Three-dimensional ultrasound image-guided robotic system for accurate microwave coagulation of malignant liver tumours

Background The further application of conventional ultrasound (US) image-guided microwave (MW) ablation of liver cancer is often limited by two-dimensional (2D) imaging, inaccurate needle placement and the resulting skill requirement. The three-dimensional (3D) image-guided robotic-assisted system provides an appealing alternative option, enabling the physician to perform consistent, accurate therapy with improved treatment effectiveness. Methods Our robotic system is constructed by integrating an imaging module, a needle-driven robot, a MW thermal field simulation module, and surgical navigation software in a practical and user-friendly manner. The robot executes precise needle placement based on the 3D model reconstructed from freehand-tracked 2D B-scans. A qualitative slice guidance method for fine registration is introduced to reduce the placement error caused by target motion. By incorporating the 3D MW specific absorption rate (SAR) model into the heat transfer equation, the MW thermal field simulation module determines the MW power level and the coagulation time for improved ablation therapy. Two types of wrists are developed for the robot: a ‘remote centre of motion’ (RCM) wrist and a non-RCM wrist, which is preferred in real applications. Results The needle placement accuracies were < 3 mm for both wrists in the mechanical phantom experiment. The target accuracy for the robot with the RCM wrist was improved to 1.6 ± 1.0 mm when real-time 2D US feedback was used in the artificial-tissue phantom experiment. By using the slice guidance method, the robot with the non-RCM wrist achieved accuracy of 1.8 ± 0.9 mm in the ex vivo experiment; even target motion was introduced. In the thermal field experiment, a 5.6% relative mean error was observed between the experimental coagulated neurosis volume and the simulation result. Conclusion The proposed robotic system holds promise to enhance the clinical performance of percutaneous MW ablation of malignant liver tumours. Copyright © 2010 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78054/1/313_ftp.pd

Advanced Endoscopic Navigation:Surgical Big Data,Methodology,and Applications

随着科学技术的飞速发展，健康与环境问题日益成为人类面临的最重大问题之一。信息科学、计算机技术、电子工程与生物医学工程等学科的综合应用交叉前沿课题，研究现代工程技术方法，探索肿瘤癌症等疾病早期诊断、治疗和康复手段。本论文综述了计算机辅助微创外科手术导航、多模态医疗大数据、方法论及其临床应用：从引入微创外科手术导航概念出发，介绍了医疗大数据的术前与术中多模态医学成像方法、阐述了先进微创外科手术导航的核心流程包括计算解剖模型、术中实时导航方案、三维可视化方法及交互式软件技术，归纳了各类微创外科手术方法的临床应用。同时，重点讨论了全球各种手术导航技术在临床应用中的优缺点，分析了目前手术导航领域内的最新技术方法。在此基础上，提出了微创外科手术方法正向数字化、个性化、精准化、诊疗一体化、机器人化以及高度智能化的发展趋势。【Abstract】Interventional endoscopy (e.g., bronchoscopy, colonoscopy, laparoscopy, cystoscopy) is a widely performed procedure that involves either diagnosis of suspicious lesions or guidance for minimally invasive surgery in a variety of organs within the body cavity. Endoscopy may also be used to guide the introduction of certain items (e.g., stents) into the body. Endoscopic navigation systems seek to integrate big data with multimodal information (e.g., computed tomography, magnetic resonance images, endoscopic video sequences, ultrasound images, external trackers) relative to the patient's anatomy, control the movement of medical endoscopes and surgical tools, and guide the surgeon's actions during endoscopic interventions. Nevertheless, it remains challenging to realize the next generation of context-aware navigated endoscopy. This review presents a broad survey of various aspects of endoscopic navigation, particularly with respect to the development of endoscopic navigation techniques. First, we investigate big data with multimodal information involved in endoscopic navigation. Next, we focus on numerous methodologies used for endoscopic navigation. We then review different endoscopic procedures in clinical applications. Finally, we discuss novel techniques and promising directions for the development of endoscopic navigation.X.L. acknowledges funding from the Fundamental Research Funds for the Central Universities. T.M.P. acknowledges funding from the Canadian Foundation for Innovation, the Canadian Institutes for Health Research, the National Sciences and Engineering Research Council of Canada, and a grant from Intuitive Surgical Inc

