Adamantinomatous craniopharyngioma in the molecular age and the potential of targeted therapies: a review.

Pediatric adamantinomatous craniopharyngiomas (ACPs) are histologically benign brain tumors that often follow an aggressive clinical course. Arising in the sellar/suprasellar region, they grow in close proximity to critical neurological and vascular structures and can result in significant neuroendocrine morbidity. First-line treatment often involves surgical resection with or without radiotherapy and has been associated with significant morbidity and poor quality of life outcomes. As a result, the discovery of alternative effective and safe treatments is clearly desirable. In recent years, laboratory studies have harnessed sophisticated techniques to identify the upregulation of several markers that may represent potential therapeutic targets. These targets include IL-6, PD1/PD-L1, MEK, IDO-1, and others. Agents that target these pathways exist, and there is an opportunity to investigate their potential efficacy in the treatment of ACP. Trials investigating some of these agents as monotherapy and in combination for the treatment of pediatric ACP are underway or in development. If positive, these trials may result in a paradigm shift in treatment that will hopefully result in reduced morbidity and better outcomes for patients.

A brief history of cortical functional localization and its relevance to neurosurgery.

Modern cortical mapping is a cornerstone for safe supratentorial glioma resection in eloquent brain and allows maximal resection with improved functional outcomes. The unlocking of brain functionality through close observation and eventually via cortical stimulation has a fascinating history and was made possible by contributions from early physician-philosophers and neurosurgery's founding fathers. Without an understanding of brain function and functional localization, none of today's modern cortical mapping would be possible.

Correction to: Preservation of olfaction in anterior midline skull base meningiomas: a comprehensive approach.

Result is incorrect.

Preservation of olfaction in anterior midline skull base meningiomas: a comprehensive approach.

BACKGROUND: Olfaction is an undervalued sense in neurosurgery. Attempted surgical resection of anterior cranial fossa meningiomas puts the olfactory pathway at risk. Preservation of olfaction may increase the postoperative quality of life. Objective assessment of olfaction may inform clinical decision-making and influence the selection of operative approaches for surgical resection. METHODS: We reviewed all patients who underwent surgical resection for midline anterior skull base meningiomas from July 1, 2014, through December 31, 2017. Patient demographics, tumor size, operative approach, pre- and postoperative deficits, and Simpson grade were collected and analyzed. Postoperative olfaction was assessed by clinical evaluation as well as objective evaluation using the University of Pennsylvania Smell Identification Test (UPSIT). RESULTS: Twenty-eight patients (10 male, 18 female) were included with an average age of 53.8 years (range 27-80 years). Twenty-six patients underwent craniotomy for resection, while 2 patients had endoscopic approaches. Average tumor volume was 402.1 cm3 (6.6-2507.7 cm3). Preoperatively, five patients (17.8%) presented with olfactory impairment. Objectively, 50% of patients (14/28) consented and completed the UPSIT. The average postoperative UPSIT score was 25.8/40 (9/40-38/40). Two patients not identified on clinical assessment alone demonstrated postoperative olfactory deficit on UPSIT (2/14). CONCLUSION: There are limited published studies evaluating olfaction in patients who undergo skull-based approaches for anterior fossa meningiomas. Our series showed the highest olfaction preservation rate (87.5%) using a comprehensive strategy and multitude of surgical approaches based on the olfactory function and tumor characteristics.

Differential Pressure Shunt for Simultaneous Diversion of Ventricular Fluid and Extracerebral Fluid.

BACKGROUND/AIMS: The management of extracerebral collections of fluid in patients with hydrocephalus can be problematic for either their simultaneous separate management or sequential management, each of which may require multiple surgeries and the management of external drains. The object of this report is to review the experience with a shunt configuration that simultaneously diverts ventricular fluid and extracerebral fluid, whether subdural or subarachnoid in location, through different outflow resistances. METHODS: The medical records, including neuroimaging of patients with hydrocephalus and clinically significant extracerebral collections of low density who were managed by implanting a differential pressure type shunt, were retrospectively reviewed. RESULTS: Four patients, 3 children and 1 adult, met inclusion criteria. Three had the entire differential pressure shunt implanted under 1 anesthetic, and 1 had a catheter inserted into the subdural space and connected into an existing ventriculoperitoneal shunt system. The extracerebral fluid collections cleared in all 4 patients, and the CSF shunt continued to function normally. CONCLUSION: A single surgical procedure to implant a differential pressure shunt can simultaneously drain and obliterate an extracerebral fluid collection while managing the hydrocephalus. Compared to routines that include external drainage, differential pressure shunting requires fewer surgeries, shorter hospitalization, with expected less expense.

