Complications of Endovascular and Open Aneurysm Surgery in the Era of Flow Diversion.

The techniques used for treatment of intracranial aneurysms have progressed dramatically over the decades. The introduction of modern endovascular techniques and the continued refinement of progressively less invasive neurosurgical approaches have contributed to steadily improving clinical outcomes. Moreover, innovations such as flow-diverting stents have achieved dramatic success and have gained rapid widespread adoption. Particularly in lesions for which the application of conventional treatment techniques is difficult, flow diversion technology has revolutionized aneurysm management. This review provides a discussion on the morbidity and mortality encountered in the treatment of intracranial aneurysms in the modern era. Common adverse events faced in the management of these lesions with open surgery and various endovascular techniques are highlighted.

Spheno-orbital juvenile psammomatoid ossifying fibroma: a case report and literature review.

Ossifying fibroma (OF) is an uncommon benign fibro-osseous lesion. Based on its clinical, morphological, and radiological features, OF is further divided into cemento-ossifying fibroma (COF), juvenile psammomatoid ossifying fibroma (JPOF), and juvenile trabecular ossifying fibroma (JTOF). JPOF rarely involves the cranial base, with limited reports published on spheno-orbital JPOF. In this paper, we report a case of JPOF of the greater wing of the sphenoid bone and lateral orbital wall in an 11-year-old child and show a surgical video. Although rare, JPOF should be considered in the differential diagnosis of fibro-osseous lesions of the spheno-orbital region.

Rosette-Forming Glioneural tumor of the fourth ventricle: A case report and literature review.

Rosette-forming glioneural tumors (RGNTs) are rare. Here, we report a case of RGNT of the fourth ventricle in an 18-year-old female. The patient presented with a 4-month history of headache and dizziness. Neurological examination showed papilledema, impaired tandem gait, and right-sided dysmetria. Radiological images showed a posterior fossa lesion in the fourth ventricle with hydrocephalus. An emergent ventriculostomy was performed followed by gross total surgical resection of the lesion. Histopathological examination confirmed the diagnosis of RGNT. The patient developed posterior fossa syndrome postoperatively which improved on follow-up. Although rare, RGNT should be considered in the differential diagnoses of posterior fossa lesions in young patients. Given its benign course, surgical resection remains the treatment of choice.

Nocardial clival osteomyelitis secondary to sphenoid sinusitis: an atypical skull base infection.

Clival osteomyelitis is a life-threatening complication of untreated malignant otitis externa or paranasal sinus infection. Although various pathogens have been implicated, to our knowledge, primary nocardial clival osteomyelitis has never been reported. We describe a 74-year-old woman who presented with headaches, abducens and hypoglossal nerve palsies, facial numbness, photophobia, and neck stiffness. Imaging revealed a heterogeneous mass within the sphenoid sinus with clival extension. The lesion was extirpated via a binostril endoscopic endonasal transsphenoidal approach. Histopathological and microbiological examination revealed a nocardial source. Clival osteomyelitis associated with sphenoid sinusitis should be included in the differential diagnosis of progressive skull base lesions in the setting of an underlying infection. Early recognition and intervention with antibiotics and surgical debridement is essential in the management of this rare entity.

Cerebral venous sinus thrombosis after vestibular schwannoma surgery: a call for evidence-based management guidelines.

OBJECTIVE Postoperative cerebral venous sinus thrombosis (CVST) is an uncommon complication of posterior fossa surgery. The true incidence of and optimal management strategy for this entity are largely unknown. Herein, the authors report their institutional incidence and management experience of postoperative CVST after vestibular schwannoma surgery. METHODS The authors undertook a retrospective review of all vestibular schwannoma cases that had been treated with microsurgical resection at a single institution from December 2011 to September 2017. Patient and tumor characteristics, risk factors, length of stay, surgical approaches, sinus characteristics, CVST management, complications, and follow-up were analyzed. RESULTS A total of 116 patients underwent resection of vestibular schwannoma. The incidence of postoperative CVST was 6.0% (7 patients). All 7 patients developed lateral CVST ipsilateral to the lesion. Four cases occurred after translabyrinthine approaches, 3 occurred after retrosigmoid approaches, and none occurred following middle cranial fossa approaches. Patients were managed with anticoagulation or antiplatelet therapy. Although patients were generally asymptomatic, one patient experienced intraparenchymal hemorrhage, epidural hemorrhage, and obstructive hydrocephalus, likely as a result of the anticoagulation therapy. However, all 7 patients had a modified Rankin scale score of 1 at the last follow-up. CONCLUSIONS Postoperative CVST is an infrequent complication, with an incidence of 6.0% among 116 patients who had undergone vestibular schwannoma surgery at one institution. Moreover, the management of postoperative CVST with anticoagulation therapy poses a serious dilemma to neurosurgeons. Given the paucity of reports in the literature and the low incidence of CVST, additional studies are needed to better understand the cause of thrombus formation and help to establish evidence-based guidelines for CVST management and prevention.

