Microsurgical Clip Ligation of a Large Anterior Communicating Artery Aneurysm Previously Treated With Woven Endobridge Device: 2-Dimensional Operative Video.

The Woven Endobridge (WEB) intrasaccular flow diversion device (Microvention, Inc.) is commonly used to treat both unruptured and ruptured wide-necked bifurcation aneurysms.1 Despite its relative safety and comparable rates of aneurysm occlusion, the device may compress over time resulting in aneurysm recurrence.2 In this video, we demonstrate the microsurgical retreatment of a large anterior communicating artery (ACoA) aneurysm previously treated with WEB. A 53-year-old patient with hypertension and current tobacco use presented with a ruptured ACoA aneurysm measuring 8.4 mm × 8 mm × 7 mm. She was urgently treated with a 9 mm × 5 mm WEB SL and made a full recovery. At 6 months, cerebral angiography showed a significant recurrence secondary to WEB compression. We considered both endovascular and microsurgical approaches; however, the anatomy was unfavorable for endovascular treatment.3 Although previous reports have documented clipping as a retreatment strategy, a minority of these aneurysms were ACoA aneurysms.4-7 The patient consented to the surgical procedure. This operative video illustrates the in vivo appearance of the WEB device and the surgical technique used to treat this unusual situation. The WEB device was firm and not as compressible as previously reported, but clipping was still possible.4,6 We highlight the use of temporary clipping, fenestrated clips, and intraoperative angiography in treatment. The aneurysm was occluded, and the patient remained without deficits. In summary, clip ligation can be an excellent option for ACoA aneurysms in the setting of WEB recurrence. The patient consented to this report; Institutional Review Board/ethics committee approval was not required.

A Cerebellar Tumor-to-Tumor Metastasis in a Patient With Von Hippel-Lindau Disease.

Tumor-to-tumor metastasis in the central nerve system is uncommon in our routine practice. Most reports include metastatic breast cancer into meningioma. Here we report a metastatic clear cell renal cell carcinoma (ccRCC) into a cerebellar hemangioblastoma in a patient with von Hippel-Lindau (VHL) disease. Imaging cannot distinguish metastatic ccRCC from primary cerebellar hemangioblastoma. Immuno-molecular studies are proven to be diagnostic. We also reviewed previously documented tumor-to-tumor metastasis of ccRCC to cerebellar hemangioblastoma in VHL disease. Lastly, we discussed potential mechanisms involved in the metastasis of ccRCC to hemangioblastoma in the cerebellum in patients with VHL.

Novel Superior Cerebellar Artery Aneurysm Coming from a Superior Cerebellar Artery-Posterior Cerebral Artery Anastomotic Branch.

A middle-aged patient presented with subarachnoid hemorrhage and was found to have a ruptured superior cerebellar artery (SCA) aneurysm arising from the origin of a rare anastomotic branch between the right SCA and right posterior cerebral artery (PCA). The aneurysm was secured by transradial coil embolization, and the patient made a good functional recovery. This case demonstrates an aneurysm arising from an anastomotic branch between the SCA and PCA, which may represent a remnant of a persistent primordial hindbrain channel. Although variations in basilar artery branches are common, aneurysms rarely can form at the site of seldom- seen anastomoses between the branches of the posterior circulation. The complex embryology of these vessels, which includes anastomoses and the involution of primitive arteries, may have contributed to the development of this aneurysm arising from an SCA-PCA anastomotic branch.

Early Surgery for Moyamoya Is Not Associated with Worse Outcomes: Analysis of a North American Adult Cohort.

BACKGROUND: Patients with symptomatic moyamoya disease (MMD) or moyamoya syndrome (MMS) are at high risk of recurrent stroke. Surgical revascularization with either direct or indirect superficial temporal artery to middle cerebral artery bypass is a well-accepted treatment. However, the optimal timing and surgical technique for adult patients with MMD or MMS remain unknown. METHODS: We performed a retrospective medical record review of patients who had undergone superficial temporal artery to middle cerebral artery bypass for MMD or MMS from January 1, 2017, to January 1, 2022. The data collected included demographics, comorbidities, complications, as well as angiographic, and clinical outcomes. Early surgery was defined as surgery performed ≤2 weeks of the last stroke and delayed surgery as surgery performed >2 weeks after the last stroke. In the statistical analysis, we compared early versus delayed surgery and direct versus indirect bypass. RESULTS: Nineteen patients had undergone bypass surgery on 24 hemispheres. Of the 24 cases, 10 were early and 14 were delayed. In addition, 17 were direct, and 7 were indirect. No statistically significant difference was found in total complications between the early (3 of 10; 30%) and delayed (3 of 14; 21%; P = 0.67) groups. Five complications occurred in the direct group (5 of 17; 29%) and one in the indirect group (1 of 7; 14%; P = 0.63). No mortalities related to surgery occurred. Angiographic follow-up showed more extensive revascularization after early direct bypass than after delayed indirect bypass. CONCLUSIONS: In our population of North American adults who had undergone surgical revascularization for MMD or MMS, early surgery within 2 weeks of the last stroke did not differ from delayed surgery in terms of complications or clinical outcomes. Early direct bypass showed more revascularization on angiography than did delayed indirect surgery.

