3D Guidance Research Articles

Application of 3D Guidance Technique in Endovascular Aortic Repair

Application of 3D Guidance Technique in Endovascular Aortic Repair

Three-dimensional Augmented Reality Robot-assisted Partial Nephrectomy in Case of Complex Tumours (PADUA ≥10): A New Intraoperative Tool Overcoming the Ultrasound Guidance

BackgroundDespite technical improvements introduced with robotic surgery, management of complex tumours (PADUA score ≥10) is still a matter of debate within the field of transperitoneal robot-assisted partial nephrectomy (RAPN). ObjectiveTo evaluate the accuracy of our three-dimensional (3D) static and elastic augmented reality (AR) systems based on hyperaccuracy models (HA3D) in identifying tumours and intrarenal structures during transperitoneal RAPN (AR-RAPN), compared with standard ultrasound (US). Design, setting, and participantsA retrospective study was conducted, including 91 patients who underwent RAPN for complex renal tumours, 48 with 3D AR guidance and 43 with 2D US guidance, from July 2017 to May 2019. Surgical procedureIn patients who underwent 3D AR-RAPN, virtual image overlapping guided the surgeon during resection and suture phases. In the 2D US group, interventions were driven by US only. MeasurementsPatient characteristics were tested using the Fisher’s exact test for categorical variables and the Mann-Whitney test for continuous ones. Intraoperative, postoperative, and surgical outcomes were collected. All results for continuous variables were expressed as medians (range), and frequencies and proportions were reported as percentages. Results and limitationsThe use of 3D AR guidance makes it possible to correctly identify the lesion and intraparenchymal structures with a more accurate 3D perception of the location and the nature of the different structures relative to the standard 2D US guidance. This translates to a lower rate of global ischaemia (45.8% in the 3D group vs 69.7% in the US group; p = 0.03), higher rate of enucleation (62.5% vs 37.5% in the 3D and US groups, respectively; p = 0.02), and lower rate of collecting system violation (10.4% vs 45.5%; p = 0.003). Postoperatively, 3D AR guidance use correlates to a low risk of surgery-related complications in 3D AR groups and a lower drop in estimated renal plasma flow at renal scan at 3 mo of follow-up (–12.38 in the 3D group vs –18.14 in the US group; p = 0.01). The main limitations of this study are short follow-up time and small sample size. ConclusionsHA3D models that overlap in vivo anatomy during AR-RAPN for complex tumours can be useful for identifying the lesion and intraparenchymal structures that are difficult to visualise with US only. This translates to a potential improvement in the quality of the resection phase and a reduction in postoperative complications, with better functional recovery. Patient summaryBased on our findings, three-dimensional augmented reality robot-assisted partial nephrectomy seems to help surgeons in the management of complex renal tumours, with potential early postoperative benefits.

Smooth 3D Path Planning by Means of Multiobjective Optimization for Fixed-Wing UAVs

Demand for 3D planning and guidance algorithms is increasing due, in part, to the increase in unmanned vehicle-based applications. Traditionally, two-dimensional (2D) trajectory planning algorithms address the problem by using the approach of maintaining a constant altitude. Addressing the problem of path planning in a three-dimensional (3D) space implies more complex scenarios where maintaining altitude is not a valid approach. The work presented here implements an architecture for the generation of 3D flight paths for fixed-wing unmanned aerial vehicles (UAVs). The aim is to determine the feasible flight path by minimizing the turning effort, starting from a set of control points in 3D space, including the initial and final point. The trajectory generated takes into account the rotation and elevation constraints of the UAV. From the defined control points and the movement constraints of the UAV, a path is generated that combines the union of the control points by means of a set of rectilinear segments and spherical curves. However, this design methodology means that the problem does not have a single solution; in other words, there are infinite solutions for the generation of the final path. For this reason, a multiobjective optimization problem (MOP) is proposed with the aim of independently maximizing each of the turning radii of the path. Finally, to produce a complete results visualization of the MOP and the final 3D trajectory, the architecture was implemented in a simulation with Matlab/Simulink/flightGear.

Effective accuracy of stereoelectroencephalography: robotic 3D versus Talairach orthogonal approaches.

