Teleoperation of MRI-Compatible Robots with Hybrid Actuation and Haptic Feedback

Image guided surgery (IGS), which has been developing fast recently, benefits significantly from the superior accuracy of robots and magnetic resonance imaging (MRI) which is a great soft tissue imaging modality. Teleoperation is especially desired in the MRI because of the highly constrained space inside the closed-bore MRI and the lack of haptic feedback with the fully autonomous robotic systems. It also very well maintains the human in the loop that significantly enhances safety. This dissertation describes the development of teleoperation approaches and implementation on an example system for MRI with details of different key components. The dissertation firstly describes the general teleoperation architecture with modular software and hardware components. The MRI-compatible robot controller, driving technology as well as the robot navigation and control software are introduced. As a crucial step to determine the robot location inside the MRI, two methods of registration and tracking are discussed. The first method utilizes the existing Z shaped fiducial frame design but with a newly developed multi-image registration method which has higher accuracy with a smaller fiducial frame. The second method is a new fiducial design with a cylindrical shaped frame which is especially suitable for registration and tracking for needles. Alongside, a single-image based algorithm is developed to not only reach higher accuracy but also run faster. In addition, performance enhanced fiducial frame is also studied by integrating self-resonant coils. A surgical master-slave teleoperation system for the application of percutaneous interventional procedures under continuous MRI guidance is presented. The slave robot is a piezoelectric-actuated needle insertion robot with fiber optic force sensor integrated. The master robot is a pneumatic-driven haptic device which not only controls the position of the slave robot, but also renders the force associated with needle placement interventions to the surgeon. Both of master and slave robots mechanical design, kinematics, force sensing and feedback technologies are discussed. Force and position tracking results of the master-slave robot are demonstrated to validate the tracking performance of the integrated system. MRI compatibility is evaluated extensively. Teleoperated needle steering is also demonstrated under live MR imaging. A control system of a clinical grade MRI-compatible parallel 4-DOF surgical manipulator for minimally invasive in-bore prostate percutaneous interventions through the patient’s perineum is discussed in the end. The proposed manipulator takes advantage of four sliders actuated by piezoelectric motors and incremental rotary encoders, which are compatible with the MRI environment. Two generations of optical limit switches are designed to provide better safety features for real clinical use. The performance of both generations of the limit switch is tested. MRI guided accuracy and MRI-compatibility of whole robotic system is also evaluated. Two clinical prostate biopsy cases have been conducted with this assistive robot

Endoscopic tissue liquidisation of the prostate, bladder and kidney

Endoscopic techniques have revolutionised the practice of all specialities of surgery. Endoscopic access has been either via a natural route, such as the urethra, or percutaneously, as in percutaneous intrarenal stone surgery. Potential endoscopic procedures for bulk tissue removal have been limited by the need to reduce that tissue to a size smaller than the endoscopic channel used. An attempt has been made to create a device that will liquidise and aspirate tissue through an endoscope, This Instrument has been called the Endoscopic Liquidiser and Surgical Aspirator (ELSA). This report details the design and development of the ELSA which has led to its clinical application. The device is 5 mm in diameter and is used through a specially made endoscope of 8.5 mm outer diameter (approximately 27 French). It consists of a high speed rotating blade mounted in a housing that provides irrigation for efficient 1iquidisation and a channel for aspiration of the tissue. Laboratory evaluation was measured by the removal rates of different tissues. The optimum parameters of blade speed, irrigation flow and aspiration were established after a series of controlled experiments. Blade shape was also found to be important and a study of the material strengths of different tissues was required to establish that blade design should vary for each tissue used. Under optimum laboratory conditions fresh human prostate could be removed at 2.4 g/min and renal cortex at 14.6 g/min. The resultant aspirate contained particles ranging from 10 microns to 3 mm, but the majority were less than 200 microns. Flow cytometry was required as the only reasonable method of rapid pathological diagnosis. The action of the ELSA did not confer any Inherent haemostatic benefit and a diathermy plate was added to the tip of the instrument. The ELSA was successfully used to remove benign prostatic tissue from 7 patients with bladder outflow obstruction. However the procedures were slow and visualisation was poor once the liquidisation began. The mean operating time was 85 minutes (range 50 - 120). 1 patient suffered a fatal capsular perforation, but otherwise morbidity v/as not dissimilar from a control group undergoing a standard transurethral diathermy resection. 6'7 patients regained an improved stream with good control. The ELSA was used in the same transurethral method for the removal of superficial bladder tumours in 10 patients. The same problem of impaired vision was found, but the removal was very rapid as one would expect with a soft non-fibro\is material. The postoperative morbidity was greater than in a control group using a diathermy resectoscope due to bladder perforation with the ELSA in 1 case. A percutaneous endoscopic nephrectomy has been achieved in 2 dogs. Each kidney was embolised with "Ethibloc" (a material that completely occupies all arterial capillary beds), An Intrarenal approach was compared with an extrarenal, retroperitoneal one; the latter using carbon dioxide insufflation. Both procedures were successful. Haeraostasis was not a problem. These may be suitable clinical techniques for the minimally invasive removal of infected kidneys prior to transplantation. The presence of stones would not be a problem because of the ability of the ELSA to fragment and aspirate stone particles as efficently as any ultrasound device. This was confirmed in a series of laboratory tests on various stone types and in 5 patients with urinary stones. An extension of the concept of minimally invasive bulk tissue aspiration is the integration of robotics into this form of surgery. The ELSA has been attached to an industrial robot. The mechanism of a transurethral prostatectomy has been studied in order to program the robot. A robotic prostatectomy in a simulation model has been performed. Each procedure can be preprogrammed according to the dimensions of the gland. The in vitro study confirmed that the robot was consistent and therefore safe; and rapid (mean removal time 5 rains) because visualisation was not required for orientation. In conclusion, the ELSA has proved to be ati efficient instrument for endoscopic tissue removal but its clinical superiority is only for less fibrous tissues and improved visualisation will be required. It still requires ancillary methods for haemostasis and the use of a capillary embolisation technique in the kidney may have applications elsewhere. The robotic study was not just an academic exercise. Robotics will be a feature of future surgery

