Medical robots with potential applications in participatory and opportunistic remote sensing: A review

Among numerous applications of medical robotics, this paper concentrates on the design, optimal use and maintenance of the related technologies in the context of healthcare, rehabilitation and assistive robotics, and provides a comprehensive review of the latest advancements in the foregoing field of science and technology, while extensively dealing with the possible applications of participatory and opportunistic mobile sensing in the aforementioned domains. The main motivation for the latter choice is the variety of such applications in the settings having partial contributions to functionalities such as artery, radiosurgery, neurosurgery and vascular intervention. From a broad perspective, the aforementioned applications can be realized via various strategies and devices benefiting from detachable drives, intelligent robots, human-centric sensing and computing, miniature and micro-robots. Throughout the paper tens of subjects, including sensor-fusion, kinematic, dynamic and 3D tissue models are discussed based on the existing literature on the state-of-the-art technologies. In addition, from a managerial perspective, topics such as safety monitoring, security, privacy and evolutionary optimization of the operational efficiency are reviewed

A Sensorized Instrument for Minimally Invasive Surgery for the Measurement of Forces during Training and Surgery: Development and Applications

The reduced access conditions present in Minimally Invasive Surgery (MIS) affect the feel of interaction forces between the instruments and the tissue being treated. This loss of haptic information compromises the safety of the procedure and must be overcome through training. Haptics in MIS is the subject of extensive research, focused on establishing force feedback mechanisms and developing appropriate sensors. This latter task is complicated by the need to place the sensors as close as possible to the instrument tip, as the measurement of forces outside of the patient\u27s body does not represent the true tool--tissue interaction. Many force sensors have been proposed, but none are yet available for surgery. The objectives of this thesis were to develop a set of instruments capable of measuring tool--tissue force information in MIS, and to evaluate the usefulness of force information during surgery and for training and skills assessment. To address these objectives, a set of laparoscopic instruments was developed that can measure instrument position and tool--tissue interaction forces in multiple degrees of freedom. Different design iterations and the work performed towards the development of a sterilizable instrument are presented. Several experiments were performed using these instruments to establish the usefulness of force information in surgery and training. The results showed that the combination of force and position information can be used in the development of realistic tissue models or haptic interfaces specifically designed for MIS. This information is also valuable in order to create tactile maps to assist in the identification of areas of different stiffness. The real-time measurement of forces allows visual force feedback to be presented to the surgeon. When applied to training scenarios, the results show that experience level correlates better with force-based metrics than those currently used in training simulators. The proposed metrics can be automatically computed, are completely objective, and measure important aspects of performance. The primary contribution of this thesis is the design and development of highly versatile instruments capable of measuring force and position during surgery. A second contribution establishes the importance and usefulness of force data during skills assessment, training and surgery

Design of Novel Sensors and Instruments for Minimally Invasive Lung Tumour Localization via Palpation

Minimally Invasive Thoracoscopic Surgery (MITS) has become the treatment of choice for lung cancer. However, MITS prevents the surgeons from using manual palpation, thereby often making it challenging to reliably locate the tumours for resection. This thesis presents the design, analysis and validation of novel tactile sensors, a novel miniature force sensor, a robotic instrument, and a wireless hand-held instrument to address this limitation. The low-cost, disposable tactile sensors have been shown to easily detect a 5 mm tumour located 10 mm deep in soft tissue. The force sensor can measure six degrees of freedom forces and torques with temperature compensation using a single optical fiber. The robotic instrument is compatible with the da Vinci surgical robot and allows the use of tactile sensing, force sensing and ultrasound to localize the tumours. The wireless hand-held instrument allows the use of tactile sensing in procedures where a robot is not available

Enabling technologies for MRI guided interventional procedures

This dissertation addresses topics related to developing interventional assistant devices for Magnetic Resonance Imaging (MRI). MRI can provide high-quality 3D visualization of target anatomy and surrounding tissue, but the benefits can not be readily harnessed for interventional procedures due to difficulties associated with the use of high-field (1.5T or greater) MRI. Discussed are potential solutions to the inability to use conventional mecha- tronics and the confined physical space in the scanner bore. This work describes the development of two apparently dissimilar systems that repre- sent different approaches to the same surgical problem - coupling information and action to perform percutaneous (through the skin) needle placement with MR imaging. The first system addressed takes MR images and projects them along with a surgical plan directly on the interventional site, thus providing in-situ imaging. With anatomical images and a corresponding plan visible in the appropriate pose, the clinician can use this information to perform the surgical action. My primary research effort has focused on a robotic assistant system that overcomes the difficulties inherent to MR-guided procedures, and promises safe and reliable intra-prostatic needle placement inside closed high-field MRI scanners. The robot is a servo pneumatically operated automatic needle guide, and effectively guides needles under real- time MR imaging. This thesis describes development of the robotic system including requirements, workspace analysis, mechanism design and optimization, and evaluation of MR compatibility. Further, a generally applicable MR-compatible robot controller is de- veloped, the pneumatic control system is implemented and evaluated, and the system is deployed in pre-clinical trials. The dissertation concludes with future work and lessons learned from this endeavor

