The Role of 3D Tractography in Skull Base Surgery: Technological Advances, Feasibility, and Early Clinical Assessment with Anterior Skull Base Meningiomas.

 The aim of this study is to determine feasibility of incorporating three-dimensional (3D) tractography into routine skull base surgery planning and analyze our early clinical experience in a subset of anterior cranial base meningiomas (ACM).  Ninety-nine skull base endonasal and transcranial procedures were planned in 94 patients and retrospectively reviewed with a further analysis of the ACM subset.  (1) Automated generation of 3D tractography; (2) co-registration 3D tractography with computed tomography (CT), CT angiography (CTA), and magnetic resonance imaging (MRI); and (3) demonstration of real-time manipulation of 3D tractography intraoperatively.

Microsurgical anatomy of the cranial nerve-centric triangles of the posterior cranial base: cadaveric and radiological anatomical study.

Tumors in the posterior fossa can be situated either dorsal and lateral, ventral and medial, or occupying both regions in relation to the cranial nerves, with the latter position being especially challenging. In an effort to organize neurovascular complexes contained within, anatomically based triangles have been proposed to serve as guiding landmarks for locating critical neurovascular structures. The objectives of this study were to: (1) provide a review of historical anatomically based vascular-centric triangles of the posterior fossa based on respective neurovascular complexes; (2) introduce a more organized alternative system of triangles with the conceptualization of a projection system from superficial to deep; and (3) propose and describe two new triangles of the posterior fossa: Petrous-Acousticofacial and Acousticofacial-Trigeminal.

Combined Decompressive Hemicraniectomy and Port-Based Minimally Invasive Parafascicular Surgery for the Treatment of Subcortical Intracerebral Hemorrhage: Case Series, Technical Note, and Review of Literature.

Background: Intracerebral hemorrhage (ICH) is a neurosurgical emergency. Combined decompressive hemicraniectomy (DHC) and minimally invasive parafascicular surgery (MIPS) may provide a practical method of managing subcortical ICH.

Objective: 1) To present a case series of combined DHC-MIPS for the treatment of subcortical-based ICH; 2) to describe technical nuances of DHC-MIPS; and 3) to provide a literature overview of MIPS for ICH.

The Evolution of Cerebral Language Localization: Historical Analysis and Current Trends.

Language localization has been an evolving concept over the past 150 years, with the emergence of several important yet conflicting ideologies. The classical theory, starting from the phrenologic work of Gall to the identification of specific regions of language function by Broca, Wernicke, and others, proposed that discrete subcomponents of language were organized into separate anatomic structural regions. The holism theory was postulated in an attempt to disclose that language function was instead attributed to a larger region of the cortex, in which cerebral regions may have the capability of assuming the function of damaged areas.

Minimally invasive trans-sulcal parafascicular surgical resection of cerebral tumors: translating anatomy to early clinical experience.

The minimally invasive port-based trans-sulcal parafascicular surgical corridor (TPSC) has incrementally evolved to provide a safe, feasible, and effective alternative to access subcortical and intraventricular pathologies. A detailed anatomical foundation is important in mitigating cortical and white matter tract injury with this corridor. Thus, the aims of this study are (1) to provide a detailed anatomical construct and overview of TPSCs and (2) to translate an anatomical framework to early clinical experience.

White Matter Governed Superior Frontal Sulcus Surgical Paradigm: A Radioanatomic Microsurgical Study-Part II.

Background: Kocher's point (KP) and its variations have provided standard access to the frontal horn (FH) for over a century. Anatomic understanding of white matter tracts (WMTs) has evolved, now positioning us to better inform the optimal FH trajectory.

Objective: To (1) undertake a literature review analyzing entry points (EPs) to the FH; (2) introduce a purpose-built WMT-founded superior frontal sulcus parafascicular (SFSP)-EP also referred to as the Kassam-Monroy entry point (KM-EP); and (3) compare KM-EP with KP and variants with respect to WMTs.

