Marco Mura

A New Concept for Magnetic Capsule Colonoscopy Based on an Electromagnetic System

Traditional endoscopy based on flexible endoscopes is reliable and effective, but poorly tolerated by patients; it also requires extended training by physicians. In order to reduce the invasiveness of these procedures, wireless passive capsule endoscopy has been proposed and clinically used during the past decade. A capsule endoscope with an active locomotion mechanism is desirable for carrying out controllable interactive procedures that are normally not possible using passive devices. Due to many difficulties in embedding actuators in swallowable devices, many researchers and companies have adopted an external magnetic field actuation solution. Magnetic resonance modified systems or permanent magnets are used to manoeuvre capsules remotely; however, both these cases present some limitations: magnetic resonance systems are bulky and expensive and permanent magnets are intrinsically unstable to control, and it is impossible to switch them off. Within this framework, the authors present the design and assessment of a magnetic system for endoscopic capsules based on an electromagnetic approach. In particular, the use of a single electromagnet was proposed and investigated: magnetic attraction, locomotion forces and magnetic torques were modelled for guaranteeing the reliable navigation of the capsule and based on these specifications, an electromagnet was designed, developed and experimentally evaluated. The results demonstrated the feasibility of the proposed approach for active locomotion capsule endoscopy.

Electromagnetic Control System for Capsule Navigation: Novel Concept for Magnetic Capsule Maneuvering and Preliminary Study.

The gastrointestinal tract is home of some of the most deadly human diseases. The main problems are related to the difficulty of accessing it for diagnosis or intervention and concomitant patient discomfort. The flexible endoscopy technique has established itself in medical practice due to its high diagnostic accuracy and reliability; however, several technical limitations still remain and the procedure is poorly tolerated by patients. The use of magnetic fields to control and steer endoscopic capsules is increasing in minimally invasive procedures. In fact, magnetic coupling is one of the few physical phenomena capable of transmitting motion beyond a physical barrier, allowing for the compact design of the device itself. In this framework, the authors present the preliminary design and assessment of a magnetic coupling for magnetic endoscopic capsules considering an electromagnetic approach. In particular, a novel toroidal electromagnet is proposed as the control and driving system. The system concept, design, and preliminary results are reported.

Vision and inertial-based image mapping for capsule endoscopy

Capsule endoscopy is a non-invasive procedure for gastrointestinal diagnosis. It does not require sedation and it is comfortable and well tolerated by patient. However, the problem with such procedure is that a huge number of images is collected, which require time to investigate and diagnose; furthermore, the capsule movement is not controlled leading, in some cases, to inaccurate diagnosis. In this context, a mapping of the lumen is required to guarantee a higher reliability of the inspection, enabling the medical doctor to evaluate all the parts of the lumen for a better diagnosis. In this paper, we propose a method for mapping images from a capsule-based endoscope: the technique uses visual and inertial-based data fusion to obtain a 3D map of the lumen from 2D capsule images, also paving the way for the implementation of a path planning and autonomous locomotion and inspection.

Ultrasound-based tracking strategy for endoluminal devices in cardiovascular surgery

Magnetic endovascular navigation of wireless or soft‐tethered endoluminal devices was recently proposed in the literature. This approach allows for innovative therapeutic procedures, but developing a real‐time tracking strategy, compatible with magnetic dragging, is a challenging problem and is not yet solved.

A computer-assisted robotic platform for Focused Ultrasound Surgery: Assessment of high intensity focused ultrasound delivery.

In the last century, medicine showed considerable advancements in terms of new technologies, devices and diagnostic/therapeutic strategies. Those advantages led to a significant reduction of invasiveness and an improvement of surgical outcomes. In this framework, a computer-assisted surgical robotic platform able to perform non-invasive Focused Ultrasound Surgery (FUS) - the FUTURA platform - has the ambitious goal to improve accuracy, safety and flexibility of the treatment, with respect to current FUS procedures. Aim of this work is to present the current implementation of the robotic platform and the preliminary results about high intensity focused ultrasound (HIFU) delivery in in-vitro conditions, under 3D ultrasound identification and monitoring. Tests demonstrated that the average accuracy of the HIFU delivery is lower than 0.7 mm in both X and Y radial directions and 3.7 mm in the axial direction (Z) with respect to the HIFU transducer active surface.

Trajectory analysis of endoscopic capsule images: A feasibility study

Standard endoscopy is a screening method that allows the detection of GI tract pathologies and lesions. However, it was demonstrated that endoscopy suffers from a significant miss rate for cancer detection. Therefore, there is a need to establish a standard protocol that can quantify the quality of endoscopic procedures, assist physicians in analyzing their performance and train them on how to select navigation techniques that result in different levels of quality inspection. In this paper, we propose a method to evaluate the performance of endoscopists by analyzing the trajectory produced by the endoscopic camera. The proposed method consists of three main modules: i) the image analysis module for estimating camera positions; ii) Kalman filter for estimating velocity and acceleration profiles; and iii) analysis module to analyze the trajectory based on the density of observed images and the acceleration profile. The approach was preliminary tested with a dataset of images collected from an ex-vivo experiment, with porcine tissue.

A computer-assisted robotic platform for vascular procedures exploiting 3D US-based tracking

Abstract Background: Cardiovascular diseases are the first cause of death globally: an estimated 17.5 million people died in 2012. By combining the benefits of magnetic navigation and ultrasound (US) imaging, the authors proposed a robotic platform (i.e. the MicroVAST platform) for intravascular medical procedures. Methods: A 3D imaging US-based tracking algorithm is implemented for the navigation of a magnetic-dragged soft-tethered device. Tests were performed to evaluate the algorithm in terms of tracking error and precision of locomotion. Results: The 3D imaging US-based algorithm tracked the endovascular device with an error of 6.4 ± 2.8 pixels and a mean displacement between the endovascular device and the preoperative path of 13.6 ± 4.5 mm (computational time of 12.2 ± 1.5 ms and 30.7 ± 6.1 matched features). Conclusions: The MicroVAST platform includes innovative solutions for navigation allowing for an assisted magnetic locomotion of medical devices in the cardiovascular district by combining a 3D imaging US-based tracking algorithm with pre-operative data.