Challenges with segmenting intraoperative ultrasound for brain tumours.

Objective - Addressing the challenges that come with identifying and delineating brain tumours in intraoperative ultrasound. Our goal is to both qualitatively and quantitatively assess the interobserver variation, amongst experienced neuro-oncological intraoperative ultrasound users (neurosurgeons and neuroradiologists), in detecting and segmenting brain tumours on ultrasound. We then propose that, due to the inherent challenges of this task, annotation by localisation of the entire tumour mass with a bounding box could serve as an ancillary solution to segmentation for clinical training, encompassing margin uncertainty and the curation of large datasets.

The classical supraorbital minicraniotomy to approach the areas of origin of anterior skull base meningiomas: Anatomical nuances influencing accessibility, operability, and frontal lobe retraction.

Background: The classical supraorbital minicraniotomy (cSOM) constitutes a minimally invasive alternative for the resection of anterior skull base meningiomas (ASBM). Surgical success depends strongly on optimal patient selection and surgery planning, for which a careful assessment of tumor characteristics, approach trajectory, and bony anterior skull base anatomy is required. Still, morphometrical studies searching for relevant anatomical factors with surgical relevance when intending a cSOM for ASBM resection are lacking.

Using Mixed Reality Simulation to Improve Junior Medical Trainees' Preparedness to Manage High-Acuity Trauma.

High-acuity trauma necessitates experienced and rapid intervention to prevent patient harm. However, upskilling junior trainees through hands-on management of real trauma cases is rarely feasible without compromising patient safety. This quality education report sought to investigate whether a simulation course operated via mixed reality (MR) headset devices (Microsoft HoloLens) could enhance the clinical knowledge recall and preparedness to practice of junior trainees with no prior experience managing trauma.

Effect of Mixed Reality on Delivery of Emergency Medical Care in a Simulated Environment: A Pilot Randomized Crossover Trial.

Importance: Mixed-reality (MR) technology has the potential to enhance care delivery, but there remains a paucity of evidence for its efficacy and feasibility.

Objective: To assess the efficacy and feasibility of MR technology to enhance emergency care delivery in a simulated environment.

Design, Setting, And Participants: This pilot randomized crossover trial was conducted from September to November 2021 at a single center in a high-fidelity simulated environment with participants block randomized to standard care (SC) or MR-supported care (MR-SC) groups.

The Endoscopic-Assisted Supraorbital Approach for Resection of Anterior Skull Base Meningiomas: A Large Single-Center Retrospective Surgical Study.

 The endoscopic-assisted supraorbital approach (eSOA) constitutes a minimally invasive strategy for removing anterior skull base meningiomas (ASBM). We present the largest retrospective single-institution and long-term follow-up study of eSOA for ASBM resection, providing further insight regarding indication, surgical considerations, complications, and outcome.  We evaluated data of 176 patients operated on ASBM via the eSOA over 22 years.

Variants of the Anterior Subtemporal Approach to the Gasserian Ganglion and Related Structures: An Anatomical Study With Relevant Implications for Keyhole Surgery.

Background: The advantages and limitations of different craniotomy positions and approach trajectories to the gasserian ganglion (GG) and related structures using an anterior subtemporal approach have not been studied systematically. Knowledge of these features is of importance when planning keyhole anterior subtemporal (kAST) approaches to the GG to optimize access and minimize risks.

Methods: Eight formalin-fixed heads were used bilaterally to assess temporal lobe retraction (TLR), trigeminal exposure, and relevant anatomical aspects of extra- and transdural classic anterior subtemporal (CLAST) approaches compared with slightly dorsally and ventrally allocated corridors.

Endoscopic-assisted paramedian supracerebellar infratentorial approach to the posterior portion of the third ventricle: anatomical study and surgical cases.

Background: To date, morphometrical data providing a systematic quantification of accessibility and operability parameters to the boundaries of the posterior portion of the third ventricle (PTV) when applying an endoscopic-assisted paramedian supracerebellar infratentorial approach (EPSIA) are lacking. We performed an anatomical study and complemented our findings with surgical cases.

Methods: Eight EPSIAs towards the PTV were performed in cadaveric specimens.

Two-stage endoscopic assisted approach for large pineal region and falcotentorial meningioma: first stage paramedian supracerebellar infratentorial approach, second stage interhemispheric occipital transtentorial approach: surgical cases and anatomical study.

Resection of complex falcotentorial meningiomas, growing along the pineal region (PR), and posterior incisural space (PIS) represents a neurosurgical challenge. Here, we present our strategy for effective resection of large falcotentorial meningiomas applying a paramedian supracerebellar infratentorial and interhemispheric occipital transtentorial approach in staged surgeries. We further systematically compared the effectiveness of midline (MSIA) and paramedian (PSIA) supracerebellar infratentorial, as well as interhemispheric occipital transtentorial approaches (IOTA) to operate along the PR and PIS in 8 cadaveric specimens.