Stereoelectroencephalography (SEEG) was first developed in the 1950s by Jean Talairach using 2D angiography and a frame-based, orthogonal approach through a metallic grid. Since then, various other frame-based and frameless techniques have been described. In this study the authors sought to compare the traditional orthogonal Talairach 2D angiographic approach with a frame-based 3D robotic procedure that included 3D angiographic interoperative imaging guidance. MRI was used for both procedures during surgery, but MRI preplanning was done only in the robotic 3D technique. All study patients suffered from drug-resistant focal epilepsy and were treated at the same center by the same neurosurgical team. Fifty patients who underwent the 3D robotic procedure were compared to the same number of historical controls who had previously been successfully treated with the Talairach orthogonal procedure. The effectiveness and absolute accuracy, as well as safety, of the two procedures were compared. Moreover, in the 3D robotic group, the reliability of the preoperative MRI to avoid vascular structures was evaluated by studying the rate of trajectory modification following the coregistration of the intraoperative 3D angiographic data onto the preoperative MRI-based trajectory plans. Effective accuracy (96.5% vs 13.7%) and absolute accuracy (1.15 mm vs 4.00 mm) were significantly higher in the 3D robotic group than in the Talairach orthogonal group. Both procedures showed excellent safety results (no major complications). The rate of electrode modification after 3D angiography was 43.8%, and it was highest for frontal and insular locations. The frame-based, 3D angiographic, robotic procedure described here provided better accuracy for SEEG implantations than the traditional Talairach approach. This study also highlights the potential safety advantage of trajectory planning using intraoperative frame-based 3D angiography over preoperative MRI alone.

A novel, adaptable, radiographically opaque, multi-plane continuous filament marker for optimizing tissue identification, radiation planning, and radiographic follow-up.

In breast cancer treatment, marking the tumor bed is an important aspect of the surgical component of therapy. Clear delineation of the tumor bed allows radiation oncologists a defined target for planning and delivering postoperative radiation therapy (XRT). Tumor bed marking also allows radiographic follow-up of the tumor bed on subsequent breast imaging. The aim of this assessment is to evaluate the ease and feasibility of utilizing a tumor bed filament marker (VeraFormÒ, Videra Surgical inc., USA) as a marker in post-operative benign surgical sites and malignant breast surgical tumor beds in breast cancer surgery. The filament marker is a novel radiopaque surgical filament that in lieu of clips and other markers is implanted in the surgical tumor bed during breast surgery. Following development of the filament marker, the researchers used breast phantoms and radiographic images to develop a series of geometric patterns of placement options that optimize comprehensive multi-plane radiographic interpretation of the exact tumor bed or surgical margin. Three breast surgeons at 3 separate institutions then used this filament as a continuous multi-plane marker in 20 patients during breast conservation surgery. In these patients, the filament marker was thus used to mark the tumor bed (breast cancer surgery) or surgical site (benign breast disease) instead of the more traditional devices such as clips or other metallic open framework devices. We then assessed 2 important factors related to this device; (I) the ease, feasibility, and accuracy of in vivo placement with oncoplastic and non-oncoplastic breast conservation surgery techniques; (II) the radiographic footprint this device left on standard imaging protocols of post-operative mammogram (MMG), computed tomography (CT) scan, breast magnetic resonance imaging (MRI) examinations, and ultrasounds (USs) for both routine follow-up imaging and for standard radiation planning. There were no adverse events reported with the use of this device. The cases were then reviewed by a multidisciplinary team that included the original surgeon, a breast radiologist, and radiation oncologist. Their unanimous evaluation was that the filament marker clearly delineated all sides and planes of the tumor bed (cancer surgery) or surgical site (benign disease). Regardless of surgical technique utilized, this information provided precise 3D guidance for radiation planning and delivery as well as radiographic follow-up. The surgeons involved reported that delineating the bed with the filament marker was a quick and easy procedure and did not interfere with performing the planned surgical technique. Radiologists, surgeons, and radiation oncologists found that the filament marker was not only radiographically opaque on CT and MMG, but also caused no significant artifact on CT, MRI, US, or MMG. The continuous multi-plane filament marker is a new device that fulfills the heretofore unmet need for safe and improved tumor bed and tissue site marking. It is an easy to place, non-palpable continuous multi-plane radiographic opaque tissue marker that seems to better delineate the tumor bed, regardless of type of breast surgery performed, while providing a more accurate 3D image for radiation planning and radiographic follow-up on MMG MRI, CT and US.

