the challenges posed by these giant tumors.

Delayed revascularization in acute ischemic stroke patients.

Stroke shares a significant burden of global mortality and disability. A significant decline in the quality of life is attributed to the so-called post-stroke cognitive impairment including mild to severe cognitive alterations, dementia, and functional disability. Currently, only two clinical interventions including pharmacological and mechanical thrombolysis are advised for successful revascularization of the occluded vessel. However, their therapeutic effect is limited to the acute phase of stroke onset only. This often results in the exclusion of a significant number of patients who are unable to reach within the therapeutic window. Advances in neuroimaging technologies have allowed better assessment of salvageable penumbra and occluded vessel status. Improvement in diagnostic tools and the advent of intravascular interventional devices such as stent retrievers have expanded the potential revascularization window. Clinical studies have demonstrated positive outcomes of delayed revascularization beyond the recommended therapeutic window. This review will discuss the current understanding of ischemic stroke, the latest revascularization doctrine, and evidence from clinical studies regarding effective delayed revascularization in ischemic stroke.

Basilar apex aneurysm systematic review: Microsurgical versus endovascular treatment.

BACKGROUND: Both microsurgical and endovascular techniques continued to be treatment options for basilar apex aneurysms (BAA). We conducted a systematic review to compare both treatment options in terms of both clinical and radiological outcomes. METHODS: The PRISMA method was used to identify related articles. Data collected from each article and the two treatment approaches were compared in terms of favorable clinical outcome and complete/near complete occlusion rate. Subgroup analysis was done based on the size and the rupture status of BAA. RESULTS: Fifty-nine (59) and 32 articles reported a measurable clinical and radiological outcome respectively. The weighted average favorable clinical outcome was significantly higher in the endovascular group (86.4% vs 79.6%, P<0.0001), while the weighted average complete/near complete occlusion rate was significantly higher in the surgical group (92.6% vs 83.8%, P<0.0001). In the subgroup analysis, the favorable clinical outcome remained significantly higher in the endovascular group for the ruptured, unruptured and giant/large BAA (P<0.001), but not in the small BAA subgroup (P=0.26). The occlusion rate remained significantly higher in the surgical group for all subgroups (P<0.001). CONCLUSION: Treatment of BAA remains in a trade-off between favorable clinical outcome and complete or near-complete occlusion depending on the treatment modality selected. Careful selection of cases and judicial discussion between open surgical and endovascular team is warranted for treatment optimization.

Diagnostic and Neurological Overview of Brain Tuberculomas: A Review of Literature.

Tuberculosis is a disease caused by a bacteria named Mycobacterium tuberculosis (M. tb). It is estimated by World Health Organization (WHO) that nearly a quarter of the world's population is infected. Tuberculoma of the brain is one of the most severe extrapulmonary forms that affects patients younger than 40 years of age. Brain parenchymal tuberculoma develops in nearly one of 300 non-treated cases of pulmonary tuberculosis cases. In endemic regions, tuberculomas account for as many as 50% of all intracranial masses. Tuberculoma results in a hematogenous spread of M. tb from an extracranial source. Tuberculomas can mimic a variety of diseases and can present themselves in a subacute or chronic course, from asymptomatic to severe intracranial hypertension. Diagnosis is based on computed tomography (CT) scan and magnetic resonance imaging (MRI) studies with a similar ring-enhancing lesion. Treatment is primarily medical, and the duration for brain tuberculoma can vary from six to 36 months. In certain cases, surgery is recommended.

Immunoglobulin G4-related disease of the cavernous sinus with orbit invasion - A case report.

BACKGROUND: Immunoglobulin G4-related disease (IgG4-RD) is a rare systemic disease of unknown etiology. It is characterized by tissue infiltration caused by IgG4 plasma cells and sclerosing inflammation of various body organs. At present, there are very few reported cases of IgG4-RD invasion of cavernous sinus and the orbit. CASE DESCRIPTION: A 56-year-old female with a history of rheumatoid arthritis was presented with a gradual onset of right oculomotor, abducens, and trigeminal nerve deficits. Four weeks after the onset of symptoms, the patient developed gradual visual deficit. Following this, a trial of steroids was administered to the patient. However, the treatment did not work as expected and patient's condition worsened. She progressed on to suffer complete visual loss in the right eye. Extensive work-up conducted on her turned out to be nondiagnostic. After this, the patient was referred to us for our evaluation. Neuroimaging revealed a right-sided cavernous sinus and orbital apex lesion. Given the lack of diagnosis and response to steroid treatment, we recommended surgical intervention and performed a modified pterional and pretemporal approach with extradural anterior clinoidectomy and transcavernous approach. We performed a lesion biopsy and cavernous sinus decompression, which helped in the partial recovery of visual function. The pathology report was consistent with IgG4-RD. CONCLUSION: IgG4-RD is a rare disease that occurs even less in combination with cavernous sinus and orbit invasion. The rarity of the disease and the diverse presentation of symptoms have sometimes caused delayed diagnosis and intervention. Patients who failed to respond to conservative management and patients in the fibrotic stage of the disease without other organ involvement may benefit from surgical intervention if amenable. Early suspicion, diagnosis, and intervention can facilitate better prognosis.