Acute Posterior Multifocal Placoid Pigment Epitheliopathy Associated with Stroke: A Case Report and Review of the Literature.

BACKGROUND: Present a case report of acute posterior multifocal placoid pigment epitheliopathy (APMPPE) associated with stroke along with the serologic findings, diagnostic findings, and treatment in addition to presenting a review of other case reports to date in literature. With this information, we are attempting to identify key diagnostic features and appropriate treatment options for patients with this disease. METHODS: Presentation of case report, background on APMPPE, review of the literature and previous case reports, and discussion of diagnostic workup and treatment options for these patients. RESULTS: There are 28 well-described case reports in the literature to date, not including our case report; 23 had documented radiographic findings consistent with parenchymal injury, ischemic stroke, hemorrhagic stroke, or cerebral venous thrombosis. We report a 23-year-old right-handed man with left hemiparesis, ischemic strokes, and angiographic findings characteristic of cerebral vasculitis 4 months after he was diagnosed with APMPPE. CONCLUSIONS: Based on our present case and previously documented cases to date, corticosteroid therapy with potential escalation of care to immunomodulatory treatment appears to benefit clinical outcomes.

Periprocedural management of ruptured blister aneurysms treated with pipeline flow diversion.

Background: Blister aneurysms are high-risk intracranial vascular lesions. Definitive treatment of these lesions has been challenging. Severe disability or mortality rates are as high as 55% when these lesions are treated with open surgery. Recent data show that flow diversion is a safe and effective alternative treatment for blister aneurysms. Rerupture of the functionally unsecured lesion remains a concern as flow diversion does not immediately exclude the aneurysm from the circulation. Methods: A retrospective review was performed of any patients with ruptured blister aneurysms treated with a pipeline embolization device between 2010 and 2020 at the University of Colorado. Results: In this paper, we present the results of the intensive care management of ruptured intracranial blister aneurysms after flow-diverting stent placement. Conclusion: Despite the need for dual antiplatelet therapy and the delayed occlusion of blister aneurysms treated with flow diversion, we did not find an increase in periprocedural complications.

Technical Nuances and Outcomes of Telescoping Pipeline Flow Diverters: A Multicenter Study.

BACKGROUND: "Telescoping" multiple overlapping Pipeline Embolization Devices (PEDs; Medtronic) has increased their utility by allowing for more impermeable coverage and providing the ability to off-set landing zone sites and extend treatment constructs. OBJECTIVE: To consider the technical nuances and challenges of telescoping PEDs for the treatment of intracranial aneurysms. METHODS: Databases from 3 U.S. academic neurovascular centers were retrospectively queried to identify patients with intracranial aneurysms treated with multiple PED constructs. Data on patient and aneurysm characteristics, as well as outcomes including Raymond-Roy occlusion classification, modified Rankin Scale score, and complications, were gathered. RESULTS: Forty-six patients had 48 intracranial aneurysms treated, including 16 (33%) in whom placement of telescoping PEDs was planned. Fourteen (30%) patients presented with a ruptured aneurysm. Twenty-one aneurysms (44%) were treated with proximal extension, 13 (27%) with distal extension, and 14 (29%) with PED placement inside one another. Thirty (70%) patients had complete aneurysm occlusion at follow-up. Two (4%) patients had to be retreated. Three patients with unruptured and 1 with ruptured aneurysm had a permanent intraprocedural complication. We present descriptive cases illustrating PEDs that were placed inside one another, proximally, distally, and to improve wall apposition because of vessel tortuosity. CONCLUSION: Our data indicate a higher than expected complication rate that is likely because of the technical complexity of these cases. The case illustrations presented demonstrate the indications and challenging aspects of telescoping PEDs.

Tailored Treatment Options for Cerebral Cavernous Malformations.

The diagnosis and treatment of cerebral cavernous malformations (CCMs), or cavernomas, continues to evolve as more data and treatment modalities become available. Intervention is necessary when a lesion causes symptomatic neurologic deficits, seizures, or has high risk of continued hemorrhage. Future medical treatment directions may specifically target the pathogenesis of these lesions. This review highlights the importance of individualized treatment plans based on specific CCM characteristics.

Untangling the Modern Treatment Paradigm for Unruptured Brain Arteriovenous Malformations.

Brain arteriovenous malformations (AVMs) often present treatment challenges. Patients with unruptured AVMs must consider not only whether they want to be treated, but what treatment modality they would prefer. Vascular neurosurgeons, neurointerventional surgeons, and stereotactic radiosurgeons must in turn guide their patients through the most appropriate treatment course considering the risk of AVM rupture, an individual AVM's characteristics, and patient preferences. In this review we will look at how the clinical trial "A Randomized Trial of Unruptured Brain Arteriovenous Malformations (ARUBA)" has influenced the approach to unruptured brain AVMs and the treatment modalities available to clinicians to deal with these formidable lesions.

