Preoperative meningioma embolization reduces perioperative blood loss: a multi-center retrospective matched case-control study.

BACKGROUND AND PURPOSE: The utility of preoperative embolization remains controversial within the literature. Here, we evaluate whether preoperative meningioma embolization is effective in reducing intraoperative blood loss, safe to perform, and cost-effective when compared with surgical resection without preoperative embolization. METHODS: Twenty-nine patients with meningiomas were matched by tumor size and location to 29 control patients with meningiomas at another institution where preoperative embolization was not practiced. The variables evaluated were pre- and post-operative hemoglobin and hematocrit levels as a measure of operative blood loss and postoperative morbidity. The additional cost of undergoing angiography and embolization was calculated from hospital charges obtained from the billing department. RESULTS: The mean decrease in perioperative hemoglobin and hematocrit was 0.9 and 2.7, respectively, in the embolization group and 2.8 and 10.0, respectively, in the control group for a significant decrease in operative blood loss as measured by change in hematocrit and hemoglobin levels after surgery. There was no significant difference in operative blood loss when subdividing patients based on tumor location. There were no angiogram-related complications. Twenty-two of 29 patients (76%) underwent embolization of a feeding artery, whereas 7 patients underwent only a diagnostic angiogram. The mean additional charge per patient in the embolization group was $88,767. CONCLUSIONS: Preoperative embolization was safe and effective in reducing the overall perioperative blood loss in patients undergoing meningioma resection, as measured by the change in postoperative hemoglobin and hematocrit levels. However, the cost of embolization was significant.

Dual-center study comparing transradial and transfemoral approaches for flow diversion treatment of intracranial aneurysms.

BACKGROUND: The transfemoral approach (TFA) has been the traditional approach for neurointerventional cases. While the TFA allows for triaxial support in flow diverting stent cases, it is associated with access site complications. Recently, the transradial approach (TRA) has emerged as a safer alternative to the TFA. To the best of our knowledge, there have only been single-center studies comparing outcomes in flow diverter cases for these approaches. We demonstrate the safety and feasibility of the TRA for placement of flow diverting stents in the treatment of unruptured intracranial aneurysms at two high-volume centers. MATERIALS AND METHODS: We performed a retrospective review of prospectively collected institutional databases at two high-volume neuroendovascular centers. Cases from 2016 to 2018 of unruptured intracranial aneurysms treated by flow diverting stenting accessed through either the TRA or the TFA were compared. Patient demographics, procedural and radiographic metrics including location and size of the aneurysm, size, and length of the flow diverter implant, and fluoroscopic time were recorded. Puncture site complications and length of hospital stay were also included in the data analysis. RESULTS: There were three out of 29 TRA cases which were converted to the TFA. None of the TRA patients experienced site complications, whereas three TFA patients experienced site complications. While TRA and TFA patients did not differ significantly in their exposure to radiation, TRA patients experienced shorter hospital stays. CONCLUSIONS: While long-term studies are still lacking regarding this approach, we demonstrate that the TRA is a safe and feasible approach for flow diverter stent placement.

Total and partial posterior quadrant disconnection for medically refractory epilepsy: A systematic review.

