Positioning system for an imaging device

Patent metadata

Field	Value
Publication number	US-11298206-B2
Application number	US-201715728794-A
Country	US
Kind code	B2
Filing date	Oct 10, 2017
Priority date	Oct 27, 2016
Publication date	Apr 12, 2022
Grant date	Apr 12, 2022

Abstract

A positioning system for an imaging device, in particular a MR imaging device to position an insertion element on or in the body of a subject, in particular an animal, wherein the imaging device comprises a bore, in which the subject is received, wherein the positioning system comprises a robot which can be at least partially arranged in the bore of the imaging device and comprises a holding element to hold the insertion element; wherein the robot further comprises at least one actuator acting on the holding element, such that an end portion of the insertion element is movable, wherein said at least one actuator is arranged with a distance D from the bore to minimize magnetic and/or electromagnetic interferences between the imaging device and the at least one actuator and said first actuator is coupled to the holding element in a form-fit- and/or a force-fit-manner.

First claim

We claim:

1. A positioning system for positioning an insertion element on or in the body of a subject, the positioning system comprising an imaging device, wherein the imaging device comprises a bore, in which the subject is received, wherein the positioning system further comprising a robot, which is at least partially arranged in the bore of the imaging device and comprises a holding element to hold the insertion element; wherein
the robot further comprises at least one actuator, wherein said at least one actuator is arranged with a distance D from the bore to minimize magnetic and/or electromagnetic interferences between the imaging device and a first actuator of the at least one actuator, wherein said distance D is between 1.5 and 4.7 meters, and said first actuator is coupled to the holding element in a form-fit- and/or a force-fit-manner;
wherein the coupling of the first actuator to the holding element in the form-fit and/or the force-fit-manner is achieved by a belt drive, wherein a first belt is looped over a first pulley and a pulley connected to the first actuator, and wherein the connection between the first belt and the first pulley is in a form-fit manner and said first actuator acts on the holding element via the first belt and first pulley such that the end portion of the insertion element is linearly movable;

wherein the bore has a longitudinal expansion along an X-axis and further expands along a Z-axis and a Y-axis, wherein said X-axis, Y-axis and Z-axis are orthogonal to each other, wherein at least the end portion of the insertion element has a longitudinal extension along an A-axis, wherein the A-axis and the Z-axis form an angle α, which is in the range between −90° and +90°;
wherein the robot comprises a head part, a first and a second drive mechanism, wherein the first actuator acts on the holding element via the first drive mechanism such that the end portion of the insertion element is linearly movable along the A-axis, wherein a second actuator of the at least one actuator acts on the holding element via the second drive mechanism such that the end portion of the insertion element can be pivoted about a pivot axis B, wherein by said pivoting-motion the angle α is adjusted; and
wherein the second drive mechanism comprises a second pulley, which is connected to the second actuator by a second belt, and a cup element, which is rigidly connected to the second pulley, wherein the cup element comprises a receiving element, which extends along an A-axis and receives the holding element, wherein the cup element engages the holding element such that a rotational motion of the cup element causes a pivoting-motion of the holding element around a B-axis.

2. The positioning system according to claim 1 , wherein
the imaging device is a functional magnetic resonance imaging (fMRI)-device comprising a magnetic resonance imaging (MRI) scanner, using a magnetic field in the range of ca. 3 T to ca. 21 T, and a bore diameter in the range of 12 cm to 6 cm, wherein the insertion element is selected from the group consisting of: a fiber-optic for optogenetic stimulation and fluorescent recording from endogenous biosensors of metabolites of the subject brain or exogenous biosensors of metabolites of the subject brain, an electrode for recording electrophysiological or electrochemical signal, and an implantable pump or needle for direct drug delivery to treat tumor or other diseases.

3. The positioning system according to claim 1 , wherein
the first drive mechanism comprises the first pulley, which is connected to the first actuator by the first belt, a shaft, which is received in a central hub portion of the first pulley and connects the first pulley and a converting element, on which the holding element is mounted, wherein the converting element converts a rotational motion of the first pulley into a linear motion of the holding element along the A-axis.

4. The positioning system according to claim 3 , wherein
the converting element comprises a disc element with a first surface on which a first guiding element is arranged, wherein the holding element comprises at least one second guiding element, which engages the first guiding element.

5. The positioning system according to claim 4 , wherein
the first guiding element has a continuous course, which originates in or in the proximity of a center of the disc element, wherein the continuous course evolves in form of a spiral to an edge of the disc element, wherein the spiral is described by a polar equation of r=a*θ, wherein r is the radial distance, θ is the polar angle and a is a constant >0.

6. The positioning system according to claim 1 , wherein
the head part of the robot is connected to a holding rod via a connection element, wherein the robot further comprises a third actuator of the at least one actuator which acts on the holding rod via a third drive mechanism, such that the head part of the robot can be moved along the Y-axis, wherein the robot further comprises a fourth actuator of the at least one actuator which acts on the holding rod via a fourth drive mechanism, such that the head part of the robot can be moved along the X-axis.

7. The positioning system according to claim 6 , wherein
the third drive mechanism comprises a third pulley, which is connected to the third actuator by a third belt, wherein the third pulley is rigidly connected to a threaded spindle on which a nut is arranged, wherein the nut is connected to the holding rod of the robot, wherein the threaded spindle is arranged perpendicularly to the holding rod, wherein a rotation of the third pulley causes a rotation of the threaded spindle and a movement of the nut and the holding rod along the Y-axis.

8. The positioning system according to claim 7 , wherein
the positioning system comprises a platform, on which the robot is arranged, wherein the subject is suspended and/or held at a head part of the platform, which can be arranged in the bore of the imaging device, wherein the first, second, third and fourth actuators are arranged at a foot part of the platform, wherein the threaded spindle is arranged on a holder connected to the platform.

9. The positioning system according to claim 8 , wherein
the robot and the platform mainly consist of MRI-compatible materials, such as nonmagnetic, dielectric materials, plastics, rubbers, ceramics.

10. The positioning system according to claim 8 , wherein
the positioning system comprises at least one MRI-compatible camera, which is mounted on the head part of the platform.

11. The positioning system according to claim 8 , wherein
the positioning system further comprises a navigation unit comprising a control unit, which controls the motion of the first, second, third and fourth actuator, an image processing unit, which processes real time images of the imaging device and/or an at least one camera in the bore.

12. A method to position an insertion element using a positioning system according to claim 1 in a magnetic resonance (MR) imaging device, the method comprising the steps of:
a. lowering the insertion element by the robot to a first position on the subject or close to the subject;
b. acquiring a three-dimensional-magnetic resonance imaging (3D-MRI) image and processing the image via an image processing unit to identify the location of the subject, as well as the position of the insertion element;
c. calculating the coordinates of a target point and the insertion element and calculating an optimized movement trajectory for the insertion element by a control unit;
d. monitoring the movement trajectory by the real-time MRI image via the image processing unit.

Assignees

• Massachusetts Gen Hospital

Inventors

• Chen Yi
• Yu Xin
• Yu Shanyi

Classifications

• A61B5/055 Primary

  involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging · CPC title

• A61B90/50 Primary

  Supports for surgical instruments, e.g. articulated arms · CPC title

• A61B5/0084

  for introduction into the body, e.g. by catheters (A61B5/1459 takes precedence) · CPC title

• G01R33/4808

  Multimodal MR, e.g. MR combined with positron emission tomography [PET], MR combined with ultrasound or MR combined with computed tomography [CT] · CPC title

• G01R33/286

  involving passive visualization of interventional instruments, i.e. making the instrument visible as part of the normal MR process · CPC title