Response to Preoperative Dexamethasone Predicts Postoperative Neurological Improvement of Focal Neurological Deficits in Patients With Brain Metastases.

Background: Steroids are used ubiquitously in the preoperative management of patients with brain tumor. The rate of improvement in focal deficits with steroids and the prognostic value of such a response are not known.

Objective: To determine the rate at which focal neurological deficits respond to preoperative corticosteroids in patients with brain metastases and whether such an improvement could predict long-term recovery of neurological function after surgery.

Innovative growth and development of a neurological surgery residency cadaveric skull base simulation training program: A single institution experience.

Objective: Neurosurgical cadaveric and simulation training is a valuable opportunity for residents and fellows to develop as neurosurgeons, further neuroanatomy knowledge, and develop decision-making and technical expertise. The authors describe the growth and development of Oregon Health & Science University (OHSU) Department of Neurological Surgery (NSG) resident hands-on simulation skull base course and provide details of course layout and setup.

Methods: A three-part surgical simulation series was created to provide training in cadaveric skull base procedures.

Fluid dynamics in aging-related dementias.

Recent human and animal model experimental studies revealed novel pathways for fluid movement, immune cell trafficking and metabolic waste clearance in CNS. These studies raise the intriguing possibility that the newly discovered pathways, including the glymphatic system, lymphatic meningeal vessels and skull-brain communication channels, are impaired in aging and neurovascular and neurodegenerative diseases associated with dementia, including Alzheimer's disease (AD) and AD-related dementia. We provide an overview of the glymphatic and dural meningeal lymphatic systems, review current methods and approaches used to study glymphatic flow in humans and animals, and discuss current evidence and controversies related to its role in CNS flow homeostasis under physiological and pathophysiological conditions.

A technical note on anterolateral mobilization in vertebrobasilar dolichoectasia for relief of brainstem compression.

Vascular compression of neural tissue causing neurological symptoms is a wellknown phenomenon. This is commonly seen in trigeminal neuralgia and, less commonly, in hemifacial spasm by small arteries, which can be treated by microvascular decompression. Rarely, larger arteries, such as the vertebral arteries, may compress the brainstem.

Endoscopic Endonasal Eustachian Tube Obliteration as a Treatment for Tension Pneumocephalus After Translabyrinthine Resection of Vestibular Schwannoma.

Objective: Cerebrospinal fluid leak and pneumocephalus are rare but potentially devastating complications associated with translabyrinthine resection of cerebellopontine angle masses. Persistent pneumocephalus despite proximal eustachian tube (ET) obliteration is rare. We describe, to our knowledge, the first report of successful management of tension pneumocephalus by endoscopic endonasal ET obliteration using a novel V-loc (Covidien; Medtronic, Minneapolis, MN) suture technique.

Endoscopic Endonasal Eustachian Tube Obliteration for Cerebrospinal Fluid Rhinorrhea: A Case Series and Scoping Review.

Background: Endoscopic endonasal eustachian tube obliteration (EEETO) is a valuable option for treating cerebrospinal fluid rhinorrhea (CSFR) after lateral skull base surgery. Several small case series describe different techniques because of the rarity of this indication.

Objective: To review available literature on EEETO focusing on technique and factors affecting success.

Regression of Multiple Meningiomas after Discontinuation of Chronic Hormone Therapy: A Case Report.

 Meningiomas are more common in females and frequently express progesterone and estrogen receptors. Recent studies have revealed a high incidence of meningiomas in situations in which estrogen/progesterone levels are increased such as pregnancy, gender reassignment therapy, and fertility treatment. While the relationship remains unclear and controversial, these findings suggest exposure to high levels of endogenous or exogenous hormones may increase the risk of developing a meningioma.

A Double-Blind, Randomized, Placebo-Controlled Trial of Soluble Epoxide Hydrolase Inhibition in Patients with Aneurysmal Subarachnoid Hemorrhage.