PURPOSE: Posterior quadrant disconnection (PQD) is a surgical procedure for medically refractory epilepsy (MRE) involving diffuse regions of the temporo-parieto-occipital lobes. We sought to compare factors and efficacy according to PQD extent. METHODS: We performed a systematic review of the literature reporting the use of PQD since 2004. We analyzed various characteristics of pooled cases, including the role of preoperative studies in patient selection, intraoperative techniques, and outcomes. RESULTS: Our review of 137 patients from nine studies revealed 66% undergoing total PQD and 34% undergoing partial PQD. Interictal electroencephalography (EEG) findings were predominantly characterized as lateralized for total PQD (56%) and localized within the ipsilateral posterior quadrant in patients undergoing partial PQD (53%). Metabolic functional studies [positron emission tomography (PET) or ictal single-photon emission computed tomography (SPECT)] played a role in surgical decision-making in 42% of patients who underwent total PQD. Wada and/or functional magnetic resonance imaging (fMRI) was more often utilized for partial PQD (22%) than total PQD (3%) as was intracranial electroencephalography (icEEG) (30% versus 13%, respectively). Overall, 75% of total PQD patients achieved seizure freedom [defined as Engel I or International League Against Epilepsy (ILAE) Class 1 outcome] in comparison to 63% of partial PQD patients (p = .078). New visual field deficits were seen in 12% and new or worsened hemiparesis in 6%. For patients in either cohort, concordance of interictal and ictal EEG findings was found to be predictive of seizure freedom (p = .048). CONCLUSION: Both total and partial PQD represent effective alternatives for managing patients with MRE whose seizure onset zone (SOZ) involves a diffuse region within the posterior quadrant. While PET and/or SPECT frequently aided in the decision to proceed with total PQD, patients who underwent a tailored, partial multilobar resection were more likely to undergo Wada and/or fMRI testing as well as stage I icEEG studies.

Endoscopic Endonasal Transclival Odontoidectomy for Basilar Invagination: Operative Video and Technical Nuances.

Basilar invagination is a congenital or acquired craniovertebral junction abnormality where the tip of the odontoid process projects through the foramen magnum which can cause severe symptomatic compression of the brainstem and spinal cord. If left untreated, patients can develop progressive quadriparesis. Traditionally, basilar invagination can be treated with cervical traction and posterior stabilization. However, in irreducible cases, anterior decompression via a transoral or endonasal approach may be necessary. In this operative video, we demonstrate an endoscopic endonasal transclival approach for odontoidectomy to successfully treat a 37-year-old female with severe basilar invagination causing symptomatic compression on the cervicomedullary junction resulting in unsteady gait and motor weakness. The patient had Klippel-Feil syndrome where the C1 arch was assimilated to the foramen magnum and transclival drilling was needed to adequately access the odontoid process for removal. A second-stage posterior occipitocervical stabilization and fusion was performed the following day. Immediate postoperative imaging showed excellent decompression of the cervicomedullary junction. Postoperatively, the patient had significant improvement in gait and motor strength in all extremities, and was ambulating independently without assistance at 1 year after surgery. The endoscopic endonasal transclival odontoidectomy is a useful strategy to treat severe irreducible basilar invagination causing symptomatic neural compression. The surgical technique and nuances are described in a step-by-step fashion in this illustrative operative video. The link to the video can be found at: https://youtu.be/HL4K7KqJEJM.

Far Lateral Transcondylar Transtubercular Approach for Microsurgical Resection of Foramen Magnum Meningioma: Operative Video and Technical Nuances.

Surgical access to the ventral foramen magnum remains a technical challenge. With large lesions in this region compressing the brainstem and distorting the regional neurovascular relationships, formulating a surgical plan and its appropriate execution have crucial importance in achieving favorable outcomes. While the endoscopic endonasal approaches have gained increasing attention to access the clivus and the ventral brainstem, foramen magnum meningiomas are still preferred to be removed via an approach that obviates a trajectory through the nasopharyngeal mucosa. Therefore, the far lateral approach remains one of the most practical approaches for these challenging lesions. This operative video demonstrates the use of the far lateral transcondylar transtubercular approach to remove a large meningioma in the ventral foramen magnum in a 63-year-old male with progressive cervical myelopathy, presenting as spastic quadriparesis without any cranial nerve abnormality. Using a right-sided far lateral transcondylar transtubercular approach, the meningioma was exposed within the cerebellomedullary gutter engulfing the vertebral artery and distorting the course of the adjacent cranial nerves. Using the different corridors identified between the vertebral artery, spinal accessory, vagus, and hypoglossal nerves, multiple angles of attacks to the tumor were established and utilized to resect the lesion. A gross total resection was achieved and the patient was neurologically intact without any neurological deficits. This video demonstrates the importance of understanding the intricacies of neurovascular anatomy of the cervicomedullary region (i.e., the various triangles formed between these structures), and the effective use of these corridors to safely and efficiently remove a challenging ventral foramen magnum meningioma with neurovascular involvement, while preserving cranial nerve function. The surgical technique and nuances are described in a step-by-step fashion in this illustrative operative video. The link to the video can be found at: https://youtu.be/s1dFhuaRSt8 .

