The Evolving Paradigm in the Management of Intracranial Atherosclerotic Disease

Intracranial atherosclerotic disease (ICAD) is a major cause of ischemic stroke worldwide and represents a significant health problem. The pathogenesis and natural history of ICAD are poorly understood, and rigorous treatment paradigms do not exist as they do for extracranial atherosclerosis. Currently, the best treatment for ICAD remains aspirin therapy, but many patients who are placed on aspirin continue to experience recurrent strokes. As microsurgical and endovascular techniques continue to evolve, the role of extracranial to intracranial bypass operations and stenting are increasingly being reconsidered. We performed a PubMed review of the English literature with a particular focus on treatment options for ICAD and present evidence-based data for the role of surgery and stenting in ICAD against medical therapy alone

Trends in Intracranial Stenting Among Medicare Beneficiaries in the United States, 2006–2010

Background: It is uncertain how intracranial stenting (ICS) has been adopted nationally during a period characterized by a restrictive payment policy by the Centers for Medicare & Medicaid Services, humanitarian device exemption approval by the Food and Drug Administration, and insufficient evidence of effectiveness. We sought to determine the trends in rates of ICS use and associated outcomes in the United States. Methods and Results: From 65 211 328 Medicare Fee‐for‐Service beneficiaries hospitalized between 2006 and 2010 in acute care hospitals in the United States, we included patients with ICD‐9‐CM procedure codes for intracranial angioplasty and stenting, excluding those with a principal discharge diagnosis code of cerebral aneurysm or subarachnoid hemorrhage. We report operative rates per 1 000 000 person‐years and outcomes including 30‐day and 1‐year mortality rates. There were 838 ICS procedures performed among Fee‐for‐Service beneficiaries. The overall hospitalization rate for ICS increased significantly from ≈1 per 1 000 000 person‐years (n=35 procedures) in 2006 to 9 per 1 000 000 person‐years (n=258 procedures) in 2010 (P=0.0090 for trend). Procedure rates were higher in men than in women, and were highest among patients aged 75 to 84 years and lowest among those ≥85 years. The 30‐day mortality rate increased from 2.9% (95% CI, 0.1 to 15.3) to 12.9% (95% CI, 9.0 to 17.6), P=0.1294 for trend, and the 1‐year mortality rate increased from 14.7% (95% CI, 5.0 to 31.1) to 19.5% (95% CI, 14.9 to 24.9), P=0.0101; however, the annual changes were not significant after adjustment. Conclusions: ICS utilization in the United States has modestly increased during a period of inadequate supportive evidence. Humanitarian device exemption and a restrictive payment policy appear to have caused slow adoption of the technology

Results of an international survey on the investigation and endovascular management of cerebral vasospasm and delayed cerebral ischemia

Background: Delayed cerebral ischemia (DCI) is a major cause of morbidity and mortality in aneurysmal subarachnoid hemorrhage. Endovascular management of this condition offers a new hope in preventing adverse outcome; however, a uniform standard of practice is lacking owing to a paucity of clinical trials. We conducted an international survey on the use of investigative and endovascular techniques in the treatment of DCI to assess the variability of current practice. Methods: Neurovascular neurosurgeons and neuroradiologists were contacted through professional societies from America, United Kingdom, Europe, and Australasia. Members were invited to complete a 13-item questionnaire regarding screening techniques, first-line and second-line therapies in endovascular intervention, and the role of angioplasty. Answers were compared using χ2 testing for nonparametric data. Results: Data from 344 respondents from 32 countries were analyzed: 167 non-United States and 177 U.S. respondents. More than half of all clinicians had 10+ years of experience in units with a mixture of higher and lower case volumes. Daily transcranial Doppler ultrasonography was the most commonly used screening technique by both U.S. (70%) and non-U.S. (53%) practitioners. Verapamil was the most common first-line therapy in the United States, whereas nimodipine was most popular in non-U.S. countries. Angioplasty was performed by 83% of non-U.S. and 91% of U.S. clinicians in the treatment of vasospasm; however, more U.S. clinicians reported using angioplasty for distal vasospasm. Conclusions: Treatment practices for DCI vary considerably, with the greatest variability in the choice of agent for intra-arterial therapy. Our data demonstrate the wide variation of approaches in use at present. However, without further clinical trials and development of a uniform standard of best practice, variability in treatment and outcome for DCI is likely to continue