Minimally Invasive Parafascicular Surgical Approach for the Management of a Pediatric Third Ventricular Ependymoma: Case Report and Review of Literature.

Background: Minimally invasive parafascicular surgery (MIPS) has evolved into a safe alternative to access deep-seated subcortical and intraventricular pathologies. We present a case of a port-mediated resection of a pediatric third ventricular tumor.

Case Description: The patient is a 7-year-old boy who presented with worsening headache, nausea, vomiting, dizziness, unsteady gait, photophobia, and blind spots with positional changes.

White Matter-Governed Superior Frontal Sulcus Surgical Paradigm: A Radioanatomic Microsurgical Study-Part I.

Background: Frontal subcortical and intraventricular pathologies are traditionally accessed via transcortical or interhemispheric-transcallosal corridors.

Objective: To describe the microsurgical subcortical anatomy of the superior frontal sulcus (SFS) corridor.

Methods: Cadaveric dissections were undertaken and correlated with magnetic resonance imaging/diffusion-tensor imaging-Tractography.

Initial Experience with Exoscopic-Based Intraoperative Indocyanine Green Fluorescence Video Angiography in Cerebrovascular Surgery: A Preliminary Case Series Showing Feasibility, Safety, and Next-Generation Handheld Form-Factor.

Background: Native vessel patency and residual lesion are primary sources of morbidity in cerebrovascular surgery (CVS) that require real-time visualization to inform surgical judgment, as is available in endovascular procedures. Micro Doppler and microscopy-based indocyanine green (ICG) fluorescence are promising evolutions compared with intraoperative angiography (IA), and digital subtraction angiography (DSA) remains the gold standard. Exoscopic visualization in CVS is emerging; however, the feasibility of exoscopic-based ICG (ICG-E) for CVS has not yet been reported.

Does the method of visualization impact the performance of a new surgical task in novice subjects?

Introduction: Evolution of optical technology from two-dimensional to three-dimensional (3D) systems has come with an associated loss of stereoscopy and 3D depth perception. This report compares performance of surgical tasks in unbiased subjects using these systems.

Methods: Untrained subjects were randomized into two groups, robotically operated video optical telescopic-microscope (ROVOT) or surgical microscope (microscope).

An Anatomically-Based Endoscopic Endonasal Model to Navigate the Anterior Ventral Skull Base.

Background: Endoscopic endonasal approaches to access the sellar and parasellar regions are challenging in the face of anatomical variations or pathologic conditions. We propose an anatomically-based model including the orbitosellar line (OSL), critical oblique foramen line (COFL), and paramedial anterior line (PAL) facilitating safe, superficial-to-deep dissection triangulating upon the medial opticocarotid recess.

Methods: Five cadaveric heads were dissected to systematically expose the OSL, COFL, and PAL, illustrated with image guidance.

Awake Surgical Management of Third Ventricular Tumors: A Preliminary Safety, Feasibility, and Clinical Applications Study.

Background: Endoscopic and microneurosurgical approaches to third ventricular lesions are commonly performed under general anesthesia.

Objective: To report our initial experience with awake transsulcal parafascicular corridor surgery (TPCS) of the third ventricle and its safety, feasibility, and limitations.

Methods: A total of 12 cases are reviewed: 6 colloid cysts, 2 central neurocytomas, 1 papillary craniopharyngioma, 1 basal ganglia glioblastoma, 1 thalamic glioblastoma, and 1 ependymal cyst.

Microsurgical Anatomy of the Vertical Rami of the Superior Longitudinal Fasciculus: An Intraparietal Sulcus Dissection Study.

Background: A number of vertical prolongations of the superior longitudinal fasciculus, which we refer to as the vertical rami (Vr), arise at the level of the supramarginal gyrus, directed vertically toward the parietal lobe.

Objective: To provide the first published complete description of the white matter tracts (WMT) of the Vr, their relationship to the intraparietal and parieto-occipital sulci (IPS-POS complex), and their importance in neurosurgical approaches to the parietal lobe.

