μRIGS – Ultra-light Micropositioning Robotics for Universal MRI Guided Interventions

Abstract Performing minimal invasive interventions under real-time image guidance proves problematic in a closed-bore magnetic resonance imaging scanner. To enable better usability in MRI guided interventions, robotic systems could be used for additional assistance. However, the integration of such devices into the clinical workflow relates to many technical challenges in order to increase precision of the procedure while ensuring the overall safety. In this work, an MR compatible, compact, ultra-light and remotely controllable micropositioning system called μRIGS is presented. The instrument positioning unit can be operated in a 5-DoF range within a working volume of 2100 cm3with an instrument feed of 120 mm. The kinematics are actuated with a combination of non-metallic Bowden cables and electric stepper motors from a safe distance inside the scanner room, while their control is initiated from the control room via a custom-fitted GUI. Thereby, the precision of the positioning reproducibility of the respective DoF can be achieved with a mean deviation of 0.12 °. Furthermore, a feed force of 14 N can be provided to puncture various soft tissue.

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Enhanced MRI-guided radiotherapy with gadolinium-based nanoparticles: preclinical evaluation with an MRI-linac

Cancer Nanotechnology ◽

10.1186/s12645-020-00065-5 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

H. L. Byrne ◽

G. Le Duc ◽

F. Lux ◽

O. Tillement ◽

N. M. Holmes ◽

...

Keyword(s):

Mr Imaging ◽

Radiation Treatment ◽

Cine Mri ◽

Clinical Workflow ◽

Nanoparticle Uptake ◽

Image Guided Radiotherapy ◽

Preclinical Evaluation ◽

Cine Mr ◽

Mri Guided ◽

Radiotherapy Treatment

Abstract Background The AGuIX® (NH TherAguix) nanoparticle has been developed to enhance radiotherapy treatment and provide strong MR contrast. These two properties have previously been investigated separately and progressed to clinical trial following a clinical workflow of separate MR imaging followed some time later by radiotherapy treatment. The recent development of MRI-linacs (combined Magnetic Resonance Imaging–linear accelerator systems enabling MRI-guided radiotherapy) opens up a new workflow where MR confirmation of nanoparticle uptake can be carried out at the time of treatment. A preclinical study was carried out to assess the suitability of a gadolinium-containing nanoparticle AGuIX® (NH TherAguix) for nano-enhanced image-guided radiotherapy on an MRI-linac. Methods Treatments were carried out on F344 Fischer rats bearing a 9L glioma brain tumour. Animals received either: (A) no treatment; (B) injection of nanoparticles followed by MRI; (C) radiotherapy with MRI; or (D) injection of nanoparticles followed by radiotherapy with MRI. Pre-clinical irradiations were carried out on the 1.0 T, 6 MV in-line Australian MRI-linac. Imaging used a custom head coil specially designed to minimise interference from the radiotherapy beam. Anaesthetised rats were not restrained during treatment but were monitored with a cine-MRI sequence. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) analysis was used to quantify residual gadolinium in the brain in normal and tumour tissue. Results A preclinical evaluation of nano-enhanced radiation treatment has been carried out on a 1.0 T MRI-linac, establishing a workflow on these novel systems. Extension of life when combining radiotherapy with nanoparticles was not statistically different from that for rats receiving radiotherapy only. However, there was no detrimental effect for animals receiving nanoparticles and radiation treatment in the magnetic field compared with control branches. Cine-MR imaging was sufficient to carry out monitoring of anaesthetised animals during treatment. AGuIX nanoparticles demonstrated good positive contrast on the MRI-linac system allowing confirmation of tumour extent and nanoparticle uptake at the time of treatment. Conclusions Novel nano-enhanced radiotherapy with gadolinium-containing nanoparticles is ideally suited for implementation on an MRI-linac, allowing a workflow with time-of-treatment imaging. Live irradiations using this treatment workflow, carried out for the first time at the Australian MRI-linac, confirm the safety and feasibility of performing MRI-guided radiotherapy with AGuIX® nanoparticles. Follow-up studies are needed to demonstrate on an MRI-linac the radiation enhancement effects previously shown with conventional radiotherapy.