SURGICAL NAVIGATION AND AUGMENTED REALITY FOR MARGINS CONTROL IN HEAD AND NECK CANCER

I tumori maligni del distretto testa-collo rappresentano un insieme di lesioni dalle diverse caratteristiche patologiche, epidemiologiche e prognostiche. Per una porzione considerevole di tali patologie, l’intervento chirurgico finalizzato all’asportazione completa del tumore rappresenta l’elemento chiave del trattamento, quand’anche esso includa altre modalità quali la radioterapia e la terapia sistemica. La qualità dell’atto chirurgico ablativo è pertanto essenziale al fine di garantire le massime chance di cura al paziente. Nell’ambito della chirurgia oncologica, la qualità delle ablazioni viene misurata attraverso l’analisi dello stato dei margini di resezione. Oltre a rappresentare un surrogato della qualità della resezione chirurgica, lo stato dei margini di resezione ha notevoli implicazioni da un punto di vista clinico e prognostico. Infatti, il coinvolgimento dei margini di resezione da parte della neoplasia rappresenta invariabilmente un fattore prognostico sfavorevole, oltre che implicare la necessità di intensificare i trattamenti postchirurgici (e.g., ponendo indicazione alla chemioradioterapia adiuvante), comportando una maggiore tossicità per il paziente. La proporzione di resezioni con margini positivi (i.e., coinvolti dalla neoplasia) nel distretto testa-collo è tra le più elevate in ambito di chirurgia oncologica. In tale contesto si pone l’obiettivo del dottorato di cui questa tesi riporta i risultati. Le due tecnologie di cui si è analizzata l’utilità in termini di ottimizzazione dello stato dei margini di resezione sono la navigazione chirurgica con rendering tridimensionale e la realtà aumentata basata sulla videoproiezione di immagini. Le sperimentazioni sono state svolte parzialmente presso l’Università degli Studi di Brescia, parzialmente presso l’Azienda Ospedale Università di Padova e parzialmente presso l’University Health Network (Toronto, Ontario, Canada). I risultati delle sperimentazioni incluse in questo elaborato dimostrano che l'impiego della navigazione chirurgica con rendering tridimensionale nel contesto di procedure oncologiche ablative cervico-cefaliche risulta associata ad un vantaggio significativo in termini di riduzione della frequenza di margini positivi. Al contrario, le tecniche di realtà aumentata basata sulla videoproiezione, nell'ambito della sperimentazione preclinica effettuata, non sono risultate associate a vantaggi sufficienti per poter considerare tale tecnologia per la traslazione clinica.Head and neck malignancies are an heterogeneous group of tumors. Surgery represents the mainstay of treatment for the large majority of head and neck cancers, with ablation being aimed at removing completely the tumor. Radiotherapy and systemic therapy have also a substantial role in the multidisciplinary management of head and neck cancers. The quality of surgical ablation is intimately related to margin status evaluated at a microscopic level. Indeed, margin involvement has a remarkably negative effect on prognosis of patients and mandates the escalation of postoperative treatment by adding concomitant chemotherapy to radiotherapy and accordingly increasing the toxicity of overall treatment. The rate of margin involvement in the head and neck is among the highest in the entire field of surgical oncology. In this context, the present PhD project was aimed at testing the utility of 2 technologies, namely surgical navigation with 3-dimensional rendering and pico projector-based augmented reality, in decreasing the rate of involved margins during oncologic surgical ablations in the craniofacial area. Experiments were performed in the University of Brescia, University of Padua, and University Health Network (Toronto, Ontario, Canada). The research activities completed in the context of this PhD course demonstrated that surgical navigation with 3-dimensional rendering confers a higher quality to oncologic ablations in the head and neck, irrespective of the open or endoscopic surgical technique. The benefits deriving from this implementation come with no relevant drawbacks from a logistical and practical standpoint, nor were major adverse events observed. Thus, implementation of this technology into the standard care is the logical proposed step forward. However, the genuine presence of a prognostic advantage needs longer and larger study to be formally addressed. On the other hand, pico projector-based augmented reality showed no sufficient advantages to encourage translation into the clinical setting. Although observing a clear practical advantage deriving from the projection of osteotomy lines onto the surgical field, no substantial benefits were measured when comparing this technology with surgical navigation with 3-dimensional rendering. Yet recognizing a potential value of this technology from an educational standpoint, the performance displayed in the preclinical setting in terms of surgical margins optimization is not in favor of a clinical translation with this specific aim

Intraoperative Navigation Systems for Image-Guided Surgery

Recent technological advancements in medical imaging equipment have resulted in a dramatic improvement of image accuracy, now capable of providing useful information previously not available to clinicians. In the surgical context, intraoperative imaging provides a crucial value for the success of the operation. Many nontrivial scientific and technical problems need to be addressed in order to efficiently exploit the different information sources nowadays available in advanced operating rooms. In particular, it is necessary to provide: (i) accurate tracking of surgical instruments, (ii) real-time matching of images from different modalities, and (iii) reliable guidance toward the surgical target. Satisfying all of these requisites is needed to realize effective intraoperative navigation systems for image-guided surgery. Various solutions have been proposed and successfully tested in the field of image navigation systems in the last ten years; nevertheless several problems still arise in most of the applications regarding precision, usability and capabilities of the existing systems. Identifying and solving these issues represents an urgent scientific challenge. This thesis investigates the current state of the art in the field of intraoperative navigation systems, focusing in particular on the challenges related to efficient and effective usage of ultrasound imaging during surgery. The main contribution of this thesis to the state of the art are related to: Techniques for automatic motion compensation and therapy monitoring applied to a novel ultrasound-guided surgical robotic platform in the context of abdominal tumor thermoablation. Novel image-fusion based navigation systems for ultrasound-guided neurosurgery in the context of brain tumor resection, highlighting their applicability as off-line surgical training instruments. The proposed systems, which were designed and developed in the framework of two international research projects, have been tested in real or simulated surgical scenarios, showing promising results toward their application in clinical practice