Middle fossa approach for resection of vestibular schwannoma.

BACKGROUND: Surgical approaches for removal of vestibular schwannoma are done through retrosigmoid, translabyrinthine, or middle fossa approaches, depending on the tumor size, preoperative hearing status, surgical team experience, and patient preference. The middle fossa approach (MFA) for the vestibular schwannoma (VS) route preserves hearing and can be done with minimal morbidity and mortality. METHOD: The authors discuss the surgical anatomy of the middle fossa, internal auditory canal localization techniques, MFA indications and the procedure for VS removal, and outcome. CONCLUSION: Unlike otolaryngologists, who use the MFA to treat various pathological processes that involve the inner or middle ear, many neurosurgeons are unfamiliar with the MFA. Nevertheless, learning the technical nuances of the MFA adds to the neurosurgeon's armamentarium, especially for treatment of small intracanalicular VSs in young patients who wish to preserve hearing.

Neurosurgical Assessment of Metrics Including Judgment and Dexterity Using the Virtual Reality Simulator NeuroTouch (NAJD Metrics).

Advances in computer-based technology has created a significant opportunity for implementing new training paradigms in neurosurgery focused on improving skill acquisition, enhancing procedural outcome, and surgical skills assessment. NeuroTouch is a computer-based virtual reality system that can generate output data known as metrics from operator performance during simulated brain tumor resection. These measures of quantitative assessment are used to track and compare psychomotor performance during simulated operative procedures. Data output from the NeuroTouch system is recorded in a comma-separated values file. Data mining from this file and subsequent metrics development requires the use of sophisticated software and engineering expertise. In this article, we introduce a system to extract a series of new metrics using the same data file using Excel software. Based on the data contained in the NeuroTouch comma-separated values file, 13 novel NeuroTouch metrics were developed and classified. Tier 1 metrics include blood loss, tumor percentage resected, and total simulated normal brain volume removed. Tier 2 metrics include total instrument tip path length, maximum force applied, sum of forces utilized, and average forces utilized by the simulated ultrasonic aspirator and suction instrument along with pedal activation frequency of the ultrasonic aspirator. Advanced tier 2 metrics include instrument tips average separation distance, efficiency index, ultrasonic aspirator path length index, coordination index, and ultrasonic aspirator bimanual forces ratio. This system of data extraction provides researchers expedited access for analyzing the data files available for NeuroTouch platform to assess the multiple psychomotor and cognitive neurosurgical skills involved in complex surgical procedures.

A Prospective Comparison Between Soft Tissue Dissection Techniques in Pterional Craniotomy: Functional, Radiological, and Aesthetic Outcomes.