The use of exoscope combined with tubular retractor system for minimally invasive transsulcal resection of an ventricular atrium atypical choroid plexus papilloma: Three-dimensional operative video.

BACKGROUND: Choroid plexus papilloma represents 1-4% of pediatric brain tumors, mostly located in the ventricular atrium.[1] Intraventricular tumors represent a challenge due to the poor visualization of the surgical field and damage to surrounding structures.[2] Use of tubular retraction reduces cerebrovascular trauma to the surrounding parenchyma by distributing pressure uniformly, allowing less invasive corticotomy, and more stability on surgical corridors that allow the surgeon to use both hands and external visualization devices.[2-5]. CASE DESCRIPTION: We present the case of a 3-year-old boy with progressive headache, vomiting, and loss of control in the left hand for 3 months, with a history of ventricular shunt placement for acute obstructive hydrocephalus. The MRI revealed large lobulated lesion, which was hypointense on T1, hyperintense on T2, marked enhancement on T1 C+ (Gd) within the atrium of the right lateral ventricle, and spectroscopy with a peak of choline. Written consent for the use of photos and videos on this work was obtained from the patient's mother. A high-definition two-dimensional exoscope (VITOM® Karl Storz, Tuttlingen) was used during the surgical approach and throughout tumor removal, which was aided by ViewSite Brain Access System (VBAS®; Vycor Medical Inc.).[3] We performed a transparietal minimally invasive transsulcal parafascicular approach through the Frazier point for direct access to the ventricular atrium. Histological examination confirmed atypical choroid plexus papilloma. Postoperative imaging shows no residual tumor. The postoperative course was satisfactory with improvement of the headache and control of the left hand, leading to discharge home 1 week after surgery. CONCLUSION: The tubular transparietal minimally invasive approach obviates the need for traditional approaches to the atrium. This technique is safe and effective for the treatment of intraventricular and periventricular lesions, thus making this challenging target in more accessible to neurosurgeons, avoiding structure damage and any associated morbidity or mortality.

Epilepsy and Deep Brain Stimulation of Anterior Thalamic Nucleus.

Presently, at least 60 million people are suffering from epilepsy worldwide. Although multiple pharmacological options for treatment exist, about 30% to 40% of these patients are estimated to have drug-resistant epilepsy (DRE), which is associated with severe disability and morbidity. The surgical treatment options are restricted to either open surgical procedures or laser ablations. When a resective option is not favorable, then neuromodulation options such as vagal nerve stimulation and deep brain stimulation are considered. A relatively recent and more commonly used clinical application is the deep brain stimulation (DBS) of the anterior thalamic nucleus, FDA approval for which was obtained in 2018. Furthermore, new technological advances in DBS technology are expected to positively impact the treatment options of these patients.

Review of Atypical and Anaplastic Meningiomas: Classification, Molecular Biology, and Management.

Although the majority of meningiomas are slow-growing and benign, atypical and anaplastic meningiomas behave aggressively with a penchant for recurrence. Standard of care includes surgical resection followed by adjuvant radiation in anaplastic and partially resected atypical meningiomas; however, the role of adjuvant radiation for incompletely resected atypical meningiomas remains debated. Despite maximum treatment, atypical, and anaplastic meningiomas have a strong proclivity for recurrence. Accumulating mutations over time, recurrent tumors behave more aggressively and often become refractory or no longer amenable to further surgical resection or radiation. Chemotherapy and other medical therapies are available as salvage treatment once standard options are exhausted; however, efficacy of these agents remains limited. This review discusses the risk factors, classification, and molecular biology of meningiomas as well as the current management strategies, novel therapeutic approaches, and future directions for managing atypical and anaplastic meningiomas.