Acute Cerebrovascular Disorders and Vasculopathies Associated with Significant Mortality in SARS-CoV-2 Patients Admitted to The Intensive Care Unit in The New York Epicenter.

The current Coronavirus pandemic due to the novel SARS-Cov-2 virus has proven to have systemic and multi-organ involvement with high acuity neurological conditions including acute ischemic strokes. We present a case series of consecutive COVID-19 patients with cerebrovascular disease treated at our institution including 3 cases of cerebral artery dissection including subarachnoid hemorrhage. Knowledge of the varied presentations including dissections will help treating clinicians at the bedside monitor and manage these complications preemptively.

Management of Small Unruptured Intracranial Aneurysms: To Treat or Not to Treat?

Unruptured intracranial aneurysms measuring <7 mm in diameter have become increasingly prevalent due to advances in diagnostic imaging. The most feared complication is aneurysm rupture leading to a subarachnoid hemorrhage. Based on the current literature, the 3 main treatments for an unruptured intracranial aneurysm are conservative management with follow-up imaging, endovascular coiling, or surgical clipping. However, there remains no consensus on the best treatment approach. The natural history of the aneurysm and risk factors for aneurysm rupture must be considered to individualize treatment. Models including population, hypertension, age, size of aneurysm, earlier subarachnoid hemorrhage from a prior aneurysm, site of aneurysm score, Unruptured Intracranial Aneurysm Treatment Score, and advanced neuroimaging can assist physicians in assessing the risk of aneurysm rupture. Macrophages and other inflammatory modulators have been elucidated as playing a role in intracranial aneurysm progression and eventual rupture. Further studies need to be conducted to explore the effects of therapeutic drugs targeting inflammatory modulators.

Posterior Approach for a Ventral Intradural Extramedullary Meningioma: 2-Dimensional Operative Video.

Ventral thoracic meningiomas are rare entities in which the spinal cord is attenuated and draped over the meningioma symmetrically. This is a challenging surgical entity compared to typical intradural meningiomas, which nearly always eccentrically displace the cord. In these more common meningiomas, surgical access is fairly straightforward as the meningioma is often visualized upon opening the meninges. Resection can be more safely performed with the cord largely shifted. In cases of ventral meningioma, the tumor is hidden ventral to the spinal cord, and techniques to safely mobilize the spinal cord must be utilized. We demonstrate that an entirely posterior approach allows complete resection of a ventrally situated mass. After careful identification and sectioning of the dentate ligament at multiple levels on the right side of the canal, we then suture and rotate the dentate ligament at each site, thereby allowing progressive visualization of the ventral meningioma. A narrow, but viable, working corridor to the tumor allows safe debulking. Once it is felt that the tumor can no longer be safely excised through the created corridor, we then disconnect our dentate sutures and move to the other side of the canal. Similarly, the dentate is sectioned and sutured so that the contralateral aspect of the meningioma can be visualized and debulked. The tumor can then be safely removed. A standard posterior approach and midline durotomy allows this bilateral approach to a ventrally situated meningioma and, therefore, in our mind, represents a safe and also highly effective road to resection. Patient consent was obtained prior to publication.

Proneurotrophins Induce Apoptotic Neuronal Death After Controlled Cortical Impact Injury in Adult Mice.

