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Heart disease is highly prevalent in developed countries, causing 1 in 4 deaths. In this work we propose a method for a fully automated 4D reconstruction of the left ventricle of the heart. This can provide accurate information regarding the heart wall motion and in particular the hemodynamics of the ventricles. Such metrics are crucial for detecting heart function anomalies that can be an indication of heart disease. Our approach is fast, modular and extensible. In our testing, we found that generating the 4D reconstruction from a set of 250 MRI images takes less than a minute. The amount of time saved as a result of our work could greatly benefit physicians and cardiologist as they diagnose and treat patients.

This work presents a prototype holographic interface (HI) for the 3D visualization of MRI data for the purpose of planning neurosurgical procedures. The presented HI (i) immerses the operator to a mixed reality (MiR) scene, which includes MRI data and virtual renderings, (ii) facilitates interactive manipulation of the objects of the MiR scene for planning and (iii) is the front-end of a pipeline that links the operator to the MRI scanner for on-the-fly control of the scanner. Preliminary qualitative evaluation revealed that holographic visualization of high-resolution 3D MRI data offers an intuitive and interactive perspective of the complex brain vasculature and anatomical structures. These early work further suggests that immersive experience may be an unparalleled tool in better planning neurosurgical procedures. Further development is required to speed up the pipeline from the MRI scanner to the HI and incorporating means of manipulations other than gestures.

Image-guided and robot-assisted surgical procedures are rapidly evolving due to their potential to improve patient management and cost effectiveness. Magnetic Resonance Imaging (MRI) is used for pre-operative planning and is also investigated for real-time intra-operative guidance. A new type of technology is emerging that uses the magnetic field gradients of the MR scanner to maneuver ferromagnetic agents for local delivery of therapeutics. With this approach, MRI is both a sensor and forms a closed-loop controlled entity that behaves as a robot (we refer to them as MRbots). The objective of this paper is to introduce a computational framework for preoperative planning using MRI and modeling of MRbot maneuvering inside tortuous blood vessels. This platform generates a virtual corridor that represents a safety zone inside the vessel that is then used to access the safety of the MRbot maneuvering. In addition, to improve safety we introduce a control that sets speed based on the local curvature of the vessel. The functionality of the framework was then tested on a realistic operational scenario of accessing a neurological lesion, a meningioma. This virtual case study demonstrated the functionality and potential of MRbots as well as revealed two primary challenges: real-time MRI (during propulsion) and the need of very strong gradients for maneuvering small MRbots inside narrow cerebral vessels. Our ongoing research focuses on further developing the computational core, MR tracking methods, and on-line interfacing to the MR scanner.

The development and initial testing of a prototype concentric tube robot suitable for surgical applications is presented. The system is endowed with 3 degrees-of-freedom and consists of a three concentric tubes assembly and an actuation module. Design issues are discussed in a general context of concentric tube robots in view of their potential applications in surgery. Among the distinct features of the system is that the actuation module provides a mechanical decoupling between the available motions that effectively facilitates control of the device. Such robotic systems are considered particularly suitable for MR- guided interventions and compatibility issues with the specific imaging modality are discussed. Initial experimental testing of the device is presented which involved tip targeting and steering trials using direct visual feedback for guidance.

A novel MR-compatible manually-actuated robotic manipulation device has been developed. It is a general-purpose system that provides access to the patient inside a closed-cylindrical MRI scanner. It allows the performance of various minimally-invasive interventions, such as biopsies and local drug deliveries, using real-time images for guidance and monitoring. The design of the system is described and the prototype constructed is presented together with initial MRI phantom testing on needle targeting. The characteristics and potential of manual actuation in MR-compatible robotic systems are examined.