Maturation of the sella turcica and parasellar region: Surgical relevance for anterior skull base approaches in pediatric patients.

Objective: Traditional and extended transnasal transsphenoidal approaches provide direct access to a variety of anterior skull base pathologies. Despite increased utilization of transnasal approaches in children, anatomic studies on pediatric skull base maturation are limited. We herein perform a surgically relevant morphometric analysis of the sella and parasellar regions during pediatric maturation.

Maturation of the internal auditory canal and posterior petrous bone with relevance to lateral and posterolateral skull base approaches.

Anatomic knowledge of the internal auditory canal (IAC) and surrounding structures is a prerequisite for performing skull base approaches to the IAC. We herein perform a morphometric analysis of the IAC and surgically relevant aspects of the posterior petrous bone during pediatric maturation, a region well-studied in adults but not children. Measurements of IAC length (IAC-L), porus (IAC-D) and midpoint (IAC-DM) diameter, and distance from the porus to the common crus (CC; P-CC) and posterior petrosal surface (PPS) to the posterior semicircular canal (PSC; PPS-PSC) were made on thin-cut axial CT scans from 60 patients (grouped by ages 0-3, 4-7, 8-11 12-15, 16-18, and > 18 years).

Gross Total Resection of a Recurrent Cavernous Sinus Meningioma through a Combined Transzygomatic Transcavernous and Extended Middle Fossa Approach with Cavernous Carotid Denudation.

 The aim of this study is to describe surgical management of invasive cavernous sinus meningioma with a combination of skull base approaches.  This study is an operative video.  Resection of the recurrent skull base meningioma is still challenging, especially if the tumor involves or encases the carotid artery.

Petroclival meningiomas: update of current treatment and consensus by the EANS skull base section.

Background: The optimal management of petroclival meningiomas (PCMs) continues to be debated along with several controversies that persist.

Methods: A task force was created by the EANS skull base section along with its members and other renowned experts in the field to generate recommendations for the management of these tumors. To achieve this, the task force reviewed in detail the literature in this field and had formal discussions within the group.

Gross Total Resection of a Recurrent in-and-around Cavernous Sinus Meningioma through a Combined Transcavernous Anterior and Middle Infratemporal Fossa Approach with Extracranial-Intracranial Bypass.

 The study aims to describe surgical management of an invasive cavernous sinus meningioma with a combination of several skull base approaches and bypass surgery.  This study is an operative video.  Resection of the recurrent skull base meningioma is still challenging, especially if the tumor involves or encases the carotid artery.

Extended Middle Cranial Fossa Approach for Lesions Invading Infratemporal Fossa: Anatomic Study and Clinical Application.

Skull base tumors arising from the middle cranial fossa and invading of the infratemporal fossa (ITF) and middle cranial fossa are challenging for neurosurgeons, because of complex anatomy and critical neurovascular structure involvement. The first pioneering ITF approaches resulted in invasive procedures and carried a high rate of surgical morbidity. However, the acquisition of deep anatomical knowledge, and the development operative skills and reconstruction techniques allowed surgeons to achieve total or near total resection of many ITF lesions with a low morbidity rate.

Micropatties Are Indispensable Instruments for Successful Microneurosurgery: Technical Note.

Background: Neurosurgical micropatties (also known as sponges or cottonoids) have been used in microsurgical procedures to protect the brain surface and aspirate cerebrospinal fluid and blood. We sought to describe unique applications of micropatties in neurosurgical interventions.

Methods: Various sizes of micropatties have been used in neurosurgical interventions including tumor, vascular, and skull base surgeries to enhance safe surgical procedures and clear the operative field.

Wedge-technique for transposition of the vertebral artery in microvascular decompression for hemifacial spasm: technical nuances and surgical outcomes.

Background: Transposition of the vertebral artery (VA) for microvascular decompression for hemifacial spasm (HFS) is often challenging. Various procedures have been proposed to transpose the immobile tortuous VA that cannot be decompressed satisfactorily in the usual manner.

Methods: A Teflon piece that is cut into a wedge shape was used for transposition of the VA as an offending artery in HFS.

Microsurgical resection of vestibular schwannomas: complication avoidance.

Vestibular schwannoma (VS) surgery requires appropriate patient selection, meticulous microsurgical technique and optimal post-operative care. Focused radiation is an effective alternative for the treatment of smaller VSs. For VS surgery to remain a reasonable option, surgery must be performed with a limited number of complications.

Underlay hourglass-shaped autologous pericranium duraplasty in "key-hole" retrosigmoid approach surgery: Technical report.