Background: Epoxyeicosatrienoates (EETs) are endogenous regulators of neuroinflammation and cerebral blood flow. Their metabolism to dihydroxyeicosatrienoates (DHETs) is catalyzed by soluble epoxide hydrolase (sEH). After subarachnoid hemorrhage (SAH), EETs' pathway amplification may be a therapeutic target for the prevention of delayed cerebral ischemia (DCI).

Determinants of survival in sinonasal and skull base chondrosarcoma: An analysis of the National Cancer Database.

Background: Chondrosarcomas are rare, malignant chondroid tumors that can occur in the sinonasal and skull base regions. Surgery is a mainstay of treatment, but complete resection can be challenging because of the close proximity of critical neurovascular structures. Because of their rarity and relatively indolent nature, optimal treatment regimens are not established.

Development of a Cadaveric Multiport Model of Posterior Circulation Aneurysm Clipping for Neurosurgery and Otolaryngology Residents.

Posterior circulation aneurysms are difficult to treat with the current methods of coiling and clipping. To address limitations in training, we developed a cadaveric model to train learners on endoscopic clipping of posterior circulation aneurysms. An endoscopic transclival approach (ETA) and a transorbital precaruncular approach (TOPA) to successfully access and clip aneurysms of the posterior circulation are described.

Opioid use after endoscopic skull base surgery: A descriptive, prospective, longitudinal cohort study.

Background: Opioid abuse is a public health crisis and the perioperative period can be a time of first opioid exposure. Little is known about postoperative pain management after endoscopic skull base surgery (ESBS).

Methods: This investigation was a single-institution, longitudinal, prospective cohort study of adult patients undergoing ESBS between November 2019 and March 2020.

Echocardiographic findings in acromegaly: prevalence of concentric left ventricular remodeling in a large single-center cohort.

Purpose: Acromegaly is a rare disease and is associated with increased cardiovascular (CV) morbidity and mortality, especially in patients with uncontrolled disease. We aimed to analyze the prevalence and severity of cardiomyopathy and valvular heart disease in a large cohort of patients with a confirmed acromegaly diagnosis, at baseline and after treatment.

Methods: We retrospectively reviewed an institutional approved database; 190 patients with confirmed acromegaly and follow-up data available (years 2006-2018).

In a model of SAH-induced neurogenic fever, BAT thermogenesis is mediated by erythrocytes and blocked by agonism of adenosine A1 receptors.

Neurogenic fever (NF) after subarachnoid hemorrhage (SAH) is a major cause of morbidity that is associated with poor outcomes and prolonged stay in the neurointensive care unit (NICU). Though SAH is a much more common cause of fever than sepsis in the NICU, it is often a diagnosis of exclusion, requiring significant effort to rule out an infectious source. NF does not respond to standard anti-pyretic medications such as COX inhibitors, and lack of good medical therapy has led to the introduction of external cooling systems that have their own associated problems.

Changing Hands: A Rising Role of the Tumor Surgeon in Teaching Sylvian Fissure Dissection.

Objective: The landscape of microneurosurgery has changed considerably over the past 2 decades, with a decline in indications for open surgery on cerebrovascular pathology and ever-increasing indications for open resection of brain tumors. This study investigated how these trends in case volume affected residents' training experiences in microsurgery and, specifically, Sylvian fissure dissection.

Methods: Resident case logs were reviewed, identifying open cerebrovascular operations and craniotomies for tumor.

Cystic appearance on magnetic resonance imaging in bihormonal growth hormone and prolactin tumors in acromegaly.

Purpose: To investigate demographic, imaging and laboratory characteristics, and treatment outcomes of acromegaly patients who have bihormonal (BA) growth hormone (GH) and prolactin (PRL) immunoreactive adenomas compared to patients who have densely granulated GH adenomas (DGA) and sparsely granulated GH adenomas (SGA).

Methods: Retrospective review of single-center surgically treated acromegaly patients; pathology was analyzed by a single neuropathologist using 2017 WHO criteria. Preoperative magnetic resonance imaging was assessed to evaluate tumor size, cystic component, invasion and T2 signal intensity.

