Dynamic contrast enhanced magnetic resonance imaging (DCE MRI) in combination with ultrasound and/or X-ray imaging offers an excellent roadmap for intraoperative surgical guidance for complete excision of the true extent of disease in early stage breast cancer. However, incorporation of image-guidance in the operating room is challenging due to patient positioning, precise targeting under tissue deformation, instrument incompatibility and limited maneuverability, and complex human-technology interface. In this paper, we outline a novel strategy and preliminary simulation data on a proposed robot-assisted lumpectomy technique in the prone position using DCE MRI for real-time guidance. Extension to CT guidance for X-ray enhancing lesions would require minimal additional specifications. For ultrasound enhancing lesions, a method to ensure co-registration of the target with MRI is presented.

Inspired by the movement of comet under gravitational interaction with planets and stars, we propose a novel wavelet-gravitation network (WGN) for endoscope optical tracking. We substitute the world gravitation law with interaction described by radial wavelet function. The WGN is trained based on the energy conservation law. The prediction of target image position is made with movement described by the second Newton's law. The WGN is incorporated with Kalman filtering framework. Our experiments show that WGN performs especially well for nonlinear movement tracking. As the movement of surgical tools is hand-driven, it is mostly nonlinear and affected by both tangential and normal accelerations. Our proposed methodology has been successfully applied to endoscope tracking for image guided surgery

In this paper we present a semi-automated device designed and developed to deliver radio-active seeds for treating prostate cancer. In the brachytherapy procedure a slander needle is inserted through the perineum and passed through different types of tissues. Thus, the needle experiences significant amount of force which may cause it to buckle and bend. In our design, we have considered the buckling force and insertion force on needle by collecting invivo data from real patient and performing in-vitro experiments. Techniques to reduce force and organ/tissue deformation have been implemented into this new design. To track the axial force on the needle for detecting pubic arch interference and to improve robotic control, we have incorporated three force sensors. Rigidity and factor of safety of the device has been analyzed using finite element method which was very useful for iterative design process.

We present a prototype of a robotic system for accurate and consistent insertion of a percutaneous biopsy needle into the prostate. The robot manipulates a transrectal ultrasound (TRUS) probe to collect a series of 2 dimensional (2D) images of the prostate, which are later used to create a 3D computer model of the organ. The urologist defines the needle’s entry point at the perineal wall and the biopsy points within the 3D model following a biopsy protocol or otherwise. The robotic system then calculates the required trajectory of the needle. The path of the needle going into the prostate can also be simulated with the 3D model before the actual insertion. Being satisfied with the predicted outcome, the urologist configures the robot accordingly and manually pushes the mechanically guided needle into the patient to take the biopsy. Cadaveric and human trials have validated the robot’s needle placement error to be less than 2.5mm. Our future work includes the integration of a cancer predictive modality into the system to increase the cancer detection rate. The robotic system could also be modified to accurately place foreign bodies into the prostate, which could improve therapeutic procedures such as Brachytherapy.

Prostate boundary detection from ultrasound images plays a key role in prostate disease diagnoses and treatments. Due to the poor quality of ultrasound images, however, this still remains as a difficult task. Currently, boundary detection are performed manually, which is arduous and heavily user dependent. This paper presents a new approach derived from level set method to semiautomatically detect the prostate surface from 3D transrectal ultrasound images. In this method, a few initial bubbles are simply specified by the user from five particular slices based on the prostate shape. When bubbles evolve, they expand, shrink merge and split, and finally produce the desired prostate surface. To remedy the "boundary leaking" problem caused by gaps or weak boundaries, both region information and statistical intensity distribution are incorporated into the model. We applied the proposed method to eight 3D TRUS images and the results have shown its effectiveness.

Mixing 3D computer-generated images with real-scene images seamlessly in augmented reality has many desirable and wide areas of applications such as entertainment, cinematography, design visualization and medical trainings. The challenging task is to make virtual objects blend harmoniously into the real scene and appear as if they are like real. Apart from constructing detailed geometric 3D model representation and obtaining accurate surface properties for virtual objects, adopting real scene lighting information to render virtual objects is another important factor to achieve photorealistic rendering. Such a factor not only improves visual complexity of virtual objects, but also determines the consistency of illumination between the virtual objects and the surrounding real objects in the scene. Conventional rendering techniques such as ray tracing, and radiosity require intensive computation and data preparation to solve the lighting transport equation. Hence, they are less practical for rendering virtual objects in augmented reality, which demands a real-time performance. This work explores an image-based and hardware-based approach to improve photorealism for rendering synthetic objects in augmented reality. It uses a recent technique of image-based lighting, environment illumination maps, and a simple yet practical multi-pass rendering framework for augmented reality.

Prostate cancer accounts for 29% of all cancers diagnosed in males in the United States. Present therapeutic procedures for prostate cancer are either invasive or minimally invasive. However, recent advances in technology (e.g. High Intensity Focused Ultrasound (HIFU)) allow the possibility of also non-invasive therapeutic procedures. This paper describes localizing the position of the prostate using an ultrasound probe. With this information, the robot can accurately manipulate a non-invasive therapeutic tool, such as HIFU, to an area of interest in the prostate via the transperineal route.

Prostate cancer accounts for 29% of all cancers diagnosed in males in the United States. Resent therapeutic procedures for prostate cancer are either invasive or minimally invasive. However, recent advances in technology (e.g. High intensity Focused Ultrasound (HIFU)) allow the possibility of also non-invasive therapeutic procedures. This paper describes localizing the position of the prostate using an ultrasound probe. With this jnformation, the robot can accurately manipulate a non-invasive therapeutic tool, such as HlFU, to an area of interest in the prostate via the transperineal route.

A flexible multigradient active contour model is proposed in this paper for solving the "initial" position problem of active contour for implementing multi-layer boundary detection from anal ultrasound image. The core work is the application of multigradient field concepts as image forces in different phase of boundary finding. A preliminary test and assessment have been done on synthetic image, simulated ultrasound image and clinical image.

A parallel manipulator can be used for medical operations for its high stiffness and motion accuracy. However, the small and oddly distributed workspace of the general manipulator limits its applications. In this paper, a special manipulator which has a redundant degree of freedom (the 7-DOF) is introduced to improve the workspace. The workspace of the manipulator was analyzed with respect to the selected orientations. Two configurations of the 7-DOF were considered. The preliminary result of the analysis shows that the workspace of the manipulator can be effectively improved with the redundant degree of freedom.