Development of positioning devices for MRI-guided high intensity focused ultrasound (HIFU) for abdominal, thyroid and brain, tumours

High intensity focused ultrasound (HIFU) is a promising technology for a variety of therapeutic applications. This concept initiated in 1942 by Lynn Zwemer [1]. HIFU has long been known as a minimal invasive or non-invasive procedure that destroys tissue through ablation. However, it is only in recent years that clinical applications are becoming feasible, with the development of high power ultrasound transducers compatible with the MRI scanner which is used to monitor these non-invasive HIFU applications. New technologies, combined with more sophisticated treatment methods and monitoring methods allow non-invasive procedures in many areas such as the brain, eye, breast, kidney, liver, pancreas, thyroid, uterine fibroids and pancreas. Meanwhile, new investigations are underway for treading cardiac arithmia, strokes, palliative pain treatment of bone metastases and brain disorders such as Parkinson’s disease, essential tremor, and neuropathic pain. These optimistic investigations have encouraged physicians and provided them new valuable tools for medical research

The real-time molecular characterisation of human brain tumours during surgery using Rapid Evaporative Ionization Mass Spectrometry [REIMS] and Raman spectroscopy: a platform for precision medicine in neurosurgery

Aim: To investigate new methods for the chemical detection of tumour tissue during neurosurgery. Rationale: Surgeons operating on brain tumours currently lack the ability to directly and immediately assess the presence of tumour tissue to help guide resection. Through developing a first in human application of new technology we hope to demonstrate the proof of concept that chemical detection of tumour tissue is possible. It will be further demonstrated that information can be obtained to potentially aid treatment decisions. This new technology could, therefore, become a platform for more effective surgery and introducing precision medicine to Neurosurgery. Methods: Molecular analysis was performed using Raman spectroscopy and Rapid Evaporative Ionization Mass Spectrometry (REIMS). These systems were first developed for use in brain surgery. A single centre prospective observational study of both modalities was designed involving a total of 75 patients undergoing craniotomy and resection of a range of brain tumours. A neuronavigation system was used to register spectral readings in 3D space. Precise intraoperative readings from different tumour zones were taken and compared to matched core biopsy samples verified by routine histopathology. Results: Multivariate statistics including PCA/LDA analysis was used to analyse the spectra obtained and compare these to the histological data. The systems identified normal versus tumour tissue, tumour grade, tumour type, tumour density and tissue status of key markers of gliomagenesis. Conclusions: The work in this thesis provides proof of concept that useful real time intraoperative spectroscopy is possible. It can integrate well with the current operating room setup to provide key information which could potentially enhance surgical safety and effectiveness in increasing extent of resection. The ability to group tissue samples with respect to genomic data opens up the possibility of using this information during surgery to speed up treatment, escalate/deescalate surgery in specific phenotypic groups to introduce precision medicine to Neurosurgery.Open Acces

