Complications: skull base and cerebrovascular.

Neurosurgical complications are a rich source for learning, but they are grossly underutilized for the purpose of surgeon education. Details of the complications, which make them all the more powerful as teaching tools, are restricted to morbidity and mortality conferences behind closed doors, and open discussions of the topic are blurred by hypotheticals in order to shield the presenters from medicolegal risks. In this issue of Neurosurgical Focus, 9 neurosurgeons were invited to present complications they encountered along with the details and specific lessons they learned.

Skull Base Training and Mentorship.

Objective: To review teaching and mentoring techniques of experienced skull base surgeons and educators STUDY DESIGN:: Expert commentary.

Setting: 8th Quadrennial International Conference on vestibular schwannoma and other CPA tumors, panel on teaching, and mentoring.

Main Outcome Measures: Experiences and opinions of experienced skull base surgeons, both neurosurgeons and neurotologists, presented and discussed at the conference.

Retrosigmoid Transtentorial Approach Compared to Traditional Transpetrosal Approaches for the Resection of Petroclival Meningiomas: A Case-Control Study.

 Transpetrosal approaches have become standard technique for resection of petroclival meningiomas (PCM). The retrosigmoid craniotomy has also been extensively studied as an alternative approach. The need to resect the tentorium at the end of a retrosigmoid approach has been described, but the upfront transtentorial variation of the retrosigmoid craniotomy has never been described nor evaluated in detail as a possible alternative to the standard petrosectomy approaches.

Human Bone Marrow Endothelial Progenitor Cell Transplantation into Symptomatic ALS Mice Delays Disease Progression and Increases Motor Neuron Survival by Repairing Blood-Spinal Cord Barrier.

Convincing evidence demonstrated impairment of the blood-spinal cord barrier (BSCB) in Amyotrophic Lateral Sclerosis (ALS), mainly by endothelial cell (EC) alterations. Replacing damaged ECs by cell transplantation is a potential barrier repair strategy. Recently, we showed that intravenous (iv) administration of human bone marrow CD34 (hBM34) cells into symptomatic ALS mice benefits BSCB restoration and postpones disease progression.

Successful Microvascular Decompression For Trigeminal Neuralgia Secondary to a Persistent Trigeminal Artery.

Background And Importance: Persistent trigeminal artery (PTA) is a rare but important anatomic variant that contributes to trigeminal neuralgia (TN). Microvascular decompression (MVD) of the responsible vessel(s) away from the trigeminal nerve provides the most complete and durable relief from TN. The role and technique of MVD for TN associated with a PTA has not been fully defined in the literature.

A Pivotal Randomized Clinical Trial Evaluating the Safety and Effectiveness of a Novel Hydrogel Dural Sealant as an Adjunct to Dural Repair.

Background: A watertight dural repair is critical to minimizing the risk of postoperative complications secondary to cerebrospinal fluid (CSF) leaks.

Objective: To evaluate the safety and efficacy of a novel hydrogel, Adherus Dural Sealant, when compared with control, DuraSeal Dural Sealant System, as an adjunct to standard methods of dural repair.

Methods: In this 17-center, prospective, randomized clinical trial designed as a noninferiority, single-blinded study, 124 patients received Adherus Dural Sealant (test sealant) and 126 received DuraSeal (control).

Denervation of the Eustachian Tube and Hearing Loss Following Trigeminal Schwannoma Resection.

Objectives To discuss eustachian tube dysfunction (ETD) as a cause of hearing loss and to discuss its pathogenesis following resection of trigeminal schwannomas. Methods Presented herein are two cases of trigeminal schwannoma that were resected surgically with sacrifice of the motor branch of the trigeminal nerve. Neither of the cases had evidence of extracranial extension nor preoperative ETD.

Anterior Petrosectomy: Consecutive Series of 46 Patients with Attention to Approach-Related Complications.

Objective Anterior petrosectomy(AP) was popularized in the 1980s and 1990s as micro-neurosurgery proliferated. Original reports concentrated on the anatomy of the approach and small case series. Recently, with the advent of additional endonasal approaches to the petrous apex, the morbidity of AP remains unclear.

Junctional Internal Carotid Artery Aneurysms: The Schrödinger's Cat of Vascular Neurosurgery.

Objectives Despite advances in neuroimaging, it is not always definitive whether a paraclinoid aneurysm is intradural or entirely extradural. We illustrate the potential use of surgical exploration in these aneurysms that we refer to as "junctional" aneurysms. Methods Retrospective review of eight patients with unruptured aneurysms who underwent a planned surgical exploration of a junctional aneurysm.

C-shaped Incision for Far-Lateral Suboccipital Approach: Anatomical Study and Clinical Correlation.

Background The standard incision for far-lateral suboccipital approaches has been the classic "reverse hockey stick." Although that incision provides ample exposure, concern has been raised that excessive muscle dissection and skin elevation might lead to accumulation of cerebrospinal fluid (CSF) under the flap with increased risk of CSF leak. We hypothesize that the C-shaped incision can minimize the amount of muscle dissection and provide optimal exposure and surgical outcomes.

Anterior inferior petrosectomy: defining the role of endonasal endoscopic techniques for petrous apex approaches.

Object: Historically, surgery to the petrous apex has been addressed via craniotomy and open microscopic anterior petrosectomy (OAP). However, with the popularization of endoscopic approaches, the petrous apex can further be approached endonasally by way of an endoscopic endonasal anterior petrosectomy (EAP). Endonasal anterior petrosectomy is a relatively new procedure and has not been compared anatomically with OAP.

Combined subgaleal/myocutaneous technique for temporalis muscle dissection.