Quamdiu? Time to proficiency in endoscope-assisted minimally invasive clot evacuation.

INTRODUCTION: Spontaneous intraparenchymal brain hemorrhages are a devastating disease associated with significant disability or death. Minimally invasive clot evacuation (MICE) techniques can reduce mortality. We reviewed our experience with learning endoscope-assisted MICE to determine whether adequate results could be obtained in less than 10 cases. METHODS: We performed a retrospective chart review of patients undergoing endoscope-assisted MICE at a single institution by a single surgeon from January 1, 2018 to January 1, 2023 using a neuro-endoscope, a commercial clot evacuation device, and frameless stereotaxis. Demographic data was collected along with surgical results and complications. Image analysis using software determined the degree of clot removal. Hospital length of stay and functional outcomes were assessed using the Glasgow Coma Scale score (GCS) and Glasgow Outcome Score (extended) (GOS-E). RESULTS: Eleven patients were identified: average age 60.82 years old, 64 % male, all had hypertension. There was a clear improvement in IPH evacuation over the series. By case #7, greater than 80 % of clot volume was evacuated consistently. All patients remained neurologically stable or improved following surgery. In long-term follow-up, four patients (36.4 %) had good outcomes (GOS-E ≥ 6) and 2 patients had fair outcomes (GOS-E = 4) (18 %). There were no surgical mortalities, re-hemorrhages, or infections. CONCLUSIONS: With an experience of less than 10 cases, it is possible to obtain results comparable to most published series of endoscope-assisted MICE. Benchmarks such as greater than 80 % volume removal, less than 15 mL residual, and 40 % good functional outcomes can be obtained.

Successful Endovascular Treatment of Delayed Spontaneous Intracranial Internal Carotid Artery Blowout Following Orbital Exenteration and Radiation.

Most head and neck cancers require aggressive surgical resection followed by external beam radiation therapy. The carotid artery can be injured by surgery or radiation resulting in a delayed "blowout." A patient who had undergone orbital exenteration for a lacrimal adenoid cystic carcinoma (ACC) followed by external beam radiation presented 16 years later with arterial bleeding from the orbit caused by "blowout" of the cavernous internal carotid artery (ICA). We review the literature on carotid blowout syndrome (CBS) and treatment. The patient was emergently transferred to a hybrid operating room and underwent a balloon occlusion test (BOT) and endovascular sacrifice of the ICA with no neurological deficits postoperatively. Emergent endovascular embolization is an effective treatment for an intracranial ICA blowout in this first reported case of a blowout through the orbit. Elevated radiation dose and lack of tissue coverage may put the cavernous ICA at risk for this delayed complication.

Successful endovascular removal of a chondroblastic osteosarcoma embolus within the left middle cerebral artery.

A 57-year-old woman with metastatic chondroblastic osteosarcoma developed sudden-onset right-sided weakness and aphasia. She was found to have an occluded left middle cerebral artery (M1 segment) and underwent endovascular stroke intervention with return to a normal neurological exam within 24 h. Histologic analysis of the embolus was consistent with chondroblastic osteosarcoma.

"Plugged" Anterior Inferior Cerebellar Artery Aneurysm Causing Facial Palsy, Hearing Loss, and Subarachnoid Hemorrhage Treated by a Translabyrinthine Approach.