Current Surgical Options for Moyamoya Disease.

Moyamoya disease (MMD) is a cerebrovascular disease of unknown etiology characterized by stenotic and occlusive arterial changes of the anterior circulation, with subsequent proliferative development of arterial collateralization. In spite of there being limited understanding of the clear etiology of MMD, surgical revascularization for MMD is considered the standard treatment to prevent further stroke. While the use of surgical revascularization to prevent future hemorrhagic stroke in MMD is still controversial, it is considered effective in the case of ischemic stroke. This article presents a review of the current surgical management of MMD based on an analysis of the most recent data from peer-reviewed articles and opinion based on personal experience with surgical revascularization in the treatment of MMD.

The anterior incisural width as a preoperative indicator for intradural space evaluation: An anatomical investigation.

BACKGROUND: The opticocarotid triangle (OCT) and the carotico-oculomotor triangle (COT) are two anatomical triangles used in accessing the interpeduncular region. Our objective is to evaluate if the anterior incisural width (AIW) is an indicator to predict the intraoperative exposure through both triangles. METHODS: Twenty sides of 10 cadaveric heads were dissected and analyzed. The heads were divided into the following: Group A - narrow anterior incisura and Group B - wide anterior incisura - using 26.6 mm as a cutoff distance of the AIW. Subsequently, the area of the COT and the OCT in the transsylvian approach was measured, along with the maximum widths through the two trajectories in modified superior transcavernous approach. RESULTS: The COT in the wide group was shown to have a significantly larger area compared with the COT in the narrow group (38.4 ± 12.64 vs. 58.3 ± 15.72 mm, P < 0.01). No difference between the two groups was reported in terms of the area of the OCT (50.9 ± 19.22 mm vs. 63.5 ± 15.53 mm, P = 0.20), the maximum width of the OCT (6.6 ± 1.89 vs. 6.5 ± 1.38 mm, P = 1.00), or the maximum width of the COT (11.7 ± 2.06 vs. 12.2 ± 2.32 mm, P = 0.50). Clinical cases were included. CONCLUSION: An AIW <26.6 mm is an unfavorable factor related to a limited COT area in a transsylvian approach for pathologies at the interpeduncular fossa. Preoperative identification and measurement of a narrow AIW can suggest the need to add a transcavernous approach.

Combined petrosal approach for resection of petroclival chondrosarcoma: Microsurgical 2-D video.

BACKGROUND: Petroclival lesions pose a significant neurosurgical challenge due to involvement or close proximity to important neurovascular structures. Chondrosarcomas are rare lesions that can affect these areas. CASE DESCRIPTION: A 24-year-old male with 3 months history of poor coordination, imbalance, left-sided face hypoesthesia, facial palsy House-Brackmann Grade 2, and 6th cranial nerve palsy with diplopia. Hearing was preserved. Preoperative images showed a 5.5 cm multilobulated enhancing extra-axial mass centered in the left petroclival region with extension into middle and posterior fossa causing severe (Stage 3) brainstem compression.[1] After a lengthy discussion of treatment options, the patient consented for the procedure. We performed a presigmoid retrolabyrinthine combined petrosal approach. We used cranial nerves monitoring (VII, VIII, IX, X, XI, XII), frameless stereotaxy, and a lumbar drain. Due to the tumor size and location (petroclival region with extension into the posterior and middle cranial fossa), we chose this approach to achieve a maximal safe resection of the tumor and preserve hearing. Alternative approaches of use are expanded middle fossa with transcavernous extension or expanded endonasal approach. The selected approach achieved wide exposure of the tumor which was highly vascular. The tumor was carefully dissected off the brainstem, cranial nerves (IV, V, VI, VII, VIII), and basilar artery trunk. A gross total resection was achieved (Multimedia 1). The patient did well after surgery and was extubated on postoperative day (POD) 1 and the lumbar drain removed on POD 5. Pathology reported low-grade chondrosarcoma (WHO grade I). At 3 months follow-up, the patient improved neurologically, including facial nerve weakness (House-Brackmann Grade 1) except for his left 6th cranial nerve palsy which mildly improved. CONCLUSION: Petroclival chondrosarcomas are rare tumors that are usually treated with surgical resection followed by stereotactic radiosurgery. The tumor size, location, and extension dictate approach selection. For lesions involving the petroclival region with extension into the middle fossa and posterior fossa, the combined petrosal approach is reasonable.