BACKGROUND AND OBJECTIVES: Given the complex anatomy of the operative region and individual surgeon preferences, some techniques for soft tissue dissection before pterional craniotomy have gained more popularity than others. This prospective study used subjective and objective measurements to compare the functional, radiological, and aesthetic outcomes of 3 such dissection techniques. METHODS: This multicenter prospective cohort study included all patients who underwent elective pterional craniotomy between 2018 and 2020 at 3 centers in Riyadh, Saudi Arabia. All patients underwent 1 of 3 soft tissue dissection techniques: myocutaneous flap, interfascial, and subfascial dissection techniques. Clinical and radiological assessments were performed upon discharge and at the 3- and 6-month follow-ups. RESULTS: We included 78 patients, with a mean age of 44.9 ± 16.3 years. Myocutaneous flap, interfascial, and subfascial dissections were performed in 34 (43%), 24 (30%), and 20 patients (25%), respectively. The myocutaneous flap method had the shortest opening ( P = .001) and closure ( P = .005) times; tenderness was more evident in this group than in the others ( P = .05). The frontalis muscle was most affected in the interfascial dissection group ( P = .05). The frontalis nerve function was similar in all groups after 6 months ( P = .54). The incidence of temporomandibular joint dysfunction was highest in the myocutaneous flap group (29%). Decreased temporalis muscle thickness at the 6-month postoperative follow-up was most severe in the subfascial dissection group (12.6%), followed by the myocutaneous flap (11.9%) and interfascial dissection (9.9%) groups, with no significant difference ( P = .85). Temporal hollowing was more prominent in the myocutaneous flap group ( P = .03). Cosmetic satisfaction was highest in the interfascial dissection group, with no significant difference ( P = .4). CONCLUSION: This study provides important information for neurosurgeons in weighing the benefits and risks of each technique for their patients.

"Brain Biopsy Revolution: Unveiling the Core Syringe Technique with Clinical Insights".

OBJECTIVES: Obtaining a definitive pathological diagnosis from brain tissue sampling was challenging due to the small, non-representative sample. This study introduced a novel syringe technique for brain biopsy aimed at enhancing diagnostic accuracy by obtaining core tissue samples that better represent the targeted tissue. METHODS: The ten patients with atypical brain lesions underwent the syringe biopsy. After meticulous preoperative planning with neuronavigation, a minimally invasive approach was used: a 3 cm skin incision and a 14 mm burr hole were created. A modified 3-cc syringe was used to create negative pressure and cannulate the brain tissue. The desired sample size (24 cm³) was obtained by controlling the syringe depth and withdrawal. Medical records were reviewed to assess sample analysis results and any complications RESULTS: The syringe technique successfully yielded adequate tissue samples in 9 out of 10 patients. In one case, the desired tissue could not be retrieved and required a microsurgical approach for removal. In all ten cases, a correct diagnosis was made without significant complications. CONCLUSION: The preliminary findings suggest that the syringe technique is both safe and effective for obtaining substantial volumes of brain tissue, facilitating accurate pathological evaluation in cases of complex neurological disorders.

Endoscopic Endonasal Resection of a Cavernous Malformation of the Third Ventricle: Case Report and Literature Review.

BACKGROUND: Suprasellar and third ventricle cavernous malformations (CMs) are uncommon. Conventional approaches such as interhemispheric and translamina terminalis approaches are often used to resect these lesions. Here we demonstrate the use of the endoscopic endonasal approach for a third ventricle CM. CASE DESCRIPTION: A 31-year-old man presented with progressive symptoms of headache and visual disturbance as well as short-term memory deficit over a 6-month period. Neurologic examination revealed bitemporal hemianopsia. Radiologic images showed a suprasellar lesion extending into the third ventricle as well as obstructive hydrocephalus. The patient was operated on using an endoscopic endonasal approach and histopathology revealed a diagnosis of CM. Transient diabetes insipidus and adrenal insufficiency were reported postoperatively. CONCLUSION: This report demonstrates safe resection of a third ventricle CM via the endonasal route.

Neurenteric cyst of the dorsal craniocervical junction in an adult: A case report and operative video.

Background: Neurenteric cysts (NCs) are rarely located in the dorsal craniocervical junction (CCJ). Case Description: Here, we present a case and show the surgical video of a 24-year-old man with a history of neck pain, progressive hemiparesis, and difficulty swallowing. Radiological images revealed an intradural extramedullary lesion at the dorsal CCJ. Posterior approach with C1-C2 laminectomy for resection of the lesion was performed with significant improvement in symptoms postoperatively. Histopathological examination confirmed the diagnosis of NC. Conclusion: This case demonstrates a rare location of a NC in an adult patient. Complete excision of the cyst wall and its content is the recommended treatment option.

Bibliometric analysis of the top 100 most-cited articles on astrocytoma.

