Sunram 7: An MR Safe Robotic System for Breast Biopsy

In breast cancer patients, some nodules are only visible on MRI, thus, requiring MRI-guidance to perform the biopsy. MRI interventions are cumbersome due to the magnetic field and the constrained working space. An MR safe robotic system actuated by pneumatic stepper motors may enable these procedures, improving both accuracy and image-guided navigation. A compact multipurpose pneumatic stepper motor has been designed with outer dimensions $(45 \times 40\times 15)\mathbf{mm}^{\mathbf{3}}$. This is configurable as a linear, rotational or curved stepper motor with a customizable step size and radius of curvature. Five copies of these motors actuate the Sunram 7 biopsy robot, of which the moving part (without protruding racks and tubes) measures $(130 \times 65\times 55)\mathbf{mm}^{\mathbf{3}}$. After manually choosing the target location and angle of approach, the needle is robotically inserted into the breast and the integrated pneumatic biopsy gun is fired to sample tissue from the lesion. The maximum torque of the presented motor is 0.61 N m at 6 bar which can be achieved using 13-teeth polycarbonate gears. Using 17-teeth gears for higher accuracy and a more convenient working pressure of 2 bar the maximum torque is 0.28 N m. The accuracy in free air of the Sunram 7 robot is 1.69mm and 1.72mm in X and Z-direction respectively, with a resulting 2-D error of 2.54 mm. The workspace volume is 4.1 L. When targeting 10 mm-sized lesions in phantoms under MRI guidance, Sunram 7 achieved a success rate of 68%. The minimum interval between two successive biopsies was 5:47 minutes. The presented multipurpose stepper motor has distinct advantages over previous designs in terms of robustness, customizability, printability and ease of integration in MR safe robotics. The Sunram 7 is able to perform accurate MRI-guided biopsies in a large workspace volume while reducing the intervention time when compared to the gold standard (i.e., MRI-guided free-hand biopsy)

Needle and Biopsy Robots: a Review

Purpose of the review Robotics is a rapidly advancing field, and its introduction in healthcare can have a multitude of benefits for clinical practice. Especially, applications depending on the radiologist\u2019s accuracy and precision, such as percutaneous interventions, may profit. This paper provides an overview of recent robot-assisted percutaneous solutions. Recent findings Percutaneous interventions are relatively simple and the quality of the procedure increases a lot by introducing robotics due to the improved accuracy and precision. The success of the procedure is heavily dependent on the ability to merge pre- and intraoperative images, as an accurate estimation of the current target location allows to exploit the robot\u2019s capabilities. Summary Despite much research, the application of robotics in some branches of healthcare is not commonplace yet. Recent advances in percutaneous robotic solutions and imaging are highlighted, as they will pave the way to more widespread implementation of robotics in clinical practic

MR conditional prostate intervention systems and actuations review

Magnetic resonance imaging (MRI) has the ability to provide high-resolution images of soft tissues without the use of radiation. So much research has been focused on the development of actuators and robotic devices that can be used in the MRI environment so “real-time” images can be obtained during surgeries. With real-time guidance from MRI, robots can perform surgical procedures with high accuracy and through less invasive routes. This technique can also significantly reduce the operation time and simplify pre-surgical procedures. Therefore, research on robot-assisted MRI-guided prostate intervention has attracted a great deal of interest, and several successful clinical trials have been published in recent years, pointing to the great potential of this technology. However, the development of MRI-guided robots is still in the primary stage, and collaboration between researchers and commercial suppliers is still needed to improve such robot systems. This review presents an overview of MRI-guided prostate intervention devices and actuators. Additionally, the expected technical challenges and future advances in this field are discussed

Stormram 3: A Magnetic Resonance Imaging-Compatible Robotic System for Breast Biopsy

Stormram 3 is an MRI-compatible robotic system that can perform MR guided breast biopsies of suspicious lesions. The base of the robot measures 160x180x90 mm and it is actuated by five custom pneumatic linear stepper motors, driven by a valve manifold outside the Faraday cage of the MRI scanner. All parts can be rapidly prototyped with 3-D printing or laser-cutting, making the design suitable for other applications such as actuation in hazardous environments. Based on the choice of materials, the robot (with the exception of the needle) is inherently MR-safe. Measurements show that the maximum force of the T-49 actuator is 70 N, at a pressure of 0.3 MPa. The Stormram 3 has an optimized repeatability which is lower than 0.5 mm, and can achieve a positional accuracy in the order of 2 mm