The p75 neurotrophin receptor (p75NTR) can regulate multiple cellular functions including proliferation, survival, and apoptotic cell death. The p75NTR is widely expressed in the developing brain and is downregulated as the nervous system matures, with only a few neuronal subpopulations retaining expression into adulthood. However, p75NTR expression is induced following damage to the adult brain, including after traumatic brain injury, which is a leading cause of mortality and disability worldwide. A major consequence of traumatic brain injury is the progressive neuronal loss that continues secondary to the initial trauma, which ultimately contributes to cognitive decline. Understanding mechanisms governing this progressive neuronal death is key to developing targeted therapeutic strategies to provide neuroprotection and salvage cognitive function. In this study, we demonstrate that a cortical impact injury to the sensorimotor cortex elicits p75NTR expression in apoptotic neurons in the injury penumbra, confirming previous studies. To establish whether preventing p75NTR induction or blocking the ligands would reduce the extent of secondary neuronal cell death, we used a noninvasive intranasal strategy to deliver either siRNA to block the induction of p75NTR, or function-blocking antibodies to the ligands pro-nerve growth factor and pro-brain-derived neurotrophic factor. We demonstrate that either preventing the induction of p75NTR or blocking the proneurotrophin ligands provides neuroprotection and preserves sensorimotor function.

Neuroendovascular Cerebral Sinus Stenting in Idiopathic Intracranial Hypertension.

Idiopathic intracranial hypertension (IIH) is a rare, ill-understood disease of significant morbidity. Because the pathophysiology is poorly understood, treatment protocols are not uniform and are directed towards alleviating the most common symptoms: headache and visual loss. In this review, we analyze 25 case series, all of which included IIH patients (n = 408) who were treated with placement of a venous sinus stent. Among 342 patients who had headache, 240 patients (70.2%) had improvement or resolution of headache after the stent insertion. Of the 217 patients documented to have visual problems, visual acuity was improved or stabilized in 161 patients (74.2%). Of the 304 patients with papilledema, 257 showed resolution or improved (84.5%). Of the 124 patients who presented with pulsatile tinnitus, it was resolved in 110 patients (88.7%) after stent placement. Endovascular management of dural sinus stenosis is therefore clinically efficacious in patients with IIH who have failed medical and surgical therapy.

Chondromyxoid Fibroma of the Sacral Spine.

Background and Importance. Chondromyxoid fibromas are rare tumors of cartilaginous origin typically found in long bones. They usually present during the second and third decades of life. In this case report, we describe the case of a 60-year-old male who presented with back pain and was later found to have a sacral mass. Further immunohistochemical analysis determined that the mass was a chondromyxoid fibroma. Clinical Presentation. A 60-year-old male presented with worsening lower back pain over the course of 2 years. Magnetic resonance imaging demonstrated a destructive mass centered at S4 with heterogeneous enhancement. The patient underwent an S3-to-Co1 laminectomy for gross total resection of the tumor. Histology demonstrated a biphasic, lobulated appearance, characteristic of a chondromyxoid fibroma. The tissue stained faintly positive for multicytokeratin, and it was negative for markers S-100 protein and brachyury, indicating that it was not a chordoma. Conclusion. Only 8 cases have documented sacral chondromyxoid fibroma. As these are exceedingly rare tumors, especially within the sacral spine, the differential diagnosis includes other malignant tumors more likely to be found in the spine, particularly chordomas and chondrosarcomas. Immunohistochemistry and histology are essential in making a definitive diagnosis. This case provides a comprehensive illustration of the clinical presentation, radiographic findings, and immunohistochemistry of sacral chondromyxoid fibroma.

First case series of the transradial approach for neurointerventional procedures in pediatric patients.

OBJECTIVE: The transradial approach (TRA) has been widely adopted by interventional cardiologists but is only now being accepted by neurointerventionalists. The benefits of the TRA over the traditional transfemoral approach (TFA) include reduced risk of adverse clinical events and faster recovery. The authors assessed the safety and feasibility of the TRA for neurointerventional cases in the pediatric population. METHODS: Pediatric patients undergoing cerebrovascular interventions since implementation of the TRA at the authors' institution were retrospectively reviewed. Pertinent patient information, procedure indications, vessels catheterized, fluoroscopy time, and complications were reviewed. RESULTS: There were 4 patients in this case series, and their ages ranged from 13 to 15 years. Each patient tolerated the procedure performed using the TRA without any postprocedural issues, and only 1 patient experienced radial artery spasm, which resolved with the administration of intraarterial verapamil. None of the patients required conversion to the TFA. CONCLUSIONS: The TRA can be considered a safe alternative to the TFA for neurointerventional procedures in the pediatric population and provides potential advantages. However, as pediatric patients require special consideration due to their smaller-caliber arteries, routine use of ultrasound guidance is advised when attempting the TRA.