Anterior inferior cerebellar artery (AICA) aneurysms are rare, less than 1%-2% of all intracranial aneurysms. Aneurysms of the distal AICA are even less common and can present with hearing loss and facial paralysis because of their relationship with the internal auditory canal (IAC). A 65-year-old male was followed for fluctuating left facial weakness and left-sided hearing loss for over a year. Serial magnetic resonance imaging (MRI) scans showed a mass near the left IAC, thought to be a vestibular schwannoma. Just prior to his next clinic visit, the patient deteriorated suddenly from a subarachnoid hemorrhage. Cerebral angiography revealed a 5.5 mm saccular aneurysm at the distal left AICA, which was clip ligated via a translabyrinthine (TL) approach. The patient had a good functional outcome (modified Rankin Scale [mRS] 1) after 30 days despite persistent left facial weakness. Stable obliteration of the aneurysm was demonstrated by cerebral angiography postoperatively. Distal AICA aneurysms are rare and can have a similar presentation to tumors in the cerebellar pontine angle. Because of the unique anatomy of the distal AICA, open clip ligation via a TL approach is an effective method to secure these aneurysms.

COVID-19: Initiating the Expansion of Telemedicine in Neurosurgery.

OBJECTIVE: As COVID-19 spreads around the world, so does telemedicine across many medical specialties including neurosurgery. Given the unique patient population in neurosurgery, arising opportunities for integration and expansion of telemedicine into neurosurgery practice come with challenges for both the patient and the provider. METHODS: A literature review has been performed, and a survey has been sent out to neurosurgery providers in Texas to determine if providers are satisfied with the current state of telemedicine in their clinical practice. RESULTS: Patients who live far away from a medical center have cited increased convenience when routine postoperative visits have been converted to telemedicine. For providers, challenges have arisen in performing physical exams, especially when performing detailed neurological exams in the diagnosis of a spine disorder. Survey results of neurosurgery providers have revealed mixed opinions since the initiation of telemedicine. CONCLUSION: Although it is unclear what role telemedicine will have after the social distancing restrictions are lifted, many providers surveyed have expressed interest in keeping telemedicine in their clinical practice.

Off-Label Application of Pipeline Embolization Device for Intracranial Aneurysms.

PURPOSE: The Pipeline embolization device (PED) is approved in the USA for treating giant and large aneurysms arising from the petrous to superior hypophyseal segments of the internal carotid artery in patients older than 21 years of age. This study investigates off-label PED results in a large cohort. MATERIALS AND METHODS: Retrospective, single-center review of all patients who had off-label PED surgery. RESULTS: Sixty-two aneurysms (48 patients) underwent off-label PED treatment from 2012- 2017. There were 44 females and four males (age 21 to 75 years; mean/median, 54.3/55.0 years). The most common presenting symptom was headache (47/62, 75.8%). All aneurysms were in the anterior circulation. Aneurysm size ranged from 1.4 to 25.0 mm (mean/median, 7.6/6.9 mm). Fifty-two aneurysms had post-operative imaging with total/near-complete occlusion of 84.6% (44/52). Aneurysm-based operative near-term complication rate was 9.7% while there were no permanent complications. For aneurysms and headache, 86.7% improved/resolved after embo-surgery, and were four times more likely to have a better clinical outcome (resolved or improved symptoms) after surgery (odds ratio [OR], 4.333; P=0.0325). Left-sided aneurysms had a higher occlusion rate (OR, 20; P=0.0073). Hypertension (OR, 4.2; P=0.0332) and smoking (OR, 7; P=0.0155) were more prone towards aneurysm occlusion. Patients without a family history were 14 times more likely to have favorable imaging outcome (P=0.0405). There is no difference of occlusion rates between untreated and previously treated aneurysms (P=0.6894). Overall, occlusion rate decreased by 14% with an increase of aneurysm size by 1 mm (P=0.0283). CONCLUSION: For anterior circulation aneurysms, the off-label application of PED is as effective and safe as reported for on-label intracranial aneurysms.

Glioblastoma multiforme presenting as cryptogenic intracerebral hemorrhage.

We report a case of glioblastoma multiforme that presented as a large, spontaneous intracerebral hemorrhage (ICH). A 52-year-old woman developed headaches associated with photophobia and nausea. Computed tomography scan revealed a large ICH in the right temporal lobe. Further imaging, including magnetic resonance imaging and catheter-based arteriography, did not demonstrate an underlying lesion. She had 2-month follow-up imaging that was consistent with resolution of her hematoma and, again, no evidence of an associated mass. Six months after the initial ICH, she presented with worsening headaches. Magnetic resonance imaging of her brain at that time clearly demonstrated a large enhancing mass in the area of prior hemorrhage. Following tumor resection, histological diagnosis indicated glioblastoma multiforme. This case highlights the benefit of neurosurgical follow-up for patients with cryptogenic ICH and maintaining a high index of suspicion for brain tumor.