Using High-Level Processing of Low-Level Signals to Actively Assist Surgeons with Intelligent Surgical Robots

Robotic surgical systems are increasingly used for minimally-invasive surgeries. As such, there is opportunity for these systems to fundamentally change the way surgeries are performed by becoming intelligent assistants rather than simply acting as the extension of surgeons' arms. As a step towards intelligent assistance, this thesis looks at ways to represent different aspects of robot-assisted surgery (RAS). We identify three main components: the robot, the surgeon actions, and the patient scene dynamics. Traditional learning algorithms in these domains are predominantly supervised methods. This has several drawbacks. First many of these domains are non-categorical, like how soft-tissue deforms. This makes labeling difficult. Second, surgeries vary greatly. Estimation of the robot state may be affected by how the robot is docked and cable tensions in the instruments. Estimation of the patient anatomy and its dynamics are often inaccurate, and in any case, may change throughout a surgery. To obtain the most accurate information, these aspects must be learned during the procedure. This limits the amount of labeling that could be done. On the surgeon side, different surgeons may perform the same procedure differently and the algorithm should provide personalized estimations for surgeons. All of these considerations motivated the use of self-supervised learning throughout this thesis. We first build a representation of the robot system. In particular, we looked at learning the dynamics model of the robot. We evaluate the model by using it to estimate forces. Once we can estimate forces in free space, we extend the algorithm to take into account patient-specific interactions, namely with the trocar and the cannula seal. Accounting for surgery-specific interactions is possible because our method does not require additional sensors and can be trained in less than five minutes, including time for data collection. Next, we use cross-modal training to understand surgeon actions by looking at the bottleneck layer when mapping video to kinematics. This should contain information about the latent space of surgeon-actions, while discarding some medium-specific information about either the video or the kinematics. Lastly, to understand the patient scene, we start with modeling interactions between a robot instrument and a soft-tissue phantom. Models are often inaccurate due to imprecise material parameters and boundary conditions, particularly in clinical scenarios. Therefore, we add a depth camera to observe deformations to correct the results of simulations. We also introduce a network that learns to simulate soft-tissue deformation from physics simulators in order to speed up the estimation. We demonstrate that self-supervised learning can be used for understanding each part of RAS. The representations it learns contain information about signals that are not directly measurable. The self-supervised nature of the methods presented in this thesis lends itself well to learning throughout a surgery. With such frameworks, we can overcome some of the main barriers to adopting learning methods in the operating room: the variety in surgery and the difficulty in labeling enough training data for each case

Augmented Reality Assistance for Surgical Interventions using Optical See-Through Head-Mounted Displays

Augmented Reality (AR) offers an interactive user experience via enhancing the real world environment with computer-generated visual cues and other perceptual information. It has been applied to different applications, e.g. manufacturing, entertainment and healthcare, through different AR media. An Optical See-Through Head-Mounted Display (OST-HMD) is a specialized hardware for AR, where the computer-generated graphics can be overlaid directly onto the user's normal vision via optical combiners. Using OST-HMD for surgical intervention has many potential perceptual advantages. As a novel concept, many technical and clinical challenges exist for OST-HMD-based AR to be clinically useful, which motivates the work presented in this thesis. From the technical aspects, we first investigate the display calibration of OST-HMD, which is an indispensable procedure to create accurate AR overlay. We propose various methods to reduce the user-related error, improve robustness of the calibration, and remodel the calibration as a 3D-3D registration problem. Secondly, we devise methods and develop hardware prototype to increase the user's visual acuity of both real and virtual content through OST-HMD, to aid them in tasks that require high visual acuity, e.g. dental procedures. Thirdly, we investigate the occlusion caused by the OST-HMD hardware, which limits the user's peripheral vision. We propose to use alternative indicators to remind the user of unattended environment motion. From the clinical perspective, we identified many clinical use cases where OST-HMD-based AR is potentially helpful, developed applications integrated with current clinical systems, and conducted proof-of-concept evaluations. We first present a "virtual monitor'' for image-guided surgery. It can replace real radiology monitors in the operating room with easier user control and more flexibility in positioning. We evaluated the "virtual monitor'' for simulated percutaneous spine procedures. Secondly, we developed ARssist, an application for the bedside assistant in robotic surgery. The assistant can see the robotic instruments and endoscope within the patient body with ARssist. We evaluated the efficiency, safety and ergonomics of the assistant during two typical tasks: instrument insertion and manipulation. The performance for inexperienced users is significantly improved with ARssist, and for experienced users, the system significantly enhanced their confidence level. Lastly, we developed ARAMIS, which utilizes real-time 3D reconstruction and visualization to aid the laparoscopic surgeon. It demonstrates the concept of "X-ray see-through'' surgery. Our preliminary evaluation validated the application via a peg transfer task, and also showed significant improvement in hand-eye coordination. Overall, we have demonstrated that OST-HMD based AR application provides ergonomic improvements, e.g. hand-eye coordination. In challenging situations or for novice users, the improvements in ergonomic factors lead to improvement in task performance. With continuous effort as a community, optical see-through augmented reality technology will be a useful interventional aid in the near future