Hemifacial Spasm and Neurovascular Compression

Hemifacial spasm (HFS) is characterized by involuntary unilateral contractions of the muscles innervated by the ipsilateral facial nerve, usually starting around the eyes before progressing inferiorly to the cheek, mouth, and neck. Its prevalence is 9.8 per 100,000 persons with an average age of onset of 44 years. The accepted pathophysiology of HFS suggests that it is a disease process of the nerve root entry zone of the facial nerve. HFS can be divided into two types: primary and secondary. Primary HFS is triggered by vascular compression whereas secondary HFS comprises all other causes of facial nerve damage. Clinical examination and imaging modalities such as electromyography (EMG) and magnetic resonance imaging (MRI) are useful to differentiate HFS from other facial movement disorders and for intraoperative planning. The standard medical management for HFS is botulinum neurotoxin (BoNT) injections, which provides low-risk but limited symptomatic relief. The only curative treatment for HFS is microvascular decompression (MVD), a surgical intervention that provides lasting symptomatic relief by reducing compression of the facial nerve root. With a low rate of complications such as hearing loss, MVD remains the treatment of choice for HFS patients as intraoperative technique and monitoring continue to improve

Failure of the Pipeline Embolization Device in Posterior Communicating Artery Aneurysms Associated with a Fetal Posterior Cerebral Artery

The pipeline embolization device has emerged as an important endovascular option. This is in part due to safety, efficacy, and possibly the ability to shorten the operative time considerably. With this new technology, some limitations are emerging as experience accumulates. We report three cases of posterior communicating (PCOM) artery aneurysms associated with fetal posterior cerebral artery where pipeline embolization was unsuccessful in obliterating the aneurysms. PCOM artery aneurysms associated with a fetal PCA should be managed either by microsurgical clipping or coiling when feasible

Assessing the Efficacy of Commercially Available Filters in Removing Air Micro-Emboli in Intravenous Infusion Systems

The presence of gaseous air emboli in the vasculature has the potential to cause significant morbidity and mortality. Once viewed as a rare complication of high-risk surgeries, air embolism is now also being associated with even minor and routine procedures such as peripheral venous catheterization. With increasing recognition, various preventive measures have emerged, the most important of which is the use of air-eliminating filters. However, studies on these devices are currently lacking. Therefore, in this present study, we aimed to evaluate the effectiveness of two commercially available filters in removing air within intravenous (IV) lines. An IV infusion system was created, designed to resemble standard conditions used in real clinical practice. Testing was completed using a .9% NaCl solution at room temperature with a flow rate set at 75 mL/h and involving three different filter orientations. The test bed was configured to inject air every 2 minutes with volumes ranging between 5 and 600 μL. The two filter models tested were GVS .2-μM and Braun SUPOR membrane air-eliminating filters. Data was collected at pre-filter and post-filter sites. The Braun SUPOR membrane filter (B Braun, Bethlehem, PA) reduced air micro-emboli by 100.0% (p < .0001) both by volume and count compared with −.6 ± 3.5% by volume and −.8 ± 1.5% by count for the control. The reduction seen with the GVS .2-μM filter was 99.8 ± .2% (p < .0001) by volume and 86.2 ± 21.1% (p < .0001) by count compared with the control. There was no statistically significant difference in the removal efficacy between the two filter models. As the use of air-eliminating filters becomes a common standard of care, establishing the validity of the commercially available filter models is important to minimize the risk of vascular air embolism

Surgery for Petroclival Meningiomas: A Comprehensive Review of Outcomes in the Skull Base Surgery Era