InterNAV3D: A Navigation Tool for Robot-Assisted Needle-Based Intervention for the Lung

Lung cancer is one of the leading causes of cancer deaths in North America. There are recent advances in cancer treatment techniques that can treat cancerous tumors, but require a real-time imaging modality to provide intraoperative assistive feedback. Ultrasound (US) imaging is one such modality. However, while its application to the lungs has been limited because of the deterioration of US image quality (due to the presence of air in the lungs); recent work has shown that appropriate lung deflation can help to improve the quality sufficiently to enable intraoperative, US-guided robotics-assisted techniques to be used. The work described in this thesis focuses on this approach. The thesis describes a project undertaken at Canadian Surgical Technologies and Advanced Robotics (CSTAR) that utilizes the image processing techniques to further enhance US images and implements an advanced 3D virtual visualization software approach. The application considered is that for minimally invasive lung cancer treatment using procedures such as brachytherapy and microwave ablation while taking advantage of the accuracy and teleoperation capabilities of surgical robots, to gain higher dexterity and precise control over the therapy tools (needles and probes). A number of modules and widgets are developed and explained which improve the visibility of the physical features of interest in the treatment and help the clinician to have more reliable and accurate control of the treatment. Finally the developed tools are validated with extensive experimental evaluations and future developments are suggested to enhance the scope of the applications

The Challenge of Augmented Reality in Surgery

Imaging has revolutionized surgery over the last 50 years. Diagnostic imaging is a key tool for deciding to perform surgery during disease management; intraoperative imaging is one of the primary drivers for minimally invasive surgery (MIS), and postoperative imaging enables effective follow-up and patient monitoring. However, notably, there is still relatively little interchange of information or imaging modality fusion between these different clinical pathway stages. This book chapter provides a critique of existing augmented reality (AR) methods or application studies described in the literature using relevant examples. The aim is not to provide a comprehensive review, but rather to give an indication of the clinical areas in which AR has been proposed, to begin to explain the lack of clinical systems and to provide some clear guidelines to those intending pursue research in this area

