Targeting accuracy of neuronavigation: a comparative evaluation of an innovative wearable AR platform vs. traditional EM navigation.

Wearable augmented reality in neurosurgery offers significant advantages by enabling the visualization of navigation information directly on the patient, seamlessly integrating virtual data with the real surgical field. This ergonomic approach can facilitate a more intuitive understanding of spatial relationships and guidance cues, potentially reducing cognitive load and enhancing the accuracy of surgical gestures by aligning critical information with the actual anatomy in real-time. This study evaluates the benefits of a novel AR platform, VOSTARS, by comparing its targeting accuracy to that of the gold-standard electromagnetic (EM) navigation system, Medtronic StealthStation S7.

Augmented reality for rhinoplasty: 3D scanning and projected AR for intraoperative planning validation.

Rhinoplasty is one of the major surgical procedures most popular and it is generally performed modelling the internal bones and cartilage using a closed approach to reduce the damage of soft tissue, whose final shape is determined by means of their new settlement over the internal remodelled rigid structures. An optimal planning, achievable thanks to advanced acquisition of 3D images and thanks to the virtual simulation of the intervention via specific software. Anyway, the final result depends also on factors that cannot be totally predicted regarding the settlement of soft tissues on the rigid structures, and a final objective check would be useful to eventually perform some adjustments before to conclude the intervention.

Computational surgery in the management of patients with abdominal aortic aneurysms: Opportunities, challenges, and future directions.

Computational surgery (CS) is an interdisciplinary field that uses mathematical models and algorithms to focus specifically on operative planning, simulation, and outcomes analysis to improve surgical care provision. As the digital revolution transforms the surgical work environment through broader adoption of artificial intelligence and machine learning, close collaboration between surgeons and computational scientists is not only unavoidable, but will become essential. In this review, the authors summarize the main advances, as well as ongoing challenges and prospects, that surround the implementation of CS techniques in vascular surgery, with a particular focus on the care of patients affected by abdominal aortic aneurysms (AAAs).

Visualization modality for augmented reality guidance of in-depth tumour enucleation procedures.

Recent research studies reported that the employment of wearable augmented reality (AR) systems such as head-mounted displays for the in situ visualisation of ultrasound (US) images can improve the outcomes of US-guided biopsies through reduced procedure completion times and improved accuracy. Here, the authors continue in the direction of recent developments and present the first AR system for guiding an in-depth tumour enucleation procedure under US guidance. The system features an innovative visualisation modality with cutting trajectories that 'sink' into the tissue according to the depth reached by the electric scalpel, tracked in real-time, and a virtual-to-virtual alignment between the scalpel's tip and the trajectory.

Registration Sanity Check for AR-guided Surgical Interventions: Experience From Head and Face Surgery.

Achieving and maintaining proper image registration accuracy is an open challenge of image-guided surgery. This work explores and assesses the efficacy of a registration sanity check method for augmented reality-guided navigation (AR-RSC), based on the visual inspection of virtual 3D models of landmarks. We analyze the AR-RSC sensitivity and specificity by recruiting 36 subjects to assess the registration accuracy of a set of 114 AR images generated from camera images acquired during an AR-guided orthognathic intervention.

COVID-19 and Fatty Liver Disorders.

In late 2019, the world was shaken by the COVID-19 pandemic. Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection became one of the main causes of illness and hospitalization worldwide, especially in subjects with metabolic comorbidities such as obesity, diabetes, or liver disease. This scenario crosses with the metabolic liver disorders' "pandemic", caused by the exponential spreading of non-alcoholic fatty liver disease, which is now the most prevalent cause of chronic liver disease (CLD).

Head-Mounted Projector for Manual Precision Tasks: Performance Assessment.

The growing interest in augmented reality applications has led to an in-depth look at the performance of head-mounted displays and their testing in numerous domains. Other devices for augmenting the real world with virtual information are presented less frequently and usually focus on the description of the device rather than on its performance analysis. This is the case of projected augmented reality, which, compared to head-worn AR displays, offers the advantages of being simultaneously accessible by multiple users whilst preserving user awareness of the environment and feeling of immersion.

Magic Leap 1 versus Microsoft HoloLens 2 for the Visualization of 3D Content Obtained from Radiological Images.