Epidermoid Cyst of the Lumbar Spine After Lumbar Puncture: A Clinical, Radiographic, and Pathologic Correlation.

BACKGROUND: Epidermoid cysts can rarely arise as a late complication of lumbar puncture. We describe a young man who had a remote history of a lumbar puncture and who was subsequently found to have a lumbar spinal epidermoid cyst on imaging, after presenting with lower extremity radicular pain. CASE DESCRIPTION: A 24-year-old man with a remote history of lumbar puncture presented with lower back pain and radicular leg pain which had been ongoing for over a year. Despite conservative management, the patient's symptoms progressed to worsening back pain and left L4 radiculopathy. Magnetic resonance imaging of the lumbar spine demonstrated a peripherally enhancing, intradural, extramedullary lesion at L4-5. Diffusion-weighted imaging revealed diffusion restriction within the lesion, characteristic of an epidermoid cyst. The patient underwent an L4-5 laminectomy for resection of the intradural tumor. The lesion was noted to contain pearly white granules consistent with the appearance of an epidermoid cyst. Histopathology confirmed the diagnosis. On follow-up examination, the patient demonstrated improvement of his back pain and resolution of radicular symptoms. CONCLUSIONS: Lumbar spinal epidermoid cysts may be either congenital or secondary to an iatrogenic cause. This patient had a remote history of lumbar puncture during workup for meningitis as a child. As a complication of a lumbar puncture, the formation of an epidermoid cyst can occur and is thought to be the result of implanted cutaneous tissue. This case provides a comprehensive illustration of the clinical, radiographic, intraoperative, and pathologic findings consistent with an iatrogenic epidermoid cyst.

Machine Learning and Artificial Intelligence in Neurocritical Care: a Specialty-Wide Disruptive Transformation or a Strategy for Success.

PURPOSE OF REVIEW: Neurocritical care combines the complexity of both medical and surgical disease states with the inherent limitations of assessing patients with neurologic injury. Artificial intelligence (AI) has garnered interest in the basic management of these complicated patients as data collection becomes increasingly automated. RECENT FINDINGS: In this opinion article, we highlight the potential AI has in aiding the clinician in several aspects of neurocritical care, particularly in monitoring and managing intracranial pressure, seizures, hemodynamics, and ventilation. The model-based method and data-driven method are currently the two major AI methods for analyzing critical care data. Both are able to analyze the vast quantities of patient data that are accumulated in the neurocritical care unit. AI has the potential to reduce healthcare costs, minimize delays in patient management, and reduce medical errors. However, these systems are an aid to, not a replacement for, the clinician's judgment.

Artificial intelligence in neurocritical care.

BACKGROUND: Neurocritical care combines the management of extremely complex disease states with the inherent limitations of clinically assessing patients with brain injury. As the management of neurocritical care patients can be immensely complicated, the automation of data-collection and basic management by artificial intelligence systems have garnered interest. METHODS: In this opinion article, we highlight the potential artificial intelligence has in monitoring and managing several aspects of neurocritical care, specifically intracranial pressure, seizure monitoring, blood pressure, and ventilation. RESULTS: The two major AI methods of analytical technique currently exist for analyzing critical care data: the model-based method and data driven method. Both of these methods have demonstrated an ability to analyze vast quantities of patient data, and we highlight the ways in which these modalities of artificial intelligence might one day play a role in neurocritical care. CONCLUSIONS: While none of these artificial intelligence systems are meant to replace the clinician's judgment, these systems have the potential to reduce healthcare costs and errors or delays in medical management.

Endoscopic Fourth Ventriculostomy: Suboccipital Transaqueductal Approach for Fenestration of Isolated Fourth Ventricle: Case Report and Technical Note.

