Luis Serra

Adas3D Medical SL

Background Adapting the ablation index (AI) to the left atrial wall thickness (LAWT) derived from computed tomography angiography (CTA) allows for a personalized approach that showed to improve PVI safety and outcomes. Methods Three observers with different degrees of experience performed complete LAWT analysis of CTA for 30 patients and repeated...

Surgical planning is crucial to Stereoelectroencephalography (SEEG), a minimally invasive procedure that requires clinicians to operate with no direct view of the brain. Decisions making involves different clinical specialties and requires analysis of multiple multimodal datasets. We present a DepthMap tool designed to localize, measure, and visual...

Background and objective : We present SYLVIUS, a software platform intended to facilitate and improve the complex workflow required to diagnose and surgically treat drug-resistant epilepsies. In complex epilepsies, additional invasive information from exploration with stereoencephalography (SEEG) with deep electrodes may be needed, for which the in...

Objective Stereoelectroencephalography (SEEG) consists of the implantation of microelectrodes for the electrophysiological characterization of epileptogenic networks. To reduce a possible risk of intracranial bleeding by vessel rupture during the electrode implantation, the stereotactic trajectories must follow avascular corridors. The use of digit...

The Dextroscope is a surgical planning system that takes advantage of some of the key aspects of virtual reality to maximize the potential of multimodal patient data: two-handed input in 3D and stereoscopic volume-rendering visualization of 3D data. 3D patient models are manipulated in 3D by the surgeon in an easy, intuitive, and flexible manner, w...

Objectives: The aim of this study was to analyze whether scar characterization could improve the risk stratification for life-threatening ventricular arrhythmias and sudden cardiac death (SCD). Background: Among patients with a cardiac resynchronization therapy (CRT) indication, appropriate defibrillator (CRT-D) therapy rates are low. Methods:...

This article presents the Core Expansion method to automatically detect border-zone corridors in MRI images of the left ventricle, to serve as guidance to Ventricular Tachycardia (VT) ablation. The method relies on the fact that the different gray level intensities of Delayed Contrast-Enhanced Magnetic Resonance Images (DE-MRI) encode information a...

An important issue in the deployment of braided stents, such as flow diverters, is the change in length, also known as foreshortening, underwent by the device when is released from the catheter into a blood vessel. The position of the distal end is controlled by the interventionist, but knowing a priori the position of the proximal end of the devic...

Introduction: The purpose of the present contribution is to perform a detailed anatomic and virtual reality three-dimensional stereoscopic study in order to test the effectiveness of the extended endoscopic endonasal approaches for selected anterior and posterior circulation aneurysms. Methods: The study was divided in two main steps: (1) simula...

Background: Conducting channels are the target for ventricular tachycardia (VT) ablation. Conducting channels could be identified with contrast enhanced-cardiac magnetic resonance (ce-CMR) as border zone (BZ) corridors. A 3-dimensional (3D) reconstruction of the ce-CMR could allow visualization of the 3D structure of these BZ channels. Methods an...

Background: In the past 2 decades, intraoperative navigation technology has changed preoperative and intraoperative strategies and methodology tremendously. Objective: To report our first experiences with a stereoscopic navigation system based on multimodality-derived, patient-specific 3-dimensional (3-D) information displayed on a stereoscopic...

Accurate craniotomy placement is essential for frameless neuronavigation in minimally invasive neurosurgery. A craniotomy using virtual reality (VR) can be as accurate as neuronavigation. We prospectively enrolled 48 patients that underwent minimally invasive cranial procedures planned using VR, followed by neuronavigation. First, craniotomies were...

Progress in medical imaging and refined methods of surgery planning, such as Virtual Reality (VR), call for an investigation of the acquisition of three-dimensional (3-D) anatomical knowledge as a crucial goal of medical education. This study compared the efficacy to reconstruct a 3-D arrangement of objects that was either presented as a real model...

We developed an augmented reality system that enables intraoperative image guidance by using 3-dimensional (3D) graphics overlaid on a video stream. We call this system DEX-Ray and report on its development and the initial intraoperative experience in 12 cases. DEX-Ray consists of a tracked handheld probe that integrates a lipstick-size video camer...

An apparatus orients a three-dimensional object in a pre-defined orientation. A source direction determination module determines a source direction matrix corresponding with the pre-defined orientation. A perspective direction determination module determines a perspective direction matrix. An orientation matrix determination module determines an or...