Endovascular treatment of a large ruptured middle cerebral artery bifurcation aneurysm in a 5-week-old infant: case report.

Ruptured intracranial aneurysms are extremely rare in infants. The optimal treatment strategy is not well established. Both microsurgical and endovascular techniques and strategies have been tried, and in the literature there is a significant variability in outcome. The authors report the presentation and successful endovascular treatment of a large, ruptured, middle cerebral artery bifurcation aneurysm in a 5-week-old girl, one of only a few reported in the literature. Clinical and radiological findings at follow-up are also presented. The authors then review the literature on aneurysmal subarachnoid hemorrhage in infants, with particular regard to outcome after either endovascular or open surgical management. They also provide recommendations for follow-up in pediatric patients whose intracranial aneurysms have been treated with coil embolization.

Endovascular Stroke Therapy Results Improve over Time: The 'Learning Curve' at a New Comprehensive Stoke Center.

BACKGROUND: The requirements for a comprehensive stroke center (CSC) include the capability to perform endovascular stroke therapy (EST). EST is a complex process requiring early identification of appropriate patients and effective delivery of intervention. In order to provide prompt intervention for stroke, CSCs have been established away from large academic centers in community-based hospitals. We hypothesized that quantifiable improvements would occur during the first 2 years of a community-based CSC as the processes and personnel evolved. We report the results over time of EST at a new community-based CSC. METHODS: We have retrospectively analyzed demographic data and outcome metrics of EST from the initiation phase of a new community-based CSC. Data was divided into year 1 and year 2. Statistical analysis (Student's t test and Fisher's exact test) was performed to compare the patient population and outcomes across the two time periods. Outcome variables included the thrombolysis in cerebral infarction (TICI) score, a change in the NIH stroke scale score and the modified Rankin Scale (mRS) score. Analysis of variance (ANOVA) was used to statistically analyze the relationship between population variables and outcome. Computed tomography (CT) angiography and CT perfusion analysis were used to select patients for EST. Approximately half of the patients undergoing EST were excluded from receiving intravenous recombinant tissue plasminogen activator (IV rt-PA) by standard criteria, while the other half showed no sign of improvement following 1 h of IV rt-PA treatment. Mechanical thrombolysis with a stentriever was performed in the majority of cases with or without intra-arterial medication. The majority of treated occlusions were in the middle cerebral artery. RESULTS: A total of 18 patients underwent EST during year 1 and year 2. A statistically significant increase in good outcomes (mRS score ≤2 at discharge) was seen from year 1 to year 2 (p = 0.05). There were trends towards faster interventions, decreased complications and mortality as well as an improved TICI score from year 1 to year 2. With ANOVA, mortality was statistically correlated with age (p = 0.06), while decreases in the NIH stroke scale (NIHSS) score following EST correlated with decreased mortality (p = 0.01). A higher TICI score was significantly associated with a decreased NIHSS score following EST (p = 0.01). CONCLUSIONS: At a new community-based CSC, improved outcome occurred from year 1 to year 2, and trends towards decreased mortality, fewer complications, and improved revascularization were observed. Furthermore, the data shows that improvement in NIHSS score after EST is associated with decreased mortality following stroke in this setting, implying a net benefit.

Cellular solitary fibrous tumor (hemangiopericytoma) with anaplasia at cerebellopontine angle--a case report.

Cellular solitary fibrous tumor is currently considered a synonym for hemangiopericytoma, as it became increasingly clear that the morphological and immunohistochemical features that separate these two entities have become tenuous, and evidence for a unifying concept has emerged. Furthermore, as no evidence of pericytic differentiation is given in most cases of hemangiopericytoma, this diagnostic term is waning in popularity. We present here a case of cellular solitary fibrous tumor in a 22-year-old man. Neuroimaging revealed a right cerebellopontine angle tumor. Most of the tumor was cellular although some less cellular areas were seen. Sinusoidally dilated large vessels, including staghorn type, were seen. Nuclear pleomorphism and increased mitotic activity (5 mitosis/10 high power field) were regarded as evidence of anaplasia. Diffuse CD34 immunoreactivity and focal positivity for Factor XIIIa were seen in the tumor, which was negative for EMA and S100. The tumor also displayed rich reticulin network. Solitary fibrous tumor at cerebellopontine angle is rare, and 20 such cases (five reported as hemangiopericytoma) have been reported in the English literature.