3D guidance for hypersonic reentry gliders based on analytical prediction

In order to give full play to the potential of hypersonic gliders to strike a longrange of targets and perform large lateral maneuvering missions, a three-dimensional guidance method is proposed on the basis of analytical predictions. We first construct an entry guidance model for a glider and derive the analytical solution for the trajectory based on Lyapunov's artificial small parameter method. Such an approach ensures high accuracy in the theoretical prediction of flight trajectory. Subsequently, we construct a three-dimensional (3D) flight corridor that satisfies multiple constraints including heat rate, dynamic pressure, overload, angle of attack, and bank angle. Furthermore, the flight profile and bank reversal strategy in the 3D flight corridor model are designed on the basis of the analytical solution of the flight trajectory considering both longitudinal flight range and lateral flight mobility requirements of the glider. In addition, the control commands of the angle of attack and bank angle are generated by tracking the profile of the flight. The method has been tested in three cases of guidance under short-, medium-, and long-range flights. The results show that it provides high prediction accuracy and strong self-adaptive capability for all the test cases. Our proposed method targets the design of a 3D flight profile in a 3D flight corridor. Furthermore, the method considers flight requirements in both the longitudinal and lateral directions, thus maximising the aircraft's ability to reach the target while maintaining high levels of flexibility and self-adaptive capability during the mission.

P916The effect of a novel, user-friendly, transcatheter edge-to-edge mitral valve repair device in a porcine model of mitral regurgitation

Abstract Objective A new technique has been devised to treat mitral regurgitation (MR) through the transapical route by replicating the edge-to-edge repair surgery. This system encompasses an easy-to-use leaflet clamp and a smaller-sized delivery system (14F–16F). We aimed to evaluate the effectiveness of this device in a porcine model of acute MR. Methods Acute MR was induced in 36 anesthetized porcine subjects by severing the major chordae supporting the corresponding segment of the leaflet. This device was then transapically implanted on the prolapsing segment under 3D epicardial echocardiographic guidance. All of the animals were killed 30 days after the procedure to verify the proper location of the implanted devices. Results Cutting the major chordae induced an eccentric MR jet (MR grade: 3+, 27.8%/4+, 72.2%) in all of the animals. Every single pig was then successfully implanted with one clamp. The duration of catheterization ranged from 18 to 40 minutes. Overt MR reduction was observed following the procedure through echocardiography; residual MR was mild in 8 cases, trivial in 19 cases, and absent in 9 cases. In terms of hemodynamic parameters, the mean and maximum mitral valve pressure gradients were increased significantly (p<0.01), but these values were less than 4 mmHg in all of the cases. Autopsy demonstrated that all but one device were precisely placed to clip the prolapsing segment of the mitral valve, and there was no evidence of thrombosis, thromboembolism or impairment of the cardiac structure. Table 1. Changes in hemodynamic parameters, cardiac size, and functional parameters after the procedure Preoperation Postoperation P value MR-maxA (mm2) 7.27±2.13 1.54±1.29 0.000 MVPG-max (mmHg) 1.95±0.47 3.66±0.62 0.000 MVPG-mean (mmHg) 0.87±0.31 1.7±0.28 0.000 LVEDD (mm) 46.08±2.85 46.44±3.53 0.239 LVESD (mm) 29.11±3.44 29.08±3.62 0.940 LVEF (%) 66.53±6.4 67.14±4.93 0.256 LAD (mm) 35.75±2.24 36.42±1.99 0.057 LAA (mm2) 12.95±2.22 12.64±1.55 0.301 Figure 1 Conclusions Transapical implantation of the novel mitral valve repair device is effective and safe in reducing acutely induced MR in pigs; thus, suggesting that it has great potential for clinical benefit in patients with MR. Acknowledgement/Funding Shanghai Science and Technology Committee

Optimal energy-based 4D guidance and control for terminal descent operations

This paper presents an energy-optimal guidance and control strategy for 4-dimensional (4D) Trajectory-Based Operations (TBO) in the descent phase, supporting the development of 4D Human-Machine Interface (HMI) formats. The vertical guidance strategy uses multi-phase optimal control techniques based on point-mass aircraft dynamics to determine an energy-optimal descent profile fulfilling prescribed time constraints, additionally generating a set of control inputs which can be passed to the control module. The control strategy is decomposed into attitude and time-and-energy (T&E) components. The attitude control module corrects for cross-track deviations from the nominal profile previously calculated by the guidance algorithm, while the T&E control module corrects for the along-track distance and total energy deviations from the nominal profile. A virtual energy term is introduced which allows the control module to compensate for time deviations from the 4D trajectory. The proposed T&E guidance and control modules are verified through a number of representative case studies, showing that the proposed guidance and control modules allow the aircraft to follow a T&E-optimal 4D trajectory and to recover from deviations in the initial energy states. A prototype HMI is subsequently introduced to present the recommended control inputs to the pilot, also supporting assisted energy management in 4D descent operations.