BACKGROUND: Citation analysis reflects the scientific recognition and influential performance of a published article within its field. We aim to identify the top 100 most-cited articles on astrocytoma using this bibliometric analysis method. METHODS: In May 2020, we performed a thorough search in the Scopus database using the word "Astrocytoma." The top 100 most-cited articles were arranged based on citation count in descending order. The resultant articles were then analyzed with an assessment of pertinent factors. RESULTS: The most-cited articles on astrocytoma had been cited 23,720 times. The top-cited article received a total of 682 citations, with an average of 34.1 citations annually. The list comprised eight clinical trials, in which the highest cited article received 625 citations. Articles were published from 1975 to 2015 with the 1995-2005 era as the most prolific period. Neuropathology studies were the most studied category, followed by clinical studies. The United States of America was the most significant contributor, with 49 published articles. The University of California San Francisco was the most contributing institution by producing 11 articles. Articles were published in 32 different journals led by the Cancer Research Journal, with a total of 12 publications. Approximately 160 authors contributed to the list in which Scheithauer, B.W. contributed the most with a total of eight articles. CONCLUSION: This report clustered the most impactful articles on astrocytoma. It serves as an adequate tool to identify publication trends and helps in achieving evidence-based clinical practice.

Bibliometric Analysis of the Top 100 Most Cited Articles on Cerebral Vasospasm.

OBJECTIVE: Bibliometric analysis reflects the scientific recognition and influential performance of a published article within its field. Our aim is to identify and analyze the top 100 most-cited articles on cerebral vasospasm. METHODS: A title-specific search was carried out using the Scopus database. The top 100 cited articles including the keywords "Cerebral Vasospasm" AND "Vasospasm" were retrieved and stratified in a descending order: title, authors, institution, publishing journal, country of origin, year of publication, and topic of each article were studied. RESULTS: The top 100 articles have an accumulative citation count of 20,972, with 209 average citations per article. Publication dates ranged from 1968 to 2012, with the most productive years between 1998 and 2005. Clinical studies are the most frequent category, followed by pathophysiology. The list includes 7 clinical trials, which received accumulative citations of 1525. The top cited article had received 2109 citations, with 52.7 citations per year. The top 100 articles were published across 14 countries, with most originating from the United States. The lead research institution was the University of Alberta. The most used journal was Journal of Neurosurgery. CONCLUSIONS: Bibliometric analysis has garnered major interest in recent years. It shows the publication trends, knowledge evolution, and evidence-based practice throughout the years. The collection of highly cited articles may assist physicians in gaining a better understanding of the nature of cerebral vasospasm and optimize their clinical practice.

How Reliable Is the Intraoperative Computed Tomography Angiography in Assessing Complete Surgical Resection of Cerebral Arteriovenous Malformations?

BACKGROUND: Digital subtraction angiography (DSA) is still considered the gold standard test to evaluate arteriovenous malformation's (AVM) residual after microsurgical resection. OBJECTIVE: To evaluate the safety and reliability of intraoperative computed tomography angiography (iCTA) as an immediate method of evaluating the surgical results of AVM resection. METHODS: We performed a retrospective review for all cases of cerebral AVMs at our institute from January 2015 to April 2020 who underwent surgical resection of cerebral AVM and had iCTA. All included patients underwent a postoperative DSA, and the results were compared with iCTA. RESULTS: Twenty-eight cases were included. All cases showed complete resection (100%) in the iCTA, and the results were consistent with the postoperative DSA results. The sensitivity of iCTA was 100%. The added operative time ranged from 25 to 30 min. There were no complications related to the use of iCTA. CONCLUSION: Intraoperative assessment of AVMs surgical results with an iCTA is safe and reliable. The sensitivity of iCTA following AVM resection merits further investigations.

A potential new brainstem reflex: The oculoglossal phenomenon.