The adoption of extended reality solutions is growing rapidly in the healthcare world. Augmented reality (AR) and virtual reality (VR) interfaces can bring advantages in various medical-health sectors; it is thus not surprising that the medical MR market is among the fastest-growing ones. The present study reports on a comparison between two of the most popular MR head-mounted displays, Magic Leap 1 and Microsoft HoloLens 2, for the visualization of 3D medical imaging data.

Safety and Immunogenicity of Anti-SARS-CoV-2 Booster Dose in Patients with Chronic Liver Disease.

The low response to vaccines is a well-known problem in cirrhosis. We evaluated the safety and immunogenicity of booster doses in patients with chronic liver disease (CLD), comparing the humoral response in cirrhotic vs. non-cirrhotic patients, and the impact of different factors on immune response.

A Rendering Engine for Integral Imaging in Augmented Reality Guided Surgery.

In the field of image-guided surgery, Augmented Reality wearable displays are a widely studied and documented technology for their ability to provide egocentric vision together with the overlap between real and virtual content. In particular, optical see-through (OST) displays have the advantage of maintaining visual perception of the real world. However, OST displays suffer from vergeance-accomodation conflict when virtual content is superimposed on real world.

Single feature constrained manual registration method for Augmented Reality applications in gynecological laparoscopic interventions.

Augmented Reality (AR) can avoid some of the drawbacks of Minimally Invasive Surgery and may provide opportunities for developing innovative tools to assist surgeons. In laparoscopic surgery, the achievement of easy and sufficiently accurate registration is an open challenge. This is particularly true in procedures, such as laparoscopic abdominal Sacro-Colpopexy, where there is a lack of a sufficient number of visible anatomical landmarks to be used as a reference for registration.

Augmented Reality as a Tool to Guide Patient-Specific Templates Placement in Pelvic Resections.

Patient-specific templates (PST) have become a useful tool for guiding osteotomy in complex surgical scenarios such as pelvic resections. The design of the surgical template results in sharper, less jagged resection margins than freehand cuts. However, their correct placement can become difficult in some anatomical regions and cannot be verified during surgery.

Errata to "Parallax Free Registration for Augmented Reality Optical See-Through Displays in the Peripersonal Space" [1] (DOI: 10.1109/TVCG.2020.3021534).

In the original article, there was a mistake in the content of Table 2 page 8 column 1 as published. The values of the mean and standard deviation of the virtual-to-real overlay error in visual angles, which are reported for different checkerboard distances, are to be corrected. Due to a typing error within the data analysis code, we mistakenly considered an erroneous value of the average angular resolution for the eye-replacement camera.

Corrigendum: Optical See-Through Head-Mounted Displays With Short Focal Distance: Conditions for Mitigating Parallax-Related Registration Error.

[This corrects the article DOI: 10.3389/frobt.2020.

Brain Tumor and Augmented Reality: New Technologies for the Future.

In recent years, huge progress has been made in the management of brain tumors, due to the availability of imaging devices, which provide fundamental anatomical and pathological information not only for diagnostic purposes [...

In Situ Visualization for 3D Ultrasound-Guided Interventions with Augmented Reality Headset.

Augmented Reality (AR) headsets have become the most ergonomic and efficient visualization devices to support complex manual tasks performed under direct vision. Their ability to provide hands-free interaction with the augmented scene makes them perfect for manual procedures such as surgery. This study demonstrates the reliability of an AR head-mounted display (HMD), conceived for surgical guidance, in navigating in-depth high-precision manual tasks guided by a 3D ultrasound imaging system.

Augmented Reality-Assisted Craniotomy for Parasagittal and Convexity En Plaque Meningiomas and Custom-Made Cranio-Plasty: A Preliminary Laboratory Report.

Background: This report discusses the utility of a wearable augmented reality platform in neurosurgery for parasagittal and convexity en plaque meningiomas with bone flap removal and custom-made cranioplasty.

Methods: A real patient with en plaque cranial vault meningioma with diffuse and extensive dural involvement, extracranial extension into the calvarium, and homogeneous contrast enhancement on gadolinium-enhanced T1-weighted MRI, was selected for this case study. A patient-specific manikin was designed starting with the segmentation of the patient's preoperative MRI images to simulate a craniotomy procedure.

Can Liquid Lenses Increase Depth of Field in Head Mounted Video See-Through Devices?