Intra-Operative Needle Tracking Using Optical Shape Sensing Technology

RÉSUMÉ Contexte : Les métastases hépatiques colorectales sont la principale cause de décès liée au cancer du foie dans le monde. Au cours de la dernière décennie, il a été démontré que l’ablation par radiofréquence (RFA, pour radiofrequency ablation) est une méthode de traitement percutané très efficace contre ce type de métastases. Cela dit, un positionnement précis de l’embout de l’aiguille utilisé en RFA est essentiel afin de se départir adéquatement de la totalité des cellules cancéreuses. Une technologie prometteuse pour obtenir la forme et la position de l’aiguille en temps réel est basée sur l’utilisation de réseaux de Bragg (FBG, pour fiber Bragg grating) à titre de senseur de contrainte. En effet, ce type de senseurs a une vitesse d’acquisition allant jusqu’à 20 kHz, ce qui est suffisamment rapide pour permettre des applications de guidage en temps réel. Méthode : Les travaux présentés au sein de ce mémoire décrivent le développement d’une technologie, compatible aux systèmes d’imageries par résonance magnétique (IRM), permettant d’effectuer le suivi de la forme de l’aiguille utilisée en RFA. Premièrement, trois fibres contenant une série de réseaux de Bragg ont été collées dans une géométrie spécifique et intégrées à l’intérieur d’une aiguille 20G-150 mm. Ensuite, un algorithme de reconstruction de forme tridimensionnelle a été développé, basé sur les mesures de translation spectrales des FBGs acquises en temps réel durant le guidage de l’aiguille. La position du bout de l’aiguille ainsi que la forme tridimensionnelle complète de celle-ci ont été représentées et comparées à la position de la zone ciblée à la suite d’une simple méthode de calibration. Finalement, nous avons validé notre système de navigation en effectuant une série d’expériences in vitro. La précision du système de reconstruction tridimensionnelle de la forme et de l’orientation de l’aiguille a été évaluée en utilisant deux caméras positionnées perpendiculairement de manière à connaitre la position de l’aiguille dans le système d’axes du laboratoire. L’évaluation de la précision au bout de l’aiguille a quant à elle été faite en utilisant des fantômes précisément conçus à cet effet. Finalement, des interventions guidées en IRM ont été testées et comparées au système de navigation électromagnétique NDI Aurora (EMTS, pour Electromagnétic tracking system) par le biais du FRE (fiducial registration error) et du TRE (target registration error). Résultats: Lors de nos premières expériences in vitro, la précision obtenue quant à la position du bout de l’aiguille était de 0,96 mm pour une déflexion allant jusqu’à ±10,68 mm. À titre comparatif, le système d’Aurora a une précision de 0.84 mm dans des circonstances similaires. Les résultats obtenus lors de nos seconds tests ont démontré que l’erreur entre la position réelle du bout de l’aiguille et la position fournie par notre système de reconstruction de forme est de 1,04 mm, alors qu’elle est de 0,82 mm pour le EMTS d’Aurora. Pour ce qui est de notre dispositif, cette erreur est proportionnelle à l’amplitude de déflexion de l’aiguille, contrairement à l’EMTS pour qui l’erreur demeure relativement constante. La dernière expérience a été effectuée à l’aide d’un fantôme en gélatine, pour laquelle nous avons obtenu un TRE de 1,19 mm pour notre système basé sur les FBG et de 1.06 mm pour le système de navigation par senseurs électromagnétiques (EMTS). Les résultats démontrent que l’évaluation du FRE est similaire pour les deux approches. De plus, l’information fournie par les caméras permet d’estimer la précision de notre dispositif en tout point le long de l’aiguille. Conclusion : En analysant et en interprétant les résultats obtenus lors de nos expériences in vitro, nous pouvons conclure que la précision de notre système de navigation basé sur les FBG est bien adaptée pour l’évaluation de la position du bout et la forme de l’aiguille lors d’interventions RFA des tumeurs du foie. La précision de notre système de navigation est fortement comparable avec celle du système basé sur des senseurs électromagnétiques commercialisé par Aurora. L’erreur obtenue par notre système est attribuable à un mauvais alignement des réseaux de Bragg par rapport au plan associé à la région sensorielle et aussi à la différence entre le diamètre des fibres et celui de la paroi interne de l’aiguille.----------ABSTRACT Background: Colorectal liver metastasis is the leading cause of liver cancer death in the world. In the past decade, radiofrequency ablation (RFA) has proven to be an effective percutaneous treatment modality for the treatment of metastatic hepatic cancer. Accurate needle tip placement is essential for RFA of liver tumors. A promising technology to obtain the real-time information of the shape of the needle is by using fiber Bragg grating (FBG) sensors at high frequencies (up to 20 kHz). Methods: In this thesis work, we developed an MR-compatible needle tracking technology designed for RFA procedures in liver cancer. At first, three fibers each containing a series of FBGs were glued together and integrated inside a 20G-150 mm needle. Then a three-dimensional needle shape reconstruction algorithm was developed, based on the FBG measurements collected in real-time during needle guidance. The tip position and shape of the reconstructed 3D needle model were represented with respect to the target defined in the image space by performing a fiducial-based registration. Finally, we validated our FBG-based needle navigation by doing a series of in-vitro experiments. The shape of the 3D reconstructed needle was compared to measurements obtained from camera images. In addition, the needle tip accuracy was assessed on the ground-truth phantoms. Finally, MRI guided intervention was tested and compared to an NDI Aurora EM tracking system (EMTS) in terms of fiducial registration error (FRE) and target registration error (TRE). Results: In our first in-vitro experiment, the tip tracking accuracy of our FBG tracking system was of 0.96 mm for the maximum tip deflection of up to ±10.68 mm, while the tip tracking accuracy of the Aurora system for the similar test was 0.84 mm. Results obtained from the second in-vitro experiment demonstrated tip tracking accuracy of 1.04 mm and 0.82 mm for our FBG tracking system and Aurora EMTS, respectively for the maximum tip deflection of up to ±16.83 mm. The tip tracking error in the developed FBG-based system reduced linearly with decreasing tip deflection, while the error was similar but randomly varying for the EMTS. The last experiment was done with a gel phantom, yielding a TRE of 1.19 mm and 1.06 mm for the FBG and EM tracking, respectively. Results showed that across all experiments, the computed FRE of both tracking systems was similar. Moreover, actual shape information obtained from the camera images ensured the shape accuracy of our FBG-based needle shape model. Conclusion: By analyzing and interpreting the results obtained from the in-vitro experiments, we conclude that the accuracy of our FBG-based tracking system is suitable for needle tip detection in RFA of liver tumors. The accuracy of our tracking system is nearly comparable to that of the Aurora EMTS. The error given by our tracking system is attributed to the misalignment of the FBG sensors in a single axial plane and also to the gap between the needle's inner wall and the fibers inside