Background: Cerebrospinal fluid (CSF) leakages represent a major complication of skull base surgery. Watertight dural suture is challenging, and different ways to reinforce it have been proposed. Since 6 months, we use locally harvested autologous pericranium graft for dural repair in retrosigmoid approach.

Surgical management of vestibular schwannomas after failed radiation treatment.

Increasing numbers of patients with vestibular schwannoma (VS) have been treated with focused-beam stereotactic radiation treatment (SRT) including Gamma knife, CyberKnife, X-knife, Novalis, or proton beam therapy. The purpose of this study was to document the incidence of tumor regrowth or symptoms that worsened or first developed following SRT and to discuss surgical strategies for patients who have failed SRT for VS. A consecutive series of 39 patients with SRT failed VS were surgically treated.

Middle infratemporal fossa less invasive approach for radical resection of parapharyngeal tumors: surgical microanatomy and clinical application.

Surgery of the infratemporal fossa (ITF) and parapharyngeal area presents a formidable challenge to the surgeon due to its anatomical complexity and limited access. Conventional surgical approaches to these regions were often too invasive and necessitate sacrifice of normal function and anatomy. To describe a less invasive transcranial extradural approach to ITF parapharyngeal lesions and to determine its advantages, 17 patients with ITF parapharyngeal neoplasms who underwent tumor resection via this approach were enrolled in the study.

Evaluation of variation in the course of the facial nerve, nerve adhesion to tumors, and postoperative facial palsy in acoustic neuroma.

Objective To investigate the variation in the course of the facial nerve (FN) in patients undergoing acoustic neuroma (AN) surgery, its adhesion to tumors, and the relationship between such adhesions and postoperative facial palsy. Methods The subjects were 356 patients who underwent AN surgery in whom the course of the FN could be confirmed. Patients were classified into six groups: ventro-central surface of the tumor (VCe), ventro-rostral (VR), ventro-caudal (VCa), rostral (R), caudal (C), and dorsal (D).

Densely calcified atypical choroid plexus papilloma at the cerebellopontine angle in an adult.

Choroid plexus papilloma is a rare benign tumor accounting for 0.5% of all intracranial tumors. The majority of choroid plexus papillomas occur during the first 2 years of life in the ventricular system.

Surgical management of nonvascular lesions around the oculomotor nerve.

Objective: Schwannomas originating from the oculomotor nerve are extremely rare. We report our experience in the management of oculomotor schwannomas and other lesions mimicking them, and discuss operative strategy for these rare tumors emphasizing oculomotor nerve preservation.

Methods: The clinical records of our patients and all those reported in the literature focusing on oculomotor schwannomas were reviewed and analyzed.

Critical assessment of operative approaches for hearing preservation in small acoustic neuroma surgery: retrosigmoid vs middle fossa approach.

Background: For hearing preservation in acoustic neuroma (AN) surgery, the middle fossa (MF) or retrosigmoid (RS) approach can be used. Recent literature advocates the use of the MF approach, especially for small ANs.

Objective: To present our critical analysis of operative results comparing these 2 approaches.

Hearing preservation in surgery for large vestibular schwannomas.

Object: Hearing preservation remains a challenging problem in vestibular schwannoma (VS) surgery. The ability to preserve hearing in patients with large tumors is subject to particular difficulty. In this study, the authors focus on hearing preservation in patients harboring large VSs.

Intracanalicular meningioma mimicking vestibular schwannoma.

Three cases of intracanalicular meningioma mimicking vestibular schwannoma are presented. In each case, a contrast-enhancing mass filling the internal auditory canal was identified on MR images and was originally diagnosed as a vestibular schwannoma. Although it is difficult to differentiate definitively between these lesions preoperatively, imaging findings inconsistent with a diagnosis of vestibular schwannoma can be identified.

Hearing preservation in acoustic neuroma surgery: importance of adhesion between the cochlear nerve and the tumor.

Object: To evaluate the possible prognostic factors for hearing preservation, the authors retrospectively reviewed the results of 30 consecutive acoustic neuroma operations in which hearing preservation was attempted, in a total series of 63 acoustic neuromas.

Methods: Intracanalicular tumors or those that extended less than 3 mm outside the porus acusticus (10 cases) were resected via the middle fossa approach. The retrosigmoid approach was used for tumors exceeding the limits for the middle fossa approach (20 cases).

Topography of the vestibulocochlear nerve.

Objective: The terms superior vestibular nerve and inferior vestibular nerve have been used in the field of neurosurgery to indicate anatomically the two respective vestibular components of the vestibulocochlear nerve. To reappraise the aptness of this terminology, fascicular patterns and the anatomic relationship of the vestibular and cochlear components were examined.

Methods: Twenty vestibulocochlear nerve specimens were obtained from cadavers.