BACKGROUND: A synchronized involuntary movement of the tongue to the same side as voluntary movements of the eyes, termed the oculoglossal phenomenon, has been observed. A description of the hypothesized pathway of this phenomenon could guide the development of a rapid clinical evaluation of the long segment of the brainstem and help facilitate further studies to establish a new reflex, if possible. The aim of this study is to describe and propose the simple concept of this pathway/phenomenon, the oculoglossal phenomenon. METHODS: This is an observational study. Of a newly observe brainstem phenomenon evaluated on a subject at the National Neuroscience Institute in king Fahad Medical City (KFMC), Riyadh, Saudi Arabia. After being observed incidentally in a single patient, 60 participants were tested between January and March 2020 to confirm the presence of the phenomenon. Each subject was instructed to protrude the tongue and then move their eyes horizontally to the side. If the tongue simultaneously and involuntarily moved to the same side as the eyes, the test was deemed confirmatory. A literature review was performed, and possible anatomical pathway was proposed. RESULTS: The oculoglossal reflex was present in most (50/60, 83.3%) of the subjects. Our proposed pathway begins at the frontal cortex, followed by a projection to the paramedian pontine reticular formation, then to the contralateral medial longitudinal fasciculus and bilaterally to the hypoglossal nuclei. CONCLUSION: An accurate description of this phenomenon could lead to additional studies and possibly establishing it as a legitimate reflex, thus conceivably adding a new tool in the neurological examination to evaluate the brainstem's integrity.

High-grade spheno-orbital meningioma in patients with systemic lupus erythematosus: Two case reports and literature review.

BACKGROUND: Spheno-orbital meningiomas (SOMs) are often benign. The association of meningioma and systemic lupus erythematosus (SLE) is rarely discussed in the literature. Here, we report two patients with high-grade, SOMs with a prolonged history of SLE and review the literature. CASE DESCRIPTION: The first case is a 52-year-old female patient with a 15-year history of SLE diagnosis who was referred to our center with a 1-year history of proptosis and excessive tearing of the left eye. This patient was operated for the left SOM with histopathological diagnosis of the World Health Organization (WHO) Grade III rhabdoid meningioma. The second case is a 36-year-old female patient with a 12-year history of SLE diagnosis who presented to our clinic with a 5-year-history of progressive right eye proptosis and occasional headaches. She was operated for the right SOM with histopathological diagnosis of the WHO Grade II chordoid meningioma. CONCLUSION: Rhabdoid and chordoid SOMs are uncommon and no previous report discussed their occurrence in patients with SLE. The association of high-grade meningiomas and SLE deserves further exploration.

Repeat Resection of a Cavernous Malformation of the Optic Nerve/Chiasm via a Frontotemporal Approach: 2-Dimensional Operative Video.

Cavernous malformations are benign vascular lesions that can arise throughout the central nervous system. The occurrence of a cavernous malformation within the optic nerve or chiasm, however, is extremely uncommon. The case described in this video involved a 36-yr-old woman who presented 3 mo after undergoing a left frontotemporal craniotomy for resection of an optic nerve cavernous malformation. She had initially presented to an outside hospital with vision loss, and the left optic nerve lesion was identified and resected. Although her vision had reportedly improved slightly postoperatively, she awoke 3 mo later with bilateral subjective blurriness and new visual field deficits. Magnetic resonance imaging revealed enlargement of the left optic apparatus hemorrhagic lesion, corresponding to residual cavernous malformation. Given the recurrence of hemorrhage and the associated visual symptoms, the patient underwent a redo left frontotemporal craniotomy for resection of the optic nerve and chiasmal lesion. Histopathologic evaluation revealed thick-walled vessels with focal intervening glial tissue, an absence of neoplastic cells, and hemorrhage, consistent with a cavernous malformation. The patient tolerated the procedure well. Postoperatively, she experienced immediate amelioration in her visual symptoms. She was discharged home on postoperative day 3, and her bitemporal visual field deficit continued to progressively improve through her last ophthalmologic appointment 14 mo after surgery. Postoperative and subsequent surveillance neuroimaging demonstrated complete resection of the cavernous malformation without evidence of recurrence. This case demonstrates the techniques utilized to ensure complete resection of the malformation in this very eloquent region. The patient provided consent for publication.

Bibliometric Analysis of Top 100 Most Cited Articles on Intraventricular Hemorrhage.