Posterior fossa neurenteric cysts can expand rapidly: case report.

Neurenteric cysts are considered congenital lesions that may slowly expand over time. Although more commonly found in the spinal canal, they may be found intracranially, particularly in the posterior fossa. Here, we present an unusual case of a large, rapidly expanding histologically confirmed posterior fossa neurenteric cyst in a 53-year-old woman, who presented with quadriparesis. Computed tomography imaging done ~1.5 years before admission failed to demonstrate any obvious abnormality; however, the lesion had grown to 4 cm in maximal dimension at presentation with significant mass effect. The lesion was resected microsurgically using a retrosigmoid approach. The patient improved postoperatively and was neurologically intact at last follow-up. We could find no other documented case of marked, rapid expansion of a neurenteric cyst in the literature. We conclude that, although neurenteric cysts are thought to be congenital, they can undergo rapid expansion even in adults. The mechanism of expansion is unknown but may involve increased secretion, hemorrhage, or inflammation. We discuss the surgical management and review the literature in view of this surprising finding.

Genomic analysis of ischemic preconditioning in adult rat hippocampal slice cultures.

Understanding endogenous mechanisms of neuroprotection may have important clinical applications. It is well established that brain tissue becomes more resistant to ischemic injury following a sublethal ischemic insult. This process, called ischemic preconditioning (IPC), can be induced in adult rat hippocampal slice cultures by a brief oxygen-glucose deprivation (OGD) [Hassen, G.W., Tian, D., Ding, D., Bergold, P.J., 2004. A new model of ischemic preconditioning using young adult hippocampal slice cultures. Brain Res. Brain Res. Protoc. 13, 135-143]. We have analyzed the changes in gene expression brought about by IPC in this model in order to understand the mechanisms involved. Total RNA was isolated at different time points following a brief OGD (3, 6 and 12 h) and used to probe genome-wide expression microarrays. Genes were identified that were significantly up- or down-regulated relative to controls. We placed genes that were differentially expressed into statistically significant groups based on Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and gene ontology (GO) terms. Genes involved in signal transduction, transcription, and oxidative phosphorylation are differentially expressed at each time point. The analysis demonstrates that alterations in signaling pathways (TGF-beta, Wnt, MAPK, ErbB, Toll-like receptor, JAK-STAT, VEGF) consistently accompany IPC. RT-PCR was used to confirm that members of these signaling pathways are regulated as predicted by the microarray analysis. We verified that protein translation following OGD is necessary for IPC. We also found that blocking the NMDA receptor during OGD does not significantly inhibit IPC in this model or produce large changes in gene expression. Our data thus suggests that changes in signaling pathways and their down-stream targets play an important role in triggering endogenous neuroprotection.

Increased excitability and decreased sensitivity to GABA in an animal model of dysplastic cortex.

PURPOSE: Cortical dysplasia (CD) is associated with epilepsy in both the pediatric and adult populations. The mechanism underlying seizures with cortical malformations is still poorly understood. To study the physiology of dysplastic cortex, we developed an experimental model of CD. METHODS: Pregnant rats were given intraperitoneal injections of carmustine (1-3-bis-chloroethyl-nitrosourea; BCNU) on embryonic day 15 (E15). Cortical histology was examined in the resulting pups at P0, P28, and P60. In addition, evoked and spontaneous field potential recordings were obtained in cortical slices from adult control and BCNU-exposed rats. Finally, we used whole-cell recordings to compare physiologic properties of pyramidal neurons and gamma-aminobutyric acid (GABA) responses in control and BCNU-treated animals. RESULTS: Features characteristic of CD were found in the offspring, including laminar disorganization, cytomegalic neurons, and neuronal heterotopias. Dysplastic cortex also contained abnormal clusters of Cajal-Retzius (CR) cells and disruption of radial glial fibers, as demonstrated with immunohistochemistry. Under conditions of partial GABAA-receptor blockade with 10 microM bicuculline methiodide (BMI), slices of dysplastic cortex demonstrated a significant increase in the number of spontaneous and evoked epileptiform discharges. Individual pyramidal neurons in dysplastic cortex were less sensitive to application of GABA compared with controls. CONCLUSIONS: BCNU exposure in utero produces histologic alterations suggestive of CD in rat offspring. Dysplastic cortex from this model demonstrates features of hyperexcitability and decreased neuronal sensitivity to GABA. Such physiologic alterations may underlie the increased epileptogenicity of dysplastic cortex.