Skull base surgery has evolved to a point that its focus is now shifting to outcome analysis. To do so for petroclival meningiomas is difficult. The rarity of the tumor, different treatment philosophies, and variations in reporting complicate the outcome analysis. With this limitation in mind, we analyzed the literature on this disease and report the combined outcomes in a unified fashion in hopes that it will serve as a starting point for further prospective analysis. Data was extracted from all available reports on MEDLINE/PubMed published in English. All studies were retrospective and uncontrolled. The majority of studies represent the experience of a single surgeon at a single institution. Of the 19 studies with detailed demographic and outcome data, no data met criteria for meta-analysis. A total of 1000 patients were reported. The mean age of the patients was 50 years. The male to female ratio is 1:3. GTR (gross total resection) was reported in 49% of patients. Thirty-four percent of patients experienced some neurological deficit in the early postoperative period (<3 months). The most common morbidities reported were cranial nerve deficits (34.4% [range: 20 to 79%]) with facial nerve injury accounting for 19%, followed by motor deficits (14%), infection rates (1.6%), CSF leaks (5%), hemorrhage (1.2%), and hydrocephalus (1%). Death within 1 year of surgery was reported for 1.4% of patients. Once considered untreatable, petroclival meningiomas can now be approached relatively safely. There, however, still remains an ∼34% morbidity with the most common being cranial nerve. Despite this, >75% of patients return to independence at 1 year, many of which will resume employment. The nature of this study limits the conclusions that can be drawn; however, it provides some generalizations that may help guide patient questions regarding treatment outcomes

Case Report - Association between pituitary adenomas and intracranial aneurysms: An illustrative case and review of the literature

The co-existence of cerebral aneurysms and pituitary adenomas is rare. Here, we report a patient with a coexisting anterior communicating artery aneurysm and a pituitary adenoma and review the available literature concerning this phenomenon. There is a debate in the literature regarding any causal relationship between aneurysms and pituitary tumors, although there are many reports of aneurysms caused by trauma or radiation following treatment of pituitary tumors. These simultaneous lesions are best diagnosed with magnetic resonance imaging with magnetic resonance angiography. Craniotomy for simultaneous aneurysm clipping and resection of the pituitary tumor is the best treatment option

Landscape of genetic variants in sporadic meningiomas captured with clinical genomics.

BACKGROUND: Meningiomas are the most common primary central nervous system tumor. Previous studies have characterized recurrent genetic alterations that can predict patient prognosis and potentially provide new avenues for therapeutic intervention. Continued efforts to characterize the genomic changes in meningioma samples can aid in the discovery of therapeutic targets and appropriate patient stratification. METHODS: We performed targeted genomic sequencing on 25 primary and 2 recurrent meningiomas using a 500-gene panel, including canonical meningioma drivers. We further detail the genomic profiles and relevant clinical findings in three cases of angiomatous meningiomas and two recurrent atypical meningiomas. RESULTS: Our approach uncovers a diverse landscape of genomic variants in meningioma samples including mutations in established meningioma-related genes NF2, AKT1, PIK3CA, and TRAF7. In addition to known meningioma drivers, we uncover variants in genes encoding other PI3K subunits, Notch/hedgehog/Wnt signaling pathway components, and chromatin regulators. We additionally identify 22 genes mutated across multiple samples. Three patients included in the study were diagnosed with angiomatous WHO grade I meningiomas, all three of which contained variants in the PI3K-AKT signaling pathway previously described to regulate tumor angiogenesis. Analysis of patient-matched primary and recurrent atypical meningiomas revealed clonal enrichment for mutations in the SWI/SNF complex subunits ARID1A and SMARCA4. CONCLUSIONS: Targeted genomics implemented in neuro-oncology care can enhance our understanding of the genetic underpinnings of central nervous system tumors, including meningiomas. These molecular signatures may be clinically useful in dictating treatment strategies and patient follow-up