Combining Direct 3D Volume Rendering and Magnetic Particle Imaging to Advance Radiation-Free Real-Time 3D Guidance of Vascular Interventions.

Magnetic particle imaging (MPI) is a novel tomographic radiation-free imaging technique that combines high spatial resolution and real-time capabilities, making it a promising tool to guide vascular interventions. Immediate availability of 3D image data is a major advantage over the presently used digital subtraction angiography (DSA), but new methods for real-time image analysis and visualization are also required to take full advantage of the MPI properties. This laboratory study illustrates respective techniques by means of three different patient-specific 3D vascular flow models. The selected models corresponded to typical anatomical intervention sites. Routine patient cases and image data were selected, relevant vascular territories segmented, 3D models generated and then 3D-printed. Printed models were used to perform case-specific MPI imaging. The resulting MPI images, direct volume rendering (DVR)-based fast 3D visualization options, and their suitability to advance vascular interventions were evaluated and compared to conventional DSA. The experiments illustrated the feasibility and potential to enhance image interpretation during interventions by using MPI real-time volumetric imaging and problem-tailored DVR-based fast (approximately 30 frames/s) 3D visualization options. These options included automated viewpoint selection and cutaway views. The image enhancement potential is especially relevant for complex geometries (e.g., in the presence of superposed vessels). The unique features of the as-yet preclinical imaging modality MPI render it promising for guidance of vascular interventions. Advanced fast DVR could help to fulfill this promise by intuitive visualization of the 3D intervention scene in real time.

Radiation Dose in Prostatic Artery Embolization Using Cone-Beam CT and 3D Roadmap Software.

To evaluate the radiation dose in patients undergoing prostatic artery embolization (PAE) using cone-beam CT and 3-dimensional (3D) guidance software. In this single-center retrospective study, 100 patients with benign prostatic hyperplasia (mean prostate volume, 83.6 mL ± 44.2; 69.4 ± 9.6 years of age; body mass index, 26.5 ± 4.2) were treated using PAE between October 2016 and April 2018. Informed consent was obtained from all participants included in the study. All patients received at least 1 intraprocedural cone-beam CT per side for evaluation of the vessel anatomy and software rendering of 3D guidance for catheter guidance. Digital subtraction angiography (DSA) was performed in the distal branches only. The total dose area product (DAP), along with the DAP attributed to fluoroscopy, DSA, and cone-beam CT, were assessed. Bilateral embolization was achieved in 83 patients (83%). The average total DAP was 134.4 Gy ⋅ cm2 ± 69.5 (range, 44.7-410.9 Gy ⋅ cm2). Fluoroscopy, DSA, and cone-beam CT accounted for 35.5 Gy ⋅ cm2 ± 21.3 (range, 8.6-148.6 Gy ⋅ cm2) or 26.4% (percentage oftotal DAP), 58.2 Gy ⋅ cm2 ± 48.3 (range, 10.3-309.3 Gy ⋅ cm2) or 43.3%, and 40.7 Gy ⋅ cm2 ± 14.5 (range, 15.9-86.3 Gy ⋅ cm2) or 30.3%, respectively. Average procedure time was 89.4 ± 27.0 minutes, and the average fluoroscopy time was 30.9 ± 12.2 minutes. Intraprocedural cone-beam CT in combination with 3D guidance software allows for identification and catheterization of the prostatic artery in PAE. Furthermore, the results of this trial indicate that this study protocol may lead to a low overall radiation dose.