Effect of in vitro aging by water immersion and thermocycling on the mechanical properties of PETG aligner material.

Purpose: The mechanical properties of orthodontic aligners made from thermoplastic polymers decrease over time in the intraoral milieu. However, there is a lack of information on this topic in the literature. Thus, the elastic properties of polyethylene terephthalate glycol (PETG) aligner films were investigated in vitro under extreme temperature changes simulated by thermocycling, environmental temperature and water absorption.

The approach angle to the interoptic triangle limits surgical workspace when targeting the contralateral internal carotid artery.

Background: The interoptic triangle (IOT) offers a key access to the contralateral carotid artery's ophthalmic segment (oICA) and its perforating branches (PB), the ophthalmic artery (OA), and the superior hypophyseal artery (SHA). It has been previously reported that the assessment of IOT's size is relevant when attempting approaches to the contralateral oICA. However, previous studies have overseen that, since the oICA is a paramedian structure and a lateralized contralateral approach trajectory is then required, the real access to the oICA is further limited by the approach angle adopted by the surgeon with respect to the IOT's plane.

Comprehensive Anatomic Assessment of Ipsilateral Pterional Versus Contralateral Subfrontal Approaches to the Internal Carotid Ophthalmic Segment: A Cadaveric Study and Three-Dimensional Simulation.

Objective: Medially pointing aneurysms of the ophthalmic segment of the internal carotid artery (oICA) represent a neurosurgical challenge. Conventional ipsilateral approaches require internal carotid artery and optic nerve (ON) mobilization as well as anterior clinoidectomy (AC), all associated with increased surgical risk. Contralateral approaches could provide a better exposure of the superomedial aspect of the oICA, ophthalmic artery, and superior hypophyseal artery, sparing AC and internal carotid artery or ON mobilization.

A literature review concerning contralateral approaches to paraclinoid internal carotid artery aneurysms.

Ipsilateral approaches remain the standard technique for clipping paraclinoid aneurysms. Surgeons must however be prepared to deal with bony and neural structures restricting accessibility. The application of a contralateral approach has been proposed claiming that some structures in the region can be better exposed from this side.

Case series of posterior instrumentation for repair of burst lumbar vertebral body fractures with entrapped neural elements.

Background: Burst fractures of the lumbar vertebrae and laminar fractures associated with dural tears and entrapment of neural elements have been reported in the past as a relatively rare occurrence. To the best of our knowledge, there is no consensus on the approach to repairing these types of fractures. The objective of this study is to describe a method of repair for traumatic burst fractures of the lumbar spine and vertical laminar fractures associated with entrapped neural elements.

Rates of Upper Facet Joint Violation in Minimally Invasive Percutaneous and Open Instrumentation: A Comparative Cohort Study of Different Insertion Techniques.

Background:  Minimally invasive pedicle screw placement may have a higher incidence of violation of the superior cephalad unfused facet joint.

Study Aims:  We investigated the incidence and risk factors of upper facet joint violation in percutaneous robot-assisted instrumentation versus percutaneous fluoroscopy-guided and open transpedicular instrumentation.

Methods:  A retrospective study including all consecutive patients who underwent lumbar instrumentation, fusion, and decompression for spondylolisthetic stenosis and degenerative disk disease was conducted between January 2012 and January 2016.

Autostereoscopic Three-Dimensional Neuronavigation to the Sella: Technical Note.

Background: A drawback of conventional neuronavigation is the necessity of focusing on two-dimensional images in 3 planes at the same time to determine one's position in the operating field. A solution would be to merge the images into a single three-dimensional (3D) image that mirrors the actual anatomy. The introduction of holographic glassless 3D monitors paved the way to 3D navigation.

A novel minimally invasive, dorsolateral, tubular partial odontoidectomy and autologous bone augmentation to treat dens pseudarthrosis: cadaveric, 3D virtual simulation study and technical report.

OBJECTIVE The goal of this study was to demonstrate the clinical and technical nuances of a minimally invasive, dorsolateral, tubular approach for partial odontoidectomy, autologous bone augmentation, and temporary C1-2 fixation to treat dens pseudarthrosis. METHODS A cadaveric feasibility study, a 3D virtual reality reconstruction study, and the subsequent application of this approach in 2 clinical cases are reported. Eight procedures were completed in 4 human cadavers.

C-OnSite ® for intraoperative 3D control of pedicular screw positions.

Background: Two-dimensional image guidance and navigation can help to reduce the number of misplaced pedicle screws, but do not completely prevent misplacement. This experimental, retrospective, non-inferiority study was designed to evaluate and compare the efficacy of a novel 3D imaging technique versus conventional postoperative CT-scan, for intra-operative determination of pedicle screw position accuracy.

Methods: The capacity of C-OnSite® to intraoperatively assess screw placement was evaluated in 28 clinical cases and 23 deliberately misplaced screws in a cadaver model, and compared to placement accuracy determined by standard CT.