Intuitive and Efficient Control of Real-Time MRI Scan Plane Using a Six-Degree-of-Freedom Hardware Plane Navigator

Abstract

Abstract. For applications of real-time MRI, it is important but difficult to efficiently prescribe the next scan plane and obtain visual feedback on the prescription. This work addresses these issues with a 6-degreeof-freedom Plane Navigator. The Plane Navigator is a mechanical arm with integrated input and output functionality while being statically balanced. In the input mode, by holding and moving the surface normal of the physical representation of the scan plane, the operator can intuitively place the scan plane at a position with any orientation within a few milliseconds. In the output mode, the Plane Navigator automatically places the physical representation of the scan plane to reflect its position and orientation (pose)[PR1] relative to a patient domain with a maximum delay of half a second. Application examples in MRI cardiac imaging are also described.

A Mechatronic System for Interactive Scan Plan Prescription during Real-Time Cardiac Magnetic Resonance Imaging

“…A custom designed 3D input device is used to allow the user to interactively and intuitively manipulate the scan plane to direct the real-time imaging capability to a target position based on the visual feedback provided on the MRI console in the form of real-time MRI images [8,10]. The armlike mechanical armature is named as the Plane Navigator or the PN tool for short.…”

“…Figure 2 below shows a version of PN tool containing of 7 sequential rotational joints. A 6-joint version of the PN tool was invited to exhibit in the InfoRad Theater at the 90th scientific assembly and annual meeting of RSNA in 2004 [10].…”

“…Each version of the PN tool has two functional modes [8,11]. In input mode it can simultaneously provide 6-DOF inputs to define the location and orientation of a virtual plane (i.e., scan plane) in 3D space (e.g., the MRI scan plane).…”

“…In order to expand the application of a conventional MRI scanner to cover the visualization of structures and dynamic changes of a beating heart, especially for a patient or for a fetus who can't hold their breath long, or to visualize and track surgical tools during a minimum invasive surgery, etc, an intuitive user interface must be developed to enable a conventional MRI scanner to do fast interactive real-time imaging. The lack of a suitable tool integrated with an intuitive user-interface for interactive and intuitive manipulation of the scan plane is one of the major obstacles that prevent real-time MRI from expanding its clinical application [4][5][6][7][8]. Therefore a project is designated to develop individual components required by a real-time interactive MRI and accordingly to do system integration [8][9].…”

“…The lack of a suitable tool integrated with an intuitive user-interface for interactive and intuitive manipulation of the scan plane is one of the major obstacles that prevent real-time MRI from expanding its clinical application [4][5][6][7][8]. Therefore a project is designated to develop individual components required by a real-time interactive MRI and accordingly to do system integration [8][9]. The resulting system can be readily applicable for MRI diagnostic imaging as well as for MRI guided therapeutic procedures.…”