Methods: Subcortical dissections of the Vr and WMT of the IPS were performed.

Reanalyzing the "far medial" (transcondylar-transtubercular) approach based on three anatomical vectors: the ventral posterolateral corridor.

Endoscopic endonasal access to the jugular foramen and occipital condyle - the transcondylar-transtubercular approach - is anatomically complex and requires detailed knowledge of the relative position of critical neurovascular structures, in order to avoid inadvertent injury and resultant complications. However, access to this region can be confusing as the orientation and relationships of osseous, vascular, and neural structures are very much different from traditional dorsal approaches. This review aims at providing an organizational construct for a more understandable framework in accessing the transcondylar-transtubercular window.

Endoscopic Endonasal Reconstructive Methods to the Anterior Skull Base.

The success of expanded endoscopic endonasal approaches (EEAs) to the anterior skull base, sellar, and parasellar regions has been greatly aided by the advancement in reconstructive techniques. In particular, the pedicled vascularized flaps have been developed and effectively cover skull base defects of varying sizes with a significant reduction in postoperative CSF leaks. There are two aims to this review: (1) We will provide our current, simplified reconstruction algorithm.

The Surgical White Matter Chassis: A Practical 3-Dimensional Atlas for Planning Subcortical Surgical Trajectories.

Background: The imperative role of white matter preservation in improving surgical functional outcomes is now recognized. Understanding the fundamental white matter framework is essential for translating the anatomic and functional literature into practical strategies for surgical planning and neuronavigation.

Objective: To present a 3-dimensional (3-D) atlas of the structural and functional scaffolding of human white matter-ie, a "Surgical White Matter Chassis (SWMC)"-that can be used as an organizational tool in designing precise and individualized trajectory-based neurosurgical corridors.

A morphometric survey of the parasellar region in more than 2700 skulls: emphasis on the middle clinoid process variants and implications in endoscopic and microsurgical approaches.

OBJECTIVE The middle clinoid process (MCP) is a bony projection that extends from the sphenoid bone near the lateral margin of the sella turcica. The varied prevalence and morphological features of the MCP in populations stratified by age, race, and sex are unknown; however, the knowledge of its anatomy and preoperative recognition on CT scans can aid greatly in complication avoidance and management. The aim of this study was to further illustrate the surgical anatomy of the parasellar region and to quantify the incidence of MCP and caroticoclinoid rings (CCRs) in dried preserved human anatomical specimens.

The Operating Room of the Future Versus the Future of the Operating Room.

Technological advancement in the operating room is evolving into a dynamic system mirroring that of the aeronautics industry. Through data visualization, information is continuously being captured, collected, and stored on a scalable informatics platform for rapid, intuitive, iterative learning. The authors believe this philosophy (paradigm) will feed into an intelligent informatics domain fully accessible to all and geared toward precision, cell-based therapy in which tissue can be targeted and interrogated in situ.

Initial experience with a robotically operated video optical telescopic-microscope in cranial neurosurgery: feasibility, safety, and clinical applications.

OBJECTIVE The move toward better, more effective optical visualization in the field of neurosurgery has been a focus of technological innovation. In this study, the authors' objectives are to describe the feasibility and safety of a new robotic optical platform, namely, the robotically operated video optical telescopic-microscope (ROVOT-m), in cranial microsurgical applications. METHODS A prospective database comprising patients who underwent a cranial procedure between April 2015 and September 2016 was queried, and the first 200 patients who met the inclusion criteria were selected as the cohort for a retrospective chart review.

Enzymatic activity of free-prostate-specific antigen (f-PSA) is not required for some of its physiological activities.

Background: Prostate specific antigen (PSA) is a well known biomarker for early diagnosis and management of prostate cancer. Furthermore, PSA has been documented to have anti-angiogenic and anti-tumorigenic activities in both in vitro and in vivo studies. However, little is known about the molecular mechanism(s) involved in regulation of these processes, in particular the role of the serine-protease enzymatic activity of PSA.