Predictors of 90-Day Readmission Rate After Unruptured Intracranial Aneurysm Repair.

OBJECTIVE: The repair of unruptured intracranial aneurysms has increased since 2000. In this study, we analyzed the Nationwide Readmission Database (NRD) to determine the rate of 90-day readmission. Our objective is to examine readmission trends after unruptured aneurysm repair. METHODS: This study used the 2013 and 2014 NRD. Patient data included standard demographic, comorbidity, and payer information. We selected patients who had undergone microsurgical or endovascular repair for a nonruptured aneurysm. We excluded patients who were under 18 years of age, had a subarachnoid hemorrhage, or were discharged to home the same day. Readmission was calculated by counting the number of days between the end of the index visit and earliest readmission date. RESULTS: A total of 2180 of 29,694 patients (7.34%) were readmitted within 90 days of their initial hospitalization. They were younger (mean, 52.6 years; 95% confidence interval [CI], 51.4-53.8) than patients not readmitted (mean, 57.4 years; 95% CI, 57.1-57.8; P < 0.0001). In total, endovascular repair was more frequent than microsurgery (79.8% vs. 20.2%, respectively). Mean days to readmission was 41.8 (95% CI, 39.7-43.9) and was higher for women (P < 0.0001). The odds ratio for readmission after an endovascular repair was 1.54 (95% CI, 1.27-1.86). CONCLUSIONS: In this study of over 28,000 patients treated for an unruptured aneurysm, the 90-day readmission rate was 7.34%. Endovascular patients had higher odds of readmission than microsurgical patients. Patients with common medical comorbidities (hypertension, obesity, renal failure, and diabetes) were less likely to be readmitted than patients without those conditions.

Intraosseous Cannulation of a Calvarial Diploic Vein for Embolization of a Symptomatic Dural Arteriovenous Fistula: A Technical Case Report.

BACKGROUND AND IMPORTANCE: Dural arteriovenous fistulas (DAVFs) may present unique challenges for treatment depending on the anatomy and pattern of venous drainage. If endovascular techniques are to be employed, the DAVF must be amenable to transvenous or transarterial therapy. When access of peripheral vasculature does not provide a straightforward path, less conventional options may be available. This case highlights a novel, technically simple, and effective approach for the treatment of a subset of DAVFs, with venous drainage through calvarial diploic veins, that would make endovascular treatment otherwise challenging or impossible. CLINICAL PRESENTATION: We present a case of a 66-yr-old female patient who was diagnosed with a symptomatic DAVF located along the sphenoid ridge with a large intraosseous channel containing the draining vein of the fistula. This lesion was successfully treated with transcranial endovascular embolization via direct intraosseous cannulation of the calvarial diploic vein. This novel approach obviated the need for a full-thickness craniotomy, afforded only minimal bone loss, and preserved the integrity of the dura. A 3-mo follow-up angiogram confirmed complete cure of the DAVF with no residual arteriovenous shunt. At 20 mo postembolization, the patient was symptom free, with no reported neurologic deficits. Complete diagnostic work-up, treatment planning in a multidisciplinary environment, and a novel approach for endovascular embolization utilizing a hybrid operating suite played key roles in the successful implementation of this technique. CONCLUSION: This is the first report of direct intraosseous cannulation of a calvarial diploic vein for successful transcranial endovascular embolization of a symptomatic DAVF.

Use of the PulseRider Device in the Treatment of Ruptured Intracranial Aneurysms: A Case Series.

BACKGROUND: Wide-necked intracranial aneurysms present unique treatment challenges in the setting of subarachnoid hemorrhage. New generations of endoluminal devices (stents) have expanded our ability to treat complex aneurysms. The PulseRider Aneurysm Neck Reconstruction Device (PulseRider [Cerenovus, Irvine, California, USA]) is new to the U.S. market after receiving Food and Drug Administration approval in June 2017. Official recommendation for use of the PulseRider is with dual antiplatelet therapy (DAPT). Its design has been hypothesized to carry a lower risk of thromboembolic complications in the circumstance that DAPT needs to be discontinued. METHODS: Between March and June 2018, we treated 4 cases of ruptured wide-necked basilar tip aneurysms at the University of Colorado Hospital, Aurora, Colorado, with PulseRider-assisted coil embolization. Imaging and chart reviews were performed retrospectively on each of these patients. RESULTS: All 4 aneurysms were successfully treated with PulseRider-assisted coil embolization. There were no periprocedural hemorrhages and no postprocedural reruptures. Two patients developed nonocclusive thrombi in the posterior cerebral arteries at the time of coiling, which was resolved with intra-arterial glycoprotein IIb/IIIa receptor antagonists. Two patients developed external ventricular drain-associated hemorrhages, only one of which developed after the administration of DAPT. All patients were eventually discharged to home. CONCLUSIONS: The PulseRider device represents a novel design for stent-assisted coil embolization. We report a small but promising series of its successful use in the acute treatment of wide-necked, ruptured basilar artery aneurysms. Additional experience is needed to determine if this device has a place in our armamentarium for treatment of ruptured aneurysms.