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Robot for MRI-Guided Prostate Cancer Focal Laser Ablation

2017 Design of Medical Devices Conference ◽

10.1115/dmd2017-3511 ◽

2017 ◽

Author(s):

Zion Tsz Ho Tse ◽

Sheng Xu ◽

Alexander Squires ◽

Yue Chen ◽

Reza Seifabadi ◽

...

Keyword(s):

Prostate Cancer ◽

Laser Ablation ◽

Degrees Of Freedom ◽

Target Position ◽

The United States ◽

Clinical Workflow ◽

Passive Rotation ◽

Mri Guided ◽

Compact Design ◽

Mri Conditional

Prostate cancer is the most common cancer among males, leading to approximately 27,000 deaths in the United States [1]. Focal laser ablation (FLA) has been shown to be a promising approach for prostate cancer treatment with the advantage of efficiently ablating the cancer cells while inflicting less damage on the surrounding tissues. In current FLA procedures, a rigid template — with holes spacing of 5mm — guides the FLA catheter to the target position. Drawbacks of the conventional approach for catheter targeting are 1) limited degrees of freedom (DoF) and 2) a low insertion resolution. In addition, the targeting capability of the rigid template is compromised when the pubic arch or nerve bundles intersect the catheter trajectory. We hypothesized that a compact design of an MRI-conditional robot with two active planar DoFs, one passive rotation DoF, and remote catheter insertion capacities could enhance the clinical workflow required for MRI-guided FLA prostate procedures.

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Body-Mounted Robotic System for MRI-Guided Shoulder Arthrography: Cadaver and Clinical Workflow Studies

Frontiers in Robotics and AI ◽

10.3389/frobt.2021.667121 ◽

2021 ◽

Vol 8 ◽

Author(s):

Niravkumar Patel ◽

Jiawen Yan ◽

Gang Li ◽

Reza Monfaredi ◽

Lukasz Priba ◽

...

Keyword(s):

Shoulder Joint ◽

Joint Space ◽

Needle Insertion ◽

Cadaver Study ◽

Single Step ◽

Robotic System ◽

Clinical Workflow ◽

Shoulder Arthrography ◽

Mr Conditional ◽

Mri Guided

This paper presents an intraoperative MRI-guided, patient-mounted robotic system for shoulder arthrography procedures in pediatric patients. The robot is designed to be compact and lightweight and is constructed with nonmagnetic materials for MRI safety. Our goal is to transform the current two-step arthrography procedure (CT/x-ray-guided needle insertion followed by diagnostic MRI) into a streamlined single-step ionizing radiation-free procedure under MRI guidance. The MR-conditional robot was evaluated in a Thiel embalmed cadaver study and healthy volunteer studies. The robot was attached to the shoulder using straps and ten locations in the shoulder joint space were selected as targets. For the first target, contrast agent (saline) was injected to complete the clinical workflow. After each targeting attempt, a confirmation scan was acquired to analyze the needle placement accuracy. During the volunteer studies, a more comfortable and ergonomic shoulder brace was used, and the complete clinical workflow was followed to measure the total procedure time. In the cadaver study, the needle was successfully placed in the shoulder joint space in all the targeting attempts with translational and rotational accuracy of 2.07 ± 1.22 mm and 1.46 ± 1.06 degrees, respectively. The total time for the entire procedure was 94 min and the average time for each targeting attempt was 20 min in the cadaver study, while the average time for the entire workflow for the volunteer studies was 36 min. No image quality degradation due to the presence of the robot was detected. This Thiel-embalmed cadaver study along with the clinical workflow studies on human volunteers demonstrated the feasibility of using an MR-conditional, patient-mounted robotic system for MRI-guided shoulder arthrography procedure. Future work will be focused on moving the technology to clinical practice.

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Structure Design and Kinematics Analysis of MRI-Guided Intervention Robot

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.121-126.2253 ◽

2011 ◽

Vol 121-126 ◽

pp. 2253-2257

Author(s):

Yong De Zhang ◽

Hai Yan Du ◽

Li Wei Geng ◽

Yu Qin Li ◽

Hong Xia Zhang ◽

...

Keyword(s):

Structure Design ◽

Robot Design ◽

Kinematics Analysis ◽

Surgical Biopsy ◽

Image Guided ◽

Workspace Analysis ◽

Real Time Image ◽

Mri Environment ◽

Mri Guided ◽

Time Image

MRI-compatible surgical robot technology is one of the most effective ways to improve the real-time image-guided surgical biopsy. In MRI environment, the robot design is facing the problems of high magnetic field and limited workspace. A pneumatic-driven MRI-guided intervention robot was designed for chest and abdomen surgical biopsy. Based on compatibility and workspace analysis, the specific structure design of the robot was carried out. Then robot coordinate system was established using D-H method and the kinematics analysis was conducted.