BACKGROUND: Intraventricular hemorrhage (IVH) is a rare cause of intracranial bleeding across all age groups, with dismal sequelae in most of the affected population. The reported data on IVH are numerous, with multiple levels of evidence. We performed a citation-based analysis to identify the most-cited reports on IVH. METHODS: A thorough search of the Scopus database was conducted using "intraventricular hemorrhage" as the search keyword. The 100 most cited studies were stratified in descending order. The reports were reviewed in-depth and categorized accordingly. Bibliometric parameters of interest were obtained for analysis. RESULTS: The most-cited studies had been published between 1927 and 2017. Most (n = 60) had been published between 1980 and 2000. The most-cited studies had received a total of 16,512 citations, with an average of 174 citations per report. Studies on pathogenesis were the most prolific, with 23 articles included. A total of 13 randomized controlled trials were identified. The top contributing country was the United States, with 67 reports. The leading institution was the Washington University School of Medicine in St. Louis, Missouri, with 11 studies. Pediatrics was the most active journal, with 20 studies. CONCLUSION: The present collection of highly cited studies can aid in the understanding of chronological trends and could serve as an efficient guide to delineate the reports involved in the evidence-based practice of the management of IVH.

Internal Auditory Canal Variability: Anatomic Variation Affects Cisternal Facial Nerve Visualization.

BACKGROUND: The internal auditory canal (IAC) is an important landmark during surgery for lesions of the cerebellopontine angle. There is significant variability in the position and orientation of the IAC radiographically, and the authors have noted differences in surgical exposure depending on the individual anatomy of the IAC. OBJECTIVE: To test the hypothesis that IAC position and orientation affects the surgical exposure of the IAC and facial nerve, especially when performing the translabyrinthine approach. METHODS: The authors retrospectively reviewed magnetic resonance imaging studies of 50 randomly selected patients with pathologically confirmed vestibular schwannomas. Measurements, including the anterior (APD) and posterior (PPD) petrous distances, the anterior (APA) and posterior (PPA) petro-auditory angles, and the internal auditory angle (IAA), were obtained to quantify the position and orientation of the IAC within the petrous temporal bone. RESULTS: The results quantitatively demonstrate tremendous variability of the position and orientation of the IAC in the petrous temporal bone. The measurement ranges were APD 10.2 to 26.1 mm, PPD 15.1 to 37.2 mm, APA 104 to 157°, PPA 30 to 96°, and IAA -5 to 40°. CONCLUSION: IAC variability can have a substantial effect on the surgical exposure of the IAC and facial and vestibulocochlear nerves. Specifically, a horizontally oriented IAC with a small IAA may have significant impact on visualization of the facial nerve within its cisternal segment with the translabyrinthine approach. The retrosigmoid approach is less affected with IAC variability in position and angle.

Outcomes of decompressive surgery for cavernous sinus meningiomas: long-term follow-up in 50 patients.

OBJECTIVE: Cavernous sinus meningiomas are complex tumors that offer a perpetual challenge to skull base surgeons. The senior author has employed a management strategy for these lesions aimed at maximizing tumor control while minimizing neurological morbidity. This approach emphasizes combining "safe" tumor resection and direct decompression of the roof and lateral wall of the cavernous sinus as well as the optic nerve. Here, the authors review their experience with the application of this technique for the management of cavernous sinus meningiomas over the past 15 years. METHODS: A retrospective analysis was performed for patients with cavernous sinus meningiomas treated over a 15-year period (2002-2017) with this approach. Patient outcomes, including cranial nerve function, tumor control, and surgical complications were recorded. RESULTS: The authors identified 50 patients who underwent subtotal resection via frontotemporal craniotomy concurrently with decompression of the cavernous sinus and ipsilateral optic nerve. Of these, 25 (50%) underwent adjuvant radiation to the remaining tumor within the cavernous sinus. Patients most commonly presented with a cranial nerve (CN) palsy involving CN III-VI (70%), a visual deficit (62%), headaches (52%), or proptosis (44%). Thirty-five patients had cranial nerve deficits preoperatively. In 52% of these cases, the neuropathy improved postoperatively; it remained stable in 46%; and it worsened in only 2%. Similarly, 97% of preoperative visual deficits either improved or were stable postoperatively. Notably, 12 new cranial nerve deficits occurred postoperatively in 10 patients. Of these, half were transient and ultimately resolved. Finally, radiographic recurrence was noted in 5 patients (10%), with a median time to recurrence of 4.6 years. CONCLUSIONS: The treatment of cavernous sinus meningiomas using surgical decompression with or without adjuvant radiation is an effective oncological strategy, achieving excellent tumor control rates with low risk of neurological morbidity.