Minimally invasive endoscopic-assisted approaches to the posterior fossa.

Modern surgical approaches are becoming more minimalistic, associated with the term "minimally invasive." The endoscope provides a more panoramic anatomical view in addition to the ability to access narrow deep corners with decent illumination and clear visualization. Endoscopic assisted microsurgery through a tailored small craniotomy is the foundation of keyhole surgery. The endoscope can be advanced deeper into the field, thus enhancing an exposure and allowing bimanual dissection, ultimately providing smaller craniotomies and tailored key exposures. The term "minimally invasive" became associated with reduction of overall tissue injury, decreased potential complications, reduced recovery times/hospital stay, and overall reduced costs. This minimally invasive concept became successfully applicable to diverse pathologies in the three cranial fossae. The posterior fossa houses the most critical neurovascular structures of the brain in an intricate and complex anatomical organization. In this manuscript, we describe keyhole endoscopic-assisted approaches to different regions of the posterior fossa. Five corridors for these approaches are described: 1) midline supracerebellar-infratentorial to the pineal region; 2) upper cerebellopontine angle (CPA) to the trigeminal region; 3) middle cerebellopontine angle to the vestibulocochlear region and internal auditory meatus; 4) inferior cerebellopontine angle to the jugular foramen region and lower cranial nerves; and 5) midline infracerebellar to posterior foramen magnum and the craniocervical junction. We then present a general review of the published literature and case examples demonstrating the effectiveness of the endoscopic-assisted keyhole concept.

Embolization of Head and Neck Vascular Malformations using Serial Arterial Embolization Followed by Dominant Arterial Embolization with Two Microcatheter Technique.

PURPOSE: Head and neck arteriovenous malformation (AVM) and fistulae treatment without reflux and with nidal penetration are challenging. We describe a case series including adult and pediatric patients utilizing a specific two-microcatheter technique using Onyx with strategic embolization of small feeding branches prior to dominant branch embolization. We aim to demonstrate the safety and efficacy of this technique. PATIENT SELECTION: Head and neck vascular malformation cases were reviewed from 2010 to 2017. 11 patients between 2010 and 2017 were treated with serial embolization along with Onyx embolization utilizing a two-microcatheter technique. Five patients had cerebral AVMs, three had dural arteriovenous fistulae, two had mandibular AVMs, and one had a posterior neck AVM. Vascular anatomy, location, and procedural details were recorded. TECHNIQUE: During procedures 1-4, smaller arterial feeders were embolized first to maximally decrease the intranidal pressure at the time of the embolization of the major residual feeder. The dominant residual feeder was then embolized using two catheters. Coils followed by Onyx were initially deployed through the proximal catheter to form a dense plug. The plug was allowed to solidify for 30 min. Aggressive embolization of the nidus was then performed through the distal catheter. RESULTS: All 11 patients had excellent treatment results with complete (6) or near-complete (5) obliteration of the vascular malformation nidus. No procedural complications were noted, specifically no strokes, hemorrhages, or unintentionally retained catheter fragments occurred. CONCLUSION: AVMs and fistulae are challenging to treat. A two-microcatheter technique for Onyx embolization with prior embolization of smaller arterial feeders is a safe and efficacious treatment option. This technique allows for maximal nidus penetration while minimizing the risk of nontarget embolization/reflux. In all cases, we achieved excellent results with complete or near-complete obliteration of the vascular malformation nidus.

Expanding the endoscopic transpterygoid corridor to the petroclival region: anatomical study and volumetric comparative analysis.