Background The frontal branch of the facial nerve (FBFN) is the most susceptible neural structure to injury during frontotemporal craniotomies. The balance between adequate temporalis muscle mobilization and frontal branch protection with minimal anatomical alteration is the philosophy behind our approach to temporalis muscle dissection. Objective To describe a combined subgaleal/myocutaneous technique for dissection and mobilization of the temporalis muscle in anterolateral cranial approaches.

Epidemiological survey-based formulae to approximate incidence and prevalence of neurological disorders in the United States: a meta-analysis.

Background: This study aims to create a convenient reference for both clinicians and researchers so that vis-à-vis comparisons between brain disorders can be made quickly and accurately. We report here the incidence and prevalence of the major adult-onset brain disorders in the United States using a meta-analysis approach.

Material And Methods: Epidemiological figures were collected from the most recent, reliable data available in the research literature.

Acoustic neuroma observation associated with an increase in symptomatic tinnitus: results of the 2007-2008 Acoustic Neuroma Association survey.

Object: Tinnitus is a known presenting symptom of acoustic neuromas, but little is known about the impact of observation or treatment on tinnitus. Most patients experience improvement with treatment, while others may worsen. Therefore, this study was designed to assess the overall impact of observation and treatment on tinnitus outcome in patients with acoustic tumors.

Field of view comparison between two-dimensional and three-dimensional endoscopy.

Objectives/hypothesis: Relative to microscopic transnasal surgery, endoscopic surgery provides improved visualization with an increased field of view. Advances such as high-definition (HD) and three-dimensional (3D) endoscopy have been introduced and clearly improve visualization. However, do both technologies maintain an increased field of view? We hypothesize that the field of view of 3D endoscopy is restricted relative to two-dimensional (2D) HD endoscopy.

Catheter fixation and ligation: a simple technique for ventriculostomy management following endovascular stenting.

The object of this study was to describe a unique method of managing ventriculostomy catheters in patients on antithrombotic therapy following endovascular treatment of ruptured intracranial aneurysms. The authors retrospectively reviewed 3 cases in which a unique method of ventriculostomy management was used to successfully avoid catheter-related hemorrhage while the patient was on dual antiplatelet therapy. In this setting, ventriculostomy catheters are left in place and fixed to the calvarium with titanium straps effectively ligating them.

Paradoxical trends in the management of vestibular schwannoma in the United States.

Object: Recent natural history studies of vestibular schwannomas (VSs) suggest that most of these tumors do not grow. The impact of these new data on management trends in the US is currently unknown. The aim in the present study was to evaluate current trends in the treatment of VS in the US by analyzing a national cancer database.

A multicenter, single-blind, prospective randomized trial to evaluate the safety of a polyethylene glycol hydrogel (Duraseal Dural Sealant System) as a dural sealant in cranial surgery.

Objective: Incisional cerebrospinal fluid (CSF) leakage after cranial surgery is a significant cause of morbidity due to poor wound healing and infection, meningitis, and pseudomeningocele formation. Many common dural closure techniques, such as sutures, autologous grafts, gelatin or collagen sponges, and fibrin glues, are used to achieve watertight closure, although none are US Food and Drug Administration approved for this use. DuraSeal Dural Sealant System is a polyethylene glycol (PEG) hydrogel approved by the U.

Paradoxical trends in the management of unruptured cerebral aneurysms in the United States: analysis of nationwide database over a 10-year period.

Background And Purpose: The objective of this study was to characterize demographics, treatments, and outcomes in the management of unruptured cerebral aneurysms in the United States using a national healthcare database.

Methods: Clinical data were derived from the Nationwide Inpatient Sample for the years 1997 through 2006. Patients with unruptured cerebral aneurysms were identified using the appropriate International Classification of Diseases, 9th Revision code (437.

Life without the vein of Galen: Clinical and radiographic sequelae.

A thorough understanding of the anatomy of the pineal region, particularly venous drainage, is critical for gaining open surgical access to the pineal gland. The adverse sequelae after intraoperative venous occlusion are assumed to be catastrophic but have been scarcely reported. We report a case of pineocytoma in which the vein of Galen was ligated without postoperative adverse sequelae.

The anterolateral approach for the transcranial resection of pituitary adenomas: technical note.

We sought to quantify the mean surface area of the exposed diaphragma sellae and the mean sellar volume in the subfrontal and anterolateral approaches to pituitary adenomas and to detail our expansion of the superficial and deep window in the anterolateral approach. We performed a retrospective data analysis and cadaveric study in a clinical and skull base laboratory. We studied eight patients who had anterolateral approach for transcranial resection of pituitary macroadenoma and seven cadaveric specimens.

Management of the great mimicker: Meckel cave tumors.

Background: Meckel cave tumors are often asymptomatic and have a sufficiently characteristic magnetic resonance imaging/computed tomography signature that allows treatment/surveillance decisions to be made without biopsy confirmation. Radiographic diagnosis requires the surgeon to be fully aware of the plethora of unusual Meckel cave lesions that mimic benign tumors when they are malignant, inflammatory, or infectious and in need of a completely different and often timely intervention. When such a diagnosis is considered, it behooves the surgeon and benefits the patient to have a percutaneous biopsy technique available.

Posterior clinoidectomy: dural tailoring technique and clinical application.

The posterior clinoid process, a bony prominence at the superolateral aspect of the dorsum sellae, has a strategic importance in a transcavernous approach to basilar tip aneurysms. To further optimize this microsurgical technique during posterior clinoidectomy, we performed a cadaveric study of this regional anatomy, describe a technique called dural tailoring, and report initial results in the surgical treatment of upper basilar artery (BA) aneurysm. After 10 adult cadaver heads (silicone-injected) were prepared for dissection, a posterior clinoidectomy with dural tailoring was performed.