3D optimal defensive guidance strategy with safe distance

This work investigates the active defense problem wherein a target aircraft launches a defending missile (i.e. a defender) to intercept an attacking missile in three-dimensional (3D) space. The novelty of this work includes: adding a safe distance for the target, which protects the target from being influenced by defensive interception, and designing a new 3D defensive guidance strategy without linearization to meet different guidance requirements. The defensive guidance strategy combines the approach of analyzing 3D pursuit-evasion engagement and the optimal control to obtain the guidance law. The approach derives the analytical solutions of 3D pursuit-evasion engagement, and a fast algorithm to predict the trajectory of attacking missile is proposed based on these analytical solutions. The advantages of this guidance strategy include incorporation of the added safe distance requirement directly without hindering the ability of the optimal guidance law to meet other requirements, and straight-forward extension for advanced scenarios where multi-defenders intercept the attacking missile simultaneously from different directions. The performance of the 3D defensive guidance law is evaluated via simulations.

Two-dimensional-three-dimensional registration for fusion imaging is noninferior to three-dimensional- three-dimensional registration in infrarenal endovascular aneurysm repair

BackgroundFusion imaging is a tool for intraoperative three-dimensional (3D) guidance in endovascular aneurysm repair (EVAR). In many aortic centers, the registration for location is based on an intraoperative 3D dataset acquired by means of cone-beam computed tomography (3D-3D registration). Another registration method is based on two two-dimensional (2D) images (lateral and posteroanterior) acquired with the use of intraoperative fluoroscopy for registration with a computed tomographic angiogram (2D-3D registration). The aim of the present study was to compare 2D-3D registration with 3D-3D registration regarding noninferiority in accuracy and to describe radiation exposure and ease of use of both modalities. MethodsFrom December 2014 to September 2015, 50 sequentially enrolled patients received EVAR with the use of fusion imaging using 2D-3D registration. No adjustments were made until the first angiography with inserted stent graft. The deviation of fusion imaging to the actual position of the lower renal artery compared with digital subtraction angiography was measured. A historic cohort of 101 patients treated with EVAR and fusion imaging with 3D-3D registration (3D-3D cohort) served as the control group for this study. ResultsCraniocaudal deviation did not differ significantly (4.6 ± 4.4 mm in the 2D-3D cohort vs 3.6 ± 3.9 mm in the 3D-3D cohort; P = .17). The difference of the means was 1.05 mm with a 95% confidence interval of −2.45 to 0.34 and a P value for the noninferiority test of .0249, indicating that 2D-3D registration was noninferior in terms of a margin of δ = 2.5 mm. 2D-3D registration was significantly faster with significantly less additional radiation necessary: 0.45 ± 0.28 vs 45.7 ± 9.1 Gy·cm2 in the 3D-3D cohort (P < .001); 2.3 ± 1.3 vs 5.3 ± 4.3 minutes in the 3D-3D cohort (P < .001). ConclusionsFusion imaging during EVAR with the use of 2D-3D registration is feasible in routine EVAR. Our findings of two consecutive cohorts with the same clinical, hardware, and software setup used for the procedures underscore that the accuracy of 2D-3D registration is noninferior to that of a 3D-3D registration workflow, with advantages in terms of radiation exposure, intraoperative time demand, and ease of use.

Development and Clinical Validation of a 3D Ultrasound System for Permanent Breast Seed Implant Brachytherapy

Permanent Breast Seed Implant (PBSI) is a novel form of breast brachytherapy completed in a single 1-2h procedure. PBSI planning uses CT simulation and treatment involves implanting Pd-103 seeds in and around the breast seroma via needles inserted through a template and guided by free-hand 2D ultrasound. The seroma shape and size vary from CT images to ultrasound and currently neither 3D images nor real-time guidance are available for PBSI. A 3D ultrasound (3DUS) system has been developed to fulfill these needs. This study extends this work to validate the 3DUS clinical implementation in PBSI planning and delivery procedure.

3D-2D Image Registration in Virtual Long-Film Imaging: Application to Spinal Deformity Correction.

Intraoperative 2D virtual long-film (VLF) imaging is investigated for 3D guidance and confirmation of the surgical product in spinal deformity correction. Multi-slot-scan geometry (rather than a single-slot "topogram") is exploited to produce parallax views of the scene for accurate 3D colocalization from a single radiograph. The multi-slot approach uses additional angled collimator apertures to form fan-beams with disparate views (parallax) of anatomy and instrumentation and to extend field-of-view beyond the linear motion limits. Combined with a knowledge of surgical implants (pedicle screws and/or spinal rods modeled as "known components"), 3D-2D image registration is used to solve for pose estimates via optimization of image gradient correlation. Experiments were conducted in cadaver studies emulating the system geometry of the O-arm (Medtronic, Minneapolis MN). Experiments demonstrated feasibility of multi-slot VLF and quantified the geometric accuracy of 3D-2D registration using VLF acquisitions. Registration of pedicle screws from a single VLF yielded mean target registration error of (2.0±0.7) mm, comparable to the accuracy of surgical trackers and registration using multiple radiographs (e.g., AP and LAT). 3D-2D registration in a single VLF image offers a promising new solution for image guidance in spinal deformity correction. The ability to accurately resolve pose from a single view absolves workflow challenges of multiple-view registration and suggests application beyond spine surgery, such as reduction of long-bone fractures.