Pituitary society guidance: pituitary disease management and patient care recommendations during the COVID-19 pandemic-an international perspective.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the viral strain that has caused the coronavirus disease 2019 (COVID-19) pandemic, has presented healthcare systems around the world with an unprecedented challenge. In locations with significant rates of viral transmission, social distancing measures and enforced 'lockdowns' are the new 'norm' as governments try to prevent healthcare services from being overwhelmed. However, with these measures have come important challenges for the delivery of existing services for other diseases and conditions.

Distinguishing Extravascular from Intravascular Ferumoxytol Pools within the Brain: Proof of Concept in Patients with Treated Glioblastoma.

Background And Purpose: Glioblastoma-associated macrophages are a major constituent of the immune response to therapy and are known to engulf the iron-based MR imaging contrast agent, ferumoxytol. Current ferumoxytol MR imaging techniques for localizing macrophages are confounded by contaminating intravascular signal. The aim of this study was to assess the utility of a newly developed MR imaging technique, segregation and extravascular localization of ferumoxytol imaging, for differentiating extravascular-from-intravascular ferumoxytol contrast signal at a delayed 24-hour imaging time point.

Dural Arteriovenous Fistula Presenting as Trigeminal Neuralgia: 2 Case Reports and Review of the Literature.

Background: Dural arteriovenous fistulae (dAVFs) can sporadically compress the root entry zone of the trigeminal nerve or the Gasserian ganglion and therefore be a rare cause of isolated or complicated trigeminal neuralgia (TN).

Case Description: We describe 2 cases of TN related to dAVF treated similarly with transarterial embolization but with divergent outcomes. Further, we completed a comprehensive literature review of previously reported cases to date.

Hypercoagulability in Cushing Syndrome, Prevalence of Thrombotic Events: A Large, Single-Center, Retrospective Study.

Background: The risk of Cushing syndrome (CS) patients experiencing a thrombotic event (TE) is significantly higher (odds ratio; OR 18%) than that of the general population. However, there are currently no anticoagulation guidelines.

Methods: A retrospective, single-center, longitudinal study of patients undergoing all types of treatment-surgical (pituitary, unilateral, and bilateral adrenalectomy) and medical treatment-was undertaken.

External retrospective validation of Brain Injury Guidelines criteria and modified guidelines for improved care value in the management of patients with low-risk neurotrauma.

Objective: Conventional management of patients with neurotrauma frequently consists of routine, repeat head CT at preordained intervals with ICU-level monitoring, regardless of injury severity. The Brain Injury Guidelines (BIG) are a classification tool for stratifying patients into injury severity and risk-of-progression categories based on presenting clinical and radiographic findings. In the present study, the authors aimed to validate BIG criteria at a single level 1 trauma center.

Arteriovenous Malformation Presenting as Symptomatic, Enlarging and Contrast-Enhancing Mass 12 Years After Being Treated with Embolization and Radiotherapy.

Background: Gross total resection of arteriovenous malformations (AVMs) of the central nervous system confirmed by formal angiography is accepted as a cure for patients. In some cases, this may not be possible. Even though in these cases other treatment modalities such as endovascular embolization and radiotherapy can be used, long-term follow-up is lacking in the literature.

Subarachnoid Hemorrhage Pattern Predicts Acute Cerebral Blood Flow Response in the Rat.

There is considerable variability in the presentation of patients with acute subarachnoid hemorrhage (aSAH). Evidence suggests that a thick, diffuse clot better predicts the development of delayed cerebral ischemia and poor outcomes. In a rodent model of acute SAH, we directly measured the effects of the volume of blood injected versus the pattern of distribution of hemorrhage in the subarachnoid space on markers of early brain injury, namely, cerebral blood flow (CBF), cerebrospinal fluid (CSF) concentrations of P450 eicosanoids and catecholamines, and cortical spreading depolarizations (CSDs).

Medial axis segmentation of cranial nerves using shape statistics-aware discrete deformable models.

Purpose: We propose a segmentation methodology for brainstem cranial nerves using statistical shape model (SSM)-based deformable 3D contours from T MR images.

Methods: We create shape models for ten pairs of cranial nerves. High-resolution T MR images are segmented for nerve centerline using a 1-Simplex discrete deformable 3D contour model.