OBJECTIVE The endoscopic endonasal transmaxillary transpterygoid (TMTP) approach has been the gateway for lateral skull base exposure. Removal of the cartilaginous eustachian tube (ET) and lateral mobilization of the internal carotid artery (ICA) are technically demanding adjunctive steps that are used to access the petroclival region. The gained expansion of the deep working corridor provided by these maneuvers has yet to be quantified. METHODS The TMTP approach with cartilaginous ET removal and ICA mobilization was performed in 5 adult cadaveric heads (10 sides). Accessible portions of the petrous apex were drilled during the following 3 stages: 1) before ET removal, 2) after ET removal but before ICA mobilization, and 3) after ET removal and ICA repositioning. Resection volumes were calculated using 3D reconstructions generated from thin-slice CT scans obtained before and after each step of the dissection. RESULTS The average petrous temporal bone resection volumes at each stage were 0.21 cm3, 0.71 cm3, and 1.32 cm3 (p < 0.05, paired t-test). Without ET removal, inferior and superior access to the petrous apex was limited. Furthermore, without ICA mobilization, drilling was confined to the inferior two-thirds of the petrous apex. After mobilization, the resection was extended superiorly through the upper extent of the petrous apex. CONCLUSIONS The transpterygoid corridor to the petroclival region is maximally expanded by the resection of the cartilaginous ET and mobilization of the paraclival ICA. These added maneuvers expanded the deep window almost 6 times and provided more lateral access to the petroclival region with a maximum volume of 1.5 cm3. This may result in the ability to resect small-to-moderate sized intradural petroclival lesions up to that volume. Larger lesions may better be approached through an open transcranial approach.

Techniques for Achieving Hemostasis from Choanoid Cranial Foramina.

OBJECTIVE: This report describes 2 techniques for controlling otherwise difficult-to-control hemorrhage from choanoid bony foramina. METHODS: Medical records of 3 patients in whom vigorous and difficult-to-control bleeding from choanoid cranial foramina was successfully halted are reviewed. RESULTS: In 2 patients, vigorous arterial bleeding from the foramen spinosum was controlled with a wooden peg. In 1 patient, vigorous venous bleeding from a foramen in the convexity of the occipital bone was controlled with a wedge of bone. CONCLUSIONS: Vigorous bleeding, whether arterial or venous, from choanoid foramina can be quickly and reliably controlled by the techniques described.

Third Ventricular Cerebrospinal Fluid Cysts of Thalamic Origin: Review of Embryologic Origin, Presentation, and Management Strategies with a Case Series.

OBJECTIVE: Third ventricular cerebrospinal fluid (CSF) cysts of thalamic origin are rare. The objective of this study is to review their possible pathogenesis, clinical presentation, and management strategies with a case series describing management via an endoscopic approach with fenestration using a single burr-hole technique. METHODS: A systematic literature review of reported cases of thalamic cysts was conducted with further meta-analysis of CSF cysts that involve the third ventricle. The mode of presentation, pathologic analysis, surgical management, and outcomes were analyzed. RESULTS: Twenty-two studies reported between 1990 and 2013 described 42 cases of thalamic cyst. Of those cases, 13 were consistent with CSF cyst that originated in the thalamus and involved the third ventricle. Eight cases (61.5%) were treated via endoscopic fenestration, 2 cases (15.4%) were surgically drained, 2 cases (15.4%) were stereotactically aspirated, and 1 case (7.69%) was observed. The most common presenting symptoms were gait disturbance (26.3%) and headaches (26.3%) followed by tremors (15.8%) and weakness (15.8%). In our series, a single burr-hole technique was a successful definitive treatment, with an average period of 23 months. CONCLUSIONS: Third ventricular CSF cysts of thalamic origin most commonly present with hydrocephalus. They can be safely definitively treated via endoscopic fenestration to the CSF circulation using a single burr-hole technique. Long-term follow-up shows lasting improvement in symptoms without reaccumulation of the cyst.

Removal of Vagus Nerve Stimulator Leads and Reuse of Same Site for Reimplantation: Technique and Experience.

OBJECTIVE: This report describes the authors' experience and technique in removing vagus nerve stimulator leads, including coils, and reuse of the same site on the vagus nerve for implantation of new coils. METHODS: The charts of all patients who underwent complete removal by the authors of vagus nerve stimulator leads between 1 September 2001 and 1 July 2015 were retrospectively reviewed. RESULTS: Thirty patients underwent 31 surgeries for removal of vagus nerve stimulator leads. Complete removal, including proximal coils around the vagus nerve, was achieved in all cases. Reimplantation was performed immediately at the same location in 24 patients, delayed in 1 patient, and never replaced in 6. Long-term vocal cord paralysis followed 2 of 9 surgeries performed with sharp dissection and followed one of 22 surgeries in which dissection was performed with monopolar microneedle electrocautery. CONCLUSIONS: Vagus nerve stimulator coils can be removed from the vagus nerve, via monopolar microneedle electrocautery, and the same site reused for immediate reimplantation with relative safety.