We have developed a highly interactive virtual environment that enables collaborative examination of stereoscopic three-dimensional (3-D) medical imaging data for planning, discussing, or teaching neurosurgical approaches and strategies. The system consists of an interactive console with which the user manipulates 3-D data using hand-held and track...

Exemplary systems and methods are provided by which multiple persons in remote physical locations can collaboratively interactively visualize a 3D data set substantially simultaneously. In exemplary embodiments of the present invention, there can be, for example, a main workstation and one or more remote workstations connected via a data network. A...

A data processing system which allows a user to interactively identify a portion of a volume and display the identified portion of the volume in a way that is particularly adapted for the visualization of the identified portion of the volume. One embodiment provides identifying a location of a volume based on input communicated via an input interfa...

A data processing system which allows a user to interactively identify a portion of a volume and display the identified portion of the volume in a way that is particularly adapted for the visualization of the identified portion of the volume. One embodiment provides identifying a location of a volume based on input communicated via an input interfa...

Methods and systems for rendering high quality 4D ultrasound images in real time, without the use of expensive graphics hardware, without resampling, but also without lowering the resolution of acquired image planes, are presented. In exemplary embodiments according to the present invention, 2D ultrasound image acquisitions with known three dimensi...

For stent graft selection in the treatment of abdominal aortic aneurysms (AAA) anatomic considerations are important. They determine GO/NO-GO of the treatment and help customize the stent. Current systems for AAA stent insertion planning based on pre-operative CT and MR of the patient do not provide an intuitive interface to view the resulting meas...

The ability to manually specify contours in a volumetric data is often required in situations when automatic algorithms are unable to accurately extract the desire volume. Conventionally, the contours are drawn over a slice, working on plane-by-plane basis usually constrained to orthogonal planes. In defining the contour on a 2D image, the user fac...

One embodiment of the present invention includes a system comprising an input interface having at least 3 degrees of spatial freedom for input control; and a diffusion tensor imaging (DTI) module operable with the input interface having at least 3 degrees of spatial freedom. In one embodiment, the DTI module is operable to compute fiber bundles. Th...

A system and method for the imaging management of a 3D space where various substantially real-time scan images have been acquired is presented. In exemplary embodiments according to the present invention, a user can visualize images of a portion of a body or object obtained from a substantially real-time scanner not just as 2D images, but as positi...

A virtual control system for substantially real-time imaging machines, such as, for example, ultrasound, is presented. In exemplary embodiments of the present invention, a virtual control system comprises a physical interface communicably connected to a scanner/imager, such as, for example, an ultrasound machine. The scanner/imager has, or is commu...

A system to visualize and manage the space covered by ultrasound acquisition is presented. This system, SonoDEX, uses a conventional ID transducer array ultrasound probe to create and visualize virtual 3D images in real-time, which can be frozen and reconstructed into volumetric images and then co-registered and fused with pre-segmented volumetric...

We present dividing voxels, a new algorithm to extract iso-surfaces with consistent topology. Unlike marching cubes, we assume the scalar value of a voxel is a physical property of a small volume (not a point) in 3D space. By studying voxel-neighbouring information, our algorithm determines how the iso-surface should be constructed, and avoids the...

Various methods and a system for the display of a luminal organ are presented. In exemplary embodiments according to the present invention numerous two dimensional images of a body portion containing a luminal organ are obtained from scan process. This data is converted to a volume and rendered to a user in various visualizations according to defin...

A system and method for displaying 3D data are presented. The method involves subdividing a 3D display region into two or more display subregions, and assigning a set of display rules to each display subregion. Visible portions of a 3D data set in each display subregion are displayed according to the rules assigned to that display subregion. In an...

A system and method for controlling the scaling of a 3D computer model in a 3D display system include activating a zoom mode, selecting a model zoom point and setting a zoom scale factor are presented. In exemplary embodiments according to the present invention, a system, in response to the selected model zoom point and the set scale factor, can im...

A system and method of presentation of 3D data sets in a 3D display is presented. In exemplary embodiments according to the present invention the method involves displaying data in an overview mode wherein localization markers can be set and manipulated, and in a local mode wherein data surrounding a localization marker can be rendered using differ...