Aerospace Medicine and Biology: A cumulative index to the 1974 issues of a continuing bibliography

This publication is a cumulative index to the abstracts contained in supplements 125 through 136 of Aerospace Medicine and Biology: A Continuing Bibliography. It includes three indexes--subject, personal author, and corporate source

Sensores em fibra ótica para o estudo biomecânico do disco intervertebral

Doutoramento em Engenharia MecânicaO presente trabalho teve como objetivo principal estudar o comportamento mecânico do disco intervertebral recorrendo a sensores em fibra ótica. Na expetativa de efetuar o melhor enquadramento do tema foi efetuada uma revisão exaustiva das várias configurações de sensores em fibra ótica que têm vindo a ser utilizadas em aplicações biomédicas e biomecânicas, nomeadamente para medição de temperatura, deformação, força e pressão. Nesse âmbito, procurou-se destacar as potencialidades dos sensores em fibra ótica e apresentá-los como uma tecnologia alternativa ou até de substituição das tecnologias associadas a sensores convencionais. Tendo em vista a aplicação de sensores em fibra ótica no estudo do comportamento do disco intervertebral efetuou-se também uma revisão exaustiva da coluna vertebral e, particularmente, do conceito de unidade funcional. A par de uma descrição anatómica e funcional centrada no disco intervertebral, vértebras adjacentes e ligamentos espinais foram ainda destacadas as suas propriedades mecânicas e descritos os procedimentos mais usuais no estudo dessas propriedades. A componente experimental do presente trabalho descreve um conjunto de experiências efetuadas com unidades funcionais cadavéricas utilizando sensores convencionais e sensores em fibra ótica com vista à medição da deformação do disco intervertebral sob cargas compressivas uniaxiais. Inclui ainda a medição in vivo da pressão intradiscal num disco lombar de uma ovelha sob efeito de anestesia. Para esse efeito utilizou-se um sensor comercial em fibra ótica e desenvolveu-se a respetiva unidade de interrogação. Finalmente apresenta-se os resultados da investigação em curso que tem como objetivo propor e desenvolver protótipos de sensores em fibra ótica para aplicações biomédicas e biomecânicas. Nesse sentido, são apresentadas duas soluções de sensores interferométricos para medição da pressão em fluídos corporais.The present work aimed to study the mechanical behavior of the intervertebral disc using fiber optic sensors. To address the theme an exhaustive review of the various configurations of fiber optic sensors that have been used in biomechanical and biomedical applications, in particular for measuring temperature, strain, force and pressure, was conducted. In this context, an effort was made to highlight the advantages of fiber optic sensors and present them as an alternative or even a substitution technology to conventional sensors. In view of the application of fiber optic sensors to study intervertebral disc behavior an exhaustive review of the spine and, particularly, of the spinal motion segment was made. Along with an anatomical and functional description of the intervertebral disc, the adjacent vertebrae and spinal ligaments, their mechanical properties were also highlighted as well as the most common procedures and guidelines followed in the study of these properties. The experimental section of the present work describes a set of tests performed with cadaveric spinal motion segments using conventional and fiber optic sensors to assess strain of the intervertebral disc under uniaxial compressive loads. This section also includes an experience reporting in vivo pressures measured in the lumbar disc of a sheep under general anesthesia. In this case, a commercial fiber optic sensor and a purpose-built interrogation unit were used. Finally, the results of ongoing research aiming to develop fiber optic sensors prototypes for biomedical and biomechanical applications are presented. Thus, the proof of concept of two possible interferometric configurations intended for pressure measurement in body fluids was presented