Preoperative planning of medial opening wedge high tibial osteotomy using 3D computer-aided design weight-bearing simulated guidance: Technique and preliminary result.

High tibial osteotomy (HTO) is an established treatment for uni-compartmental osteoarthritis with varus deformity in relatively active young patients with good knee mobility. The most important factor for success and low complications of HTO is the precise correction of osteotomy. The objective of this study was to evaluate the accuracy of pre-operative planning of open-wedge HTO using t3D computer-aided design (CAD) weight-bearing simulated guidance technique for the succession of surgery. Nineteen patients who met the inclusion criteria were recruited between July 2013 and June 2014. 3D CAD weight-bearing simulated guidance technique was obtained from standard anterior-posterior, lateral of hip-to-ankle full leg standing radiographs, and computed tomography (CT) scan provided the weight-bearing corrective axis of preoperative planning and predictive corrective mechanical axis value. Post-operative mechanical axis value was obtained after surgery. This comparative study between the predictive corrective, using 3D CAD weight-bearing simulated guidance technique, and post-operative mechanical axis value, analysed with t-test statistical analysis, showed the insignificant difference ( p > 0.05). We conclude that the 3D CAD weight-bearing simulated guidance technique has good accuracy as preoperative planning of open-wedge HTO for succession surgery.

C-Arm computed tomography (CACT)-guided balloon pulmonary angioplasty (BPA): Evaluation of patient safety and peri- and post-procedural complications.

To assess the frequency and severity of complications of balloon pulmonary angioplasty (BPA) using C-arm computed tomography (CACT) guidance. 266 consecutive interventions in 67 patients (42 females, mean age 66 ± 13 years) were included. Selective CACT was acquired prior to the intervention for three-dimensional (3D) guidance and to select appropriate balloon size based on the measured vessel diameter. Complications during and after the procedure, the need for further interventions and the impact on patient safety and outcome were assessed and categorised according to the SIR Classification System to Complications by Outcome (Grade A-F). Overall, 237 interventions were conducted without any complications (89.1%). Minor complications not requiring additional treatment occurred during or after 25 procedures (9.4%), including recurring dry cough in four patients during a total of 11 interventions (4.1%) (Grade A), three focal dissections of the targeted pulmonary artery (1.1%), four cases of pulmonary haemorrhage (1.5%), one case of reperfusion oedema (0.4%) and six cases of post-interventional short-term hemoptysis (2.3%) (Grade B). Four cases of major complications requiring additional treatment were observed (1.5%): one case of pulmonary haemorrhage (0.4%) and two cases of post-interventional haemoptysis (0.8%), all resolved after medical therapy without requiring further intervention, and one case of atrial tachycardia induced during catheterisation, subsequently requiring pharmacological cardioversion (0.4%) (Grade C). No fatal or life-threatening peri- or post-interventional complications or mortality were observed (Grade D-F). BPA performed under CACT guidance appears to be a safe procedure with a low risk of severe complications. • CACT guidance of BPA is safe and successful. • CACT-guided BPA procedures have a low complication profile. • CACT guidance is a valuable tool to navigate BPA.