This paper describes an interaction system called the DextroBeam designed for manipulating objects in 3D space while looking at a 3D stereoscopic display located in front of the user. Three-dimensional interaction is two-handed and is achieved by means of a stylus with a single button or switch. We have been planning several neurosurgical cases wit...

A system is presented permitting a user to interact a three-dimensional model. The system displays an image of the model in a workspace. A processor of the system defines (i) a virtual plane intersecting with the displayed model and (ii) a correspondence between the virtual plane and a surface. The user positions a tool on the surface to select a p...

A computer system for permitting user interaction with a three-dimensional computer model defines an initial correspondence between the computer model and a real world workspace. An editing volume of the workspace is also defined, and a stereoscopic image of the section of the computer model within the editing volume is displayed. Using a first inp...

An abstract is not available.

A method of rendering a graphics image in which rendering is only carried out in a region to be changed is disclosed. In a preferred form the image includes a plurality of objects and the method comprises the steps of: determining if each object has changed so that the object is required to be displayed differently in a subsequent frame; determinin...

This surgical planning and training system integrates an electronic atlas of brain structure with a virtual stereotactic frame and patient data, for intuitive, reach-in manipulation. The objective is plans prepared faster; better, more accurate choice of target points; improved avoidance of sensitive structures; fewer sub-optimal frame attachments;...

Medical images of such branching structures as blood vessels are clear to the human visual system, but easily confuse computer vision programs. We present an intuitive, hand-eye coordinated, reach-in interface that allows the user to sketch central curves for arteries, nerves, etc., detectable in volume data and in 3D space, and have this position/...

On many scales, volume data sets often lack the resolution to allow automatic network segmentation, from blood vessels to molten rock channels; even where humans can see the net clearly. We introduce a precise and dextrous environment for users to transform perception to data, using a stereoscopic view for easy identification of vessels. Our tools...

OBJECTIVE: To report our experience with preoperative neurosurgical planning in our stereoscopic virtual reality environment for 21 patients with intra- and extra-axial brain tumors and vascular malformations. METHODS: A neurosurgical planning system called VIVIAN (V irtual I ntracranial Vi sualization a nd N avigation) was developed for the Dextro...

OBJECTIVE To report our experience with preoperative neurosurgical planning in our stereoscopic virtual reality environment for 21 patients with intra- and extra-axial brain tumors and vascular malformations. METHODS A neurosurgical planning system called VIVIAN (V irtual I ntracranial Vi sualization a nd N avigation) was developed for the Dextros...

Based on the KRDL Virtual Workbench, we present a neurosurgical planning system called VIVIAN (Virtual Intracranial Visualization And Navigation). This VR environment allows for fast and intuitive interaction with three-dimensional multimodal (MRI, MRA, MRV, CT) patient specific data-sets. The user reaches behind a mirror into a 3D workspace where...

We have developed a 3D/2D paradigm of interaction that combines manipulation of precise 3D volumetric data with unambiguous widget interaction. Precise 3D interaction is ensured by a combination of resting the lower arms on an armrest and pivoting the hands around the wrist. Unambiguous 2D interaction is achieved by providing passive haptic feedbac...

We present a multimodal volume-based pre-operative surgical planning system developed around the KRDL Virtual Workbench, a mirror-based Virtual Reality system for precise work with 3D data. The planning system is being developed in collaboration with the Singapore General Hospital (SGH), and is undergoing clinical evaluation at SGH and Tan Tock Sen...

We present a virtual reality application to neurosurgical pre-operative planning which is undergoing clinical evaluation at the Singapore General Hospital. The application, based on the ISS Virtual Workbench, lets the neurosurgeon study the brain pathology, blood vessels, skull and the surrounding tissue using real-time volumetric rendering of the...

We present a suite of neurosurgery supporting tools developed around (i) the Virtual Workbench, a productive environment for the control of 3-D data, in which delicate work can be performed for hours on end without strain, and (ii) the Electronic Brain Atlas, integrating the major print brain atlases in day-to-day clinical use. We describe in detai...

Virtual Reality (VR) applications involve the use of manipulators or 'virtual tools' such as pointers, grippers and containers. Manipulation of such tools is a key feature of VR applications. Less attention has been directed towards designing the ways in which users select particular options or information, as they interact in the virtual world, by...