BACKGROUND: Trapped or isolated fourth ventricle is a known, late sequela after lateral ventricular shunt placement for hydrocephalus, particularly after infection or hemorrhage. It may cause brainstem compression and insidiously present with ataxia, dysarthria, and intracranial hypertension, further delaying diagnosis. There is no universally agreed on treatment algorithm, and options include open fenestration through a suboccipital craniotomy, fourth ventricle shunting, and minimally invasive options including endoscopic stenting and fenestration through a precoronal approach. CASE DESCRIPTION: We describe a young child with epilepsy and symptomatic brainstem compression from a dilated fourth ventricle, with a history of streptococcal parietal abscess and posthemorrhagic hydrocephalus requiring shunt placement. Given his history of infection and nearly neurologically intact examination, we pursued minimally invasive endoscopy through a suboccipital, transaqueductal approach to fenestrate his fourth ventricle. CONCLUSIONS: Magnetic resonance imaging (MRI) demonstrated complex, loculated hydrocephalus and a dilated fourth ventricle. Under electromagnetic navigation, we endoscopically fenestrated his fourth ventricle using a rarely described suboccipital, transaqueductal approach. He tolerated the procedure without complication and improved neurologically, although his follow-up MRI demonstrated no change in fourth ventricular dilation at 1 year. Although there was no decrease in size of the fourth ventricle on follow-up MRI, we describe an alternative, well-tolerated, suboccipital approach for the management of a trapped fourth ventricle. Fenestration of a web of tissue in the aqueduct of Sylvius provided long-term clinical improvement and may provide a rescue approach for patients who are not candidates for standard approaches.

Translabyrinthine Approach for Resection of Large Cystic Acoustic Neuroma: Operative Video and Technical Nuances of Subperineural Dissection for Facial Nerve Preservation.

The translabyrinthine approach is advantageous for the resection of large acoustic neuromas compressing the brainstem when hearing loss is nonserviceable. This approach provides wide access through the presigmoid corridor without prolonged cerebellar retraction. Early identification of the facial nerve at the fundus is also achieved. In this operative video atlas manuscript, the authors demonstrate a step-by-step technique for microsurgical resection of a large cystic acoustic neuroma via a translabyrinthine approach. The nuances of microsurgical and skull base technique are illustrated including performing extracapsular dissection of the tumor while maintaining a subperineural plane of dissection to preserve the facial nerve. This strategy maximizes the extent of removal while preserving facial nerve function. A microscopic remnant of tumor was left adherent to the perineurium. A near-total resection of the tumor was achieved and the facial nerve stimulated briskly at low thresholds. Other than preexisting hearing loss, the patient was neurologically intact with normal facial nerve function postoperatively. In summary, the translabyrinthine approach and the use of subperineural dissection are important strategies in the armamentarium for surgical management of large acoustic neuromas while preserving facial nerve function. The link to the video can be found at: https://youtu.be/zld2cSP8fb8 .

Retrosigmoid Transmeatal Approach for Resection of Acoustic Neuroma: Operative Video and Technical Nuances of Subperineural Dissection for Facial Nerve Preservation.

The retrosigmoid (suboccipital) approach is the workhorse for most acoustic neuromas in the cerebellopontine angle. In this operative video atlas manuscript, the authors demonstrate the nuances of the subperineural dissection technique for microsurgical resection of an acoustic neuroma via the retrosigmoid transmeatal approach. The plane is developed by separating the perineurium of the vestibular nerve away from the tumor capsule. This perineurium provides a protective layer between the tumor capsule and the facial nerve which serves as a buffer to avoid direct dissection and potential trauma to the facial nerve. Using this technique during extracapsular tumor dissection helps to maximize the extent of tumor removal while preserving facial nerve function. A gross total resection of the tumor was achieved, and the patient exhibited normal facial nerve function ( Fig. 1 ). In summary, the retrosigmoid transmeatal approach with the use of subperineural dissection are important strategies in the armamentarium for surgical management of acoustic neuromas with the goal of maximizing tumor removal and preserving facial nerve function ( Fig. 2 ). The link to the video can be found at: https://youtu.be/L3lPtSvJt60 .