Investigating Ultrasound-Guided Autonomous Assistance during Robotic Minimally Invasive Surgery

Despite it being over twenty years since the first introduction of robotic surgical systems in common surgical practice, they are still far from widespread across all healthcare systems, surgical disciplines and procedures. At the same time, the systems that are used act as mere tele-manipulators with motion scaling and have yet to make use of the immense potential of their sensory data in providing autonomous assistance during surgery or perform tasks themselves in a semi-autonomous fashion. Equivalently, the potential of using intracorporeal imaging, particularly Ultrasound (US) during surgery for improved tumour localisation remains largely unused. Aside from the cost factors, this also has to do with the necessity of adequate training for scan interpretation and the difficulty of handling an US probe near the surgical sight. Additionally, the potential for automation that is being explored in extracorporeal US using serial manipulators does not yet translate into ultrasound-enabled autonomous assistance in a surgical robotic setting. Motivated by this research gap, this work explores means to enable autonomous intracorporeal ultrasound in a surgical robotic setting. Based around the the da Vinci Research Kit (dVRK), it first develops a surgical robotics platform that allows for precise evaluation of the robot’s performance using Infrared (IR) tracking technology. Based on this initial work, it then explores the possibility to provide autonomous ultrasound guidance during surgery. Therefore, it develops and assesses means to improve kinematic accuracy despite manipulator backlash as well as enabling adequate probe position with respect to the tissue surface and anatomy. Founded on the acquired anatomical information, this thesis explores the integration of a second robotic arm and its usage for autonomous assistance. Starting with an autonomously acquired tumor scan, the setup is extended and methods devised to enable the autonomous marking of margined tumor boundaries on the tissue surface both in a phantom as well as in an ex-vivo experiment on porcine liver. Moving towards increased autonomy, a novel minimally invasive High Intensity Focused Ultrasound (HIFUS) transducer is integrated into the robotic setup including a sensorised, water-filled membrane for sensing interaction forces with the tissue surface. For this purpose an extensive material characterisation is caried out, exploring different surface material pairings. Finally, the proposed system, including trajectory planning and a hybrid-force position control scheme are evaluated in a benchtop ultrasound phantom trial

Endoscopy

Endoscopy is a fast moving field, and new techniques are continuously emerging. In recent decades, endoscopy has evolved and branched out from a diagnostic modality to enhanced video and computer assisting imaging with impressive interventional capabilities. The modern endoscopy has seen advances not only in types of endoscopes available, but also in types of interventions amenable to the endoscopic approach. To date, there are a lot more developments that are being trialed. Modern endoscopic equipment provides physicians with the benefit of many technical advances. Endoscopy is an effective and safe procedure even in special populations including pediatric patients and renal transplant patients. It serves as the tool for diagnosis and therapeutic interventions of many organs including gastrointestinal tract, head and neck, urinary tract and others

New Insight into Cerebrovascular Diseases

“Brain circulation is a true road map that consists of large extended navigation territories and a number of unimagined and undiscovered routes.” Dr. Patricia Bozzetto Ambrosi This book combines an update on the review of cerebrovascular diseases in the form of textbook chapters, which has been carefully reviewed by Dr. Patricia Bozzetto Ambrosi, Drs. Rufai Ahmad and Auwal Abdullahi and Dr. Amit Agrawal, high-performance academic editors with extensive experience in neurodisciplines, including neurology, neurosurgery, neuroscience, and neuroradiology, covering the best standards of neurological practice involving basic and clinical aspects of cerebrovascular diseases. Each topic was carefully revised and prepared using smooth, structured vocabulary, plus superb graphics and scientific illustrations. In emphasizing the most common aspects of cerebrovascular diseases: stroke burden, pathophysiology, hemodynamics, diagnosis, management, repair, and healing, the book is comprehensive but concise and should become the standard reference guide for this neurological approach

Plessner's Philosophical Anthropology. Perspectives and Prospects

Helmuth Plessner (1892-1985) was one of the founders of philosophical anthropology, and his book The Stages of the Organic and Man, first published in 1928, has inspired generations of philosophers, biologists, social scientists, and humanities scholars. This volume offers the first substantial introduction to Plessner’s philosophical anthropology in English, not only setting it in context with such familiar figures as Bergson, Cassirer, and Merleau-Ponty, but also showing Plessner’s relevance to contemporary discussions in a wide variety of fields in the humanities and sciences