We integrate an electronic atlas of brain structure with a virtual stereotactic frame in a system for intuitive, reach-in manipulation. Clinical study now under way will test our expectation that plans can be prepared faster, with better and more accurate choice of target points, improved avoidance of sensitive structures, fewer abortive frame atta...

A system for visualizing and manipulating medical images is detailed, with emphasis on interaction techniques.

We have developed a 3D reach-in tool to manually reconstruct 3D cortical surface patches from 2D brain atlas images. The first application of our cortex editor is building 3D functional maps, specifically Brodmann's areas. This tool may also be useful in clinical practice to adjust incorrectly mapped atlas regions due to the deforming effect of les...

Any technology for virtual reality limits what can be presented to the user. Games are designed within such limits, but medicine has categorical requirements, more easily met in “reach-in” than in “immersive” VR. We discuss the effects of the needs of medicine on interface and graphics technology, and the achievement of precise, dextrous control fo...

This surgical planning and training system integrates an electronic atlas of brain structure with a virtual stereotactic frame and patient data, for intuitive, reach-in manipulation. The objective is plans prepared faster; better, more accurate choice of target points; improved avoidance of sensitive structures; fewer sub-optimal frame attachments;...

Networked virtual worlds allow multiple virtual worlds connected on a network to share information with one another. Developing such virtual worlds is, however, fraught with many difficulties. Handling both the networking and user interface needs of virtual worlds in an efficient manner poses interesting trade-off-options. In this paper, we discuss...

In a majority of networked virtual worlds, object sharing is limited to object geometries only. The BrickNet toolkit extends the sharing of objects to include dynamic object behaviors. This is achieved by combining a structured organizational paradigm for virtual worlds with an interpreted language. Sharing in virtual worlds is handled by transferr...

To estimate local contraction from tagged MRI heartbeat images, and deduce the presence of non-contributing muscle (usually ischaemic), it is necessary to map the heart contours accurately in each slice at each imaged time. Neither an algorithm nor a human has been found able to do this on the evidence contained in a single slice; machine estimates...

Network-based virtual worlds allow multiple virtual worlds connected on a network to share information with one another. The development effort required to produce a network-based virtual world is quite large. The BrickNet toolkit simplifies this de­velopment by providing the standard facilities required by a wide range of network- based virtual wo...

Developing virtual worlds using toolkits and conventional programming-based approaches is a tedious, time-consuming, and often frustrating task. Too much learning of the toolkits and the basic development technology is necessary before the development can start. Even after that, it takes a long time to develop, test, and modify virtual worlds. At I...

We have created three types of user-eontmlled management tool for use in virtual reality environments: the 3DMenu, the M-Cube, and the SuperCube. 3DMenus are equivalent to the menu systemsfound in two-dimensional interactive environments,but have the necessaryspatial preseneefer the immersive 3D world of a VR application. M-Cubes are directly equiv...

Recent Virtual Reality technical advances have suggested that by encoding subsets of the information using multimedia techniques and placing the resultant visualizations into a perceptual three-dimensional space increases the amount of information that people can meaningfully manage. In order for this approach to be successful, three basic problems...

When people first experience virtual reality they are bound to come away with some misconceptions as to the potential and usefulness of the technology. There is a need for a novice environment in which first-time users can become acquainted with the basic technology and its potential by means of a demonstrative application. A novice environment cal...

We present a model for organizing multimedia information especially suitable for applications with three-dimensional content. The model relies on the hierarchical nature of 3D objects, which are utilized as centralizing structure to give coherence to the organization and access of all other medium types. Techniques have been developed to facilitate...

BRAD3D, a low-cost hardware platform for the development of a realtime 3D graphics software is presented. The BRAD3D configuration is derived from a generalization of 3D image synthesis. Three basic processes have been identified: the geometric process, dealing with the measurements of the scene; the topologic process, extracting visible informatio...

This paper describes KICK-3D, a frame-based interactive 3D graphics environment. KICK-3D is aimed at educational and training applications in which users are given the freedom to explore and experiment with 3D structures and even play with their graphics presentation. The frame formalism is used to model the inter-relations (part-of and kinematic w...

An attempt is being made to produce low-cost real-time displays by utilizing the much improved performance of the latest range of 16 and 32-bit microprocessors. The Video Display Processor (VDP) section of these displays must operate at speeds which necessitate the use of special purpose TTL circuitry. If conventional pixel mapped frame buffers are...