Patient-specific immersive HPB surgery simulation using OsiriX-based 3D printing, virtual reality, augmented reality and mixed reality

Image guided virtual surgical planning 3D technology has improved surgical efficiency and precision. To promote these accuracy and usability, we developed new osirix-based surgical simulation system using virtual reality (VR), augmented reality (AR), and mixed reality (MR) with 3D replicating technology. We developed a spatial surgical simulation system using medical images by interactive superimposing 3D hologram in an actual space. Interactive stereo display was used for the existence of an interaction between the users and stereo images of the patient's anatomy depicted on the display in the form of tracking the useŕs head and hand/arm position. We also developed new technology of bio-texture modeling by multi-material 3D printing. Based on MDCT, regions of interest were segmented using DICOM viewer OsiriX application. After generating an 3D surface, the inkjet 3D printer created a 3D multi-material organ replica. Our system is integrated to 3D organ replication and surgical guidance, obtained augmented tangibility in surgical simulation and navigation. It could manipulate the spatial attributes of the virtual and real printed organs, which can enhance spatial reasoning and augmented tangibility. Permitting the physician to manipulate virtual organs also allowed for the creation of a sense of spatial relations among elements in the display via proprioception. The tangible organ replication with spatial surgical image-guided simulation provided better anatomical reference tool as a tailor-made guidance in laparoscopic surgery, and contribute to medical safety and accuracy, less-invasiveness and improvement of the medical education.

Radiothérapie guidée par l’image des cancers ORL

Intensity-modulated radiotherapy, combined with chemotherapy, is the recommended treatment of locally advanced head and neck carcinoma, as a definitive treatment or as an adjuvant treatment following surgery. This technique offers the ability to sculpt the dose closely to the tumor volume. With this close conformity, it is essential to ensure that every day during the treatment the patient position and anatomy are similar to those at the time of treatment planning. Inevitably, there will be uncertainties introduced in this process and a planning target volume margins are added around the tumour volume to compensate for these uncertainties. Various imaging technologies have been integrated with linear accelerators to deal with patient position and potentially reduce the margins. This forms the foundations of image-guided radiotherapy. In patients with head and neck carcinoma systematic and random set-up uncertainties are frequent. The 3D volumetric image guidance systems are efficient to reduce these uncertainties. After a summary about the different sources of uncertainties, this review will present successively the different techniques of image-guided radiotherapy for head and neck carcinomas, along with their advantages and limitations. Then we will focus on the methods used to reduce the set-up uncertainties and finally discuss the concept of adaptive radiotherapy and its application in clinical practice.

Wednesday, September 26, 2018 1:00 PM – 2:00 PM Navigation and Intraoperative Monitoring: 49. Novel technology for C-arm based pedicle navigation

Wednesday, September 26, 2018 1:00 PM – 2:00 PM Navigation and Intraoperative Monitoring: 49. Novel technology for C-arm based pedicle navigation

Three-Dimensional Compared with Two-Dimensional Preoperative Planning of Corrective Osteotomy for Extra-Articular Distal Radial Malunion: A Multicenter Randomized Controlled Trial.

Malunion is the most frequent complication seen after a fracture of the distal end of the radius. The primary aim of this study was to compare patient-reported outcome measures (PROMs) after corrective osteotomy for malunited distal radial fractures with and without 3-dimensional (3D) planning and use of patient-specific surgical guides. From September 2010 to May 2015, 40 adult patients with a symptomatic extra-articular malunited distal radial fracture were randomized to 3D computer-assisted planning or conventional 2-dimensional (2D) planning for corrective osteotomy. The primary outcome was the Disabilities of the Arm, Shoulder and Hand (DASH) score. Secondary outcomes included the Patient-Rated Wrist Evaluation (PRWE) score, pain and satisfaction scores, grip strength, and radiographic measurements at 3, 6, and 12 months postoperatively. From baseline to 12 months of follow-up, the reduction in the mean DASH score was -30.7 ± 18.7 points for the 3D planning group compared with -20.1 ± 17.8 points for 2D planning (p = 0.103). Secondary functional outcome by means of the PRWE resulted in a similar reduction of -34.4 ± 22.9 points for the 3D planning group compared with -26.6 ± 18.3 points for the 2D planning group (p = 0.226). There were no significant differences in pain, satisfaction, range of motion, and grip strength. Radiographic analysis showed significant differences in the mean residual volar angulation (by 3.3°; p = 0.04) and radial inclination (by 2.7°; p = 0.028) compared with the templated side, in favor of 3D planning and guidance. The duration of preoperative planning and surgery as well as complication rates were comparable. Although there was a trend toward a minimal clinically important difference in PROMs in favor of 3D computer-assisted guidance for corrective osteotomy of extra-articular distal radial malunion, it did not attain significance because of (post hoc) insufficient power. Despite the challenge of feasibility, a trial of large magnitude is warranted to draw definitive conclusions regarding clinical advantages of this advanced, more expensive technology. Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.