Wearable Video See-Through (VST) devices for Augmented Reality (AR) and for obtaining a Magnified View are taking hold in the medical and surgical fields. However, these devices are not yet usable in daily clinical practice, due to focusing problems and a limited depth of field. This study investigates the use of liquid-lens optics to create an autofocus system for wearable VST visors.

Evaluation of a Wearable AR Platform for Guiding Complex Craniotomies in Neurosurgery.

Today, neuronavigation is widely used in daily clinical routine to perform safe and efficient surgery. Augmented reality (AR) interfaces can provide anatomical models and preoperative planning contextually blended with the real surgical scenario, overcoming the limitations of traditional neuronavigators. This study aims to demonstrate the reliability of a new-concept AR headset in navigating complex craniotomies.

Hybrid Simulation and Planning Platform for Cryosurgery with Microsoft HoloLens.

Cryosurgery is a technique of growing popularity involving tissue ablation under controlled freezing. Technological advancement of devices along with surgical technique improvements have turned cryosurgery from an experimental to an established option for treating several diseases. However, cryosurgery is still limited by inaccurate planning based primarily on 2D visualization of the patient's preoperative images.

Head-Mounted Augmented Reality Platform for Markerless Orthopaedic Navigation.

Visual augmented reality (AR) has the potential to improve the accuracy, efficiency and reproducibility of computer-assisted orthopaedic surgery (CAOS). AR Head-mounted displays (HMDs) further allow non-eye-shift target observation and egocentric view. Recently, a markerless tracking and registration (MTR) algorithm was proposed to avoid the artificial markers that are conventionally pinned into the target anatomy for tracking, as their use prolongs surgical workflow, introduces human-induced errors, and necessitates additional surgical invasion in patients.

Optical See-Through Head-Mounted Displays With Short Focal Distance: Conditions for Mitigating Parallax-Related Registration Error.

Optical see-through (OST) augmented reality head-mounted displays are quickly emerging as a key asset in several application fields but their ability to profitably assist high precision activities in the peripersonal space is still sub-optimal due to the calibration procedure required to properly model the user's viewpoint through the see-through display. In this work, we demonstrate the beneficial impact, on the parallax-related AR misregistration, of the use of optical see-through displays whose optical engines collimate the computer-generated image at a depth close to the fixation point of the user in the peripersonal space. To estimate the projection parameters of the OST display for a generic viewpoint position, our strategy relies on a dedicated parameterization of the virtual rendering camera based on a calibration routine that exploits photogrammetry techniques.

The Wearable VOSTARS System for Augmented Reality-Guided Surgery: Preclinical Phantom Evaluation for High-Precision Maxillofacial Tasks.

Background: In the context of guided surgery, augmented reality (AR) represents a groundbreaking improvement. The Video and Optical See-Through Augmented Reality Surgical System (VOSTARS) is a new AR wearable head-mounted display (HMD), recently developed as an advanced navigation tool for maxillofacial and plastic surgery and other non-endoscopic surgeries. In this study, we report results of phantom tests with VOSTARS aimed to evaluate its feasibility and accuracy in performing maxillofacial surgical tasks.

Parallax Free Registration for Augmented Reality Optical See-Through Displays in the Peripersonal Space.

Egocentric augmented reality (AR) interfaces are quickly becoming a key asset for assisting high precision activities in the peripersonal space in several application fields. In these applications, accurate and robust registration of computer-generated information to the real scene is hard to achieve with traditional Optical See-Through (OST) displays given that it relies on the accurate calibration of the combined eye-display projection model. The calibration is required to efficiently estimate the projection parameters of the pinhole model that encapsulate the optical features of the display and whose values vary according to the position of the user's eye.

Selectivity Control in Gold-Catalyzed Hydroarylation of Alkynes with Indoles: Application to Unsymmetrical Bis(indolyl)methanes.

Gold-catalyzed hydroarylation of unactivated alkynes with indoles have previously been reported to proceed with double indole addition to produce symmetrical bis(indolyl)methanes (BIMs). We demonstrate for the first time that the selectivity of the gold-catalyzed reaction can be fully switched to allow for isolation of the vinylindole products instead. Furthermore, this selective reaction can be utilized to synthesize the more difficult to access unsymmetrical BIMs from readily available starting materials.