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System Integration and Preliminary Clinical Evaluation of a Robotic System for MRI-Guided Transperineal Prostate Biopsy

Journal of Medical Robotics Research ◽

10.1142/s2424905x19500016 ◽

2019 ◽

Vol 04 (02) ◽

pp. 1950001 ◽

Cited By ~ 8

Author(s):

Niravkumar A. Patel ◽

Gang Li ◽

Weijian Shang ◽

Marek Wartenberg ◽

Tamas Heffter ◽

...

Keyword(s):

Clinical Study ◽

Prostate Biopsy ◽

Modular Design ◽

Surgical Navigation ◽

Robotic System ◽

Clinical Workflow ◽

Preclinical Evaluation ◽

Transperineal Prostate Biopsy ◽

Patient Consent ◽

Mri Guided

This paper presents the development, preclinical evaluation, and preliminary clinical study of a robotic system for targeted transperineal prostate biopsy under direct interventional magnetic resonance imaging (MRI) guidance. The clinically integrated robotic system is developed based on a modular design approach, comprised of surgical navigation application, robot control software, MRI robot controller hardware, and robotic needle placement manipulator. The system provides enabling technologies for MRI-guided procedures. It can be easily transported and setup for supporting the clinical workflow of interventional procedures, and the system is readily extensible and reconfigurable to other clinical applications. Preclinical evaluation of the system is performed with phantom studies in a 3 Tesla MRI scanner, rehearsing the proposed clinical workflow, and demonstrating an in-plane targeting error of 1.5[Formula: see text]mm. The robotic system has been approved by the institutional review board (IRB) for clinical trials. A preliminary clinical study is conducted with the patient consent, demonstrating the targeting errors at two biopsy target sites to be 4.0[Formula: see text]mm and 3.7[Formula: see text]mm, which is sufficient to target a clinically significant tumor foci. First-in-human trials to evaluate the system’s effectiveness and accuracy for MR image-guided prostate biopsy are underway.

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Design of a Spectroscopic Low-Energy Emission Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180549 ◽

1990 ◽

Vol 48 (1) ◽

pp. 358-359

Author(s):

Lee H. Veneklasen

Keyword(s):

Parallel Imaging ◽

Objective Lens ◽

Energy Window ◽

Flat Surfaces ◽

Beam Voltage ◽

New Instrument ◽

Real Time Image ◽

Image Planes ◽

Backscatter Diffraction ◽

Time Image

This paper discusses some of the unique aspects of a spectroscopic emission microscope now being tested in Clausthal. The instrument is designed for the direct parallel imaging of both elastic and inelastic electrons from flat surfaces. Elastic contrast modes of the familiar LEEM include large and small angle LEED, mirror microscopy, backscatter diffraction contrast (for imaging of surface structure), and phase contrast (for imaging of step dynamics)(1). Inelastic modes include topology sensitive secondary, and work function sensitive photoemission. Most important, the new instrument will also allow analytical imaging using characteristic Auger or soft X-ray emissions. The basic instrument has been described by Bauer and Telieps (2). This configuration has been redesigned to include an airlock, and a LaB6 gun, triple condensor lens, magnetic objective lens, a double focussing separator field, an imaging energy analyzer, and a real time image processor.Fig. 1 shows the new configuration. The basic beam voltage supply Vo = 20 KV, upon which separate supplies for the gun Vg, specimen Vs, lens electrode Vf, and analyzer bias Vb float. The incident energy at the sample can be varied from Vs = 0-1 KV for elastic imaging, or from Vg + Vs = (3 + Vs) KV for inelastic imaging. The image energy window Vs±V/2 may be varied without readjusting either the illumation, or imaging/analyzer optics. The diagram shows conjugate diffraction and image planes. The apertures defining incoming Humiliation and outgoing image angles are placed below the separator magnet to allow for their independent optimization. The instrument can illuminate and image 0.5-100 μm fields at 0-1 keV emission energies with an energy window down to 0.2 eV.

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