JPH10277001A - Intracelom mr probe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intracelom MR probe made small-sized constitution whose manufacture cost is lower than conventional one. SOLUTION: This intracelom MR probe 1 is provided with an insertion part 3 insatiable into a celom and the magnetic susceptibility of the insertion part 2 is a value capable of considering that magnetic resonance tomographic image distortion accompanying the disturbance of magnetostatic field uniformity generated by a magnetic resonance homograph does not affect diagnoses or treatments. An operation part 3 connected to the insertion part 2 is constituted of the member of the magnetic susceptibility higher than the insertion part 2 and the insertion part 2 and the operation part 3 are freely attachably and detachably disconnected the time of magnetic resonance tomography.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic resonance tomography apparatus and, more particularly, to an in-body MR probe inserted into a body cavity during magnetic resonance tomography.

[0002]

2. Description of the Related Art Japanese Patent Laid-Open Publication No. Hei 7-303625 proposes an intra-cavity MR probe having a receiving coil built in at the distal end of an insertion portion of an endoscope or the like. The magnetic susceptibility of the portion is set to a value within a range in which the magnetic resonance tomographic image distortion does not affect diagnosis and treatment, while the magnetic susceptibility of the other portions is set to a value within a range not attracted to the static magnetic field generated by the magnetic resonance tomography apparatus. It is formed of a material having a value larger than the magnetic susceptibility of the side portion.

[0003]

Problems to be Solved by the Invention Japanese Patent Laid-Open No. Hei 7-30362
In the intracorporeal MR probe proposed in Japanese Patent Publication No. 5 (1993), portions other than the distal end portion of the insertion portion are made of a material having a value larger than the susceptibility of the distal end portion. SUS31 of titanium, brass, ceramic, plastic, austenitic stainless steel
0 or SUS306.

However, since ceramics, plastics, and brass have low strength, members must be thick and large to guarantee the strength. Since titanium itself is expensive and difficult to process, the cost of processing is also high, so that titanium is generally quite expensive. Further, even in the case of stainless steel, if cutting is performed, the magnetization tends to increase, so that the processing method is limited, and the processing cost is increased, so that the cost tends to be high.

Therefore, when the present invention is applied to an endoscope having a conventional general structure and used in a magnetic resonance tomography apparatus, its components become considerably expensive and the operation section becomes large. And it may be difficult to handle. SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide an intracorporeal MR probe which is less expensive to manufacture and has a smaller configuration.

[0006]

Means and Action for Solving the Problems

(Constitution) The present invention has an insertion portion that can be inserted into a body cavity,
The magnetic susceptibility of this insertion portion is such a value that magnetic resonance tomographic image distortion due to disturbance of the static magnetic field uniformity generated by the magnetic resonance tomography apparatus does not affect diagnosis or treatment, and is connected to the insertion portion. The operation section is formed of a member having a higher magnetic susceptibility than the insertion section, and the insertion section and the operation section are detachably detachable from each other.

(Operation) An MR probe in a body cavity is inserted at a place away from the magnetic resonance tomography apparatus. When the positioning in the body cavity is completed, the operation unit having a high magnetic susceptibility is separated from the insertion unit, and only the insertion unit that does not affect the diagnosis / treatment is left in the body cavity. After disconnecting the operation unit from the insertion unit, the subject is moved into the gantry of the magnetic resonance tomography apparatus to start magnetic resonance tomography. Since the magnetic susceptibility of the insertion portion is small, there is no adverse effect on diagnosis and treatment.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] A first embodiment of the present invention will be described with reference to FIGS. (Structure) FIG. 1 is an explanatory view schematically showing the whole intracavity MR probe 1 according to the first embodiment. Here, the intracavity MR probe 1 constitutes an endoscope. That is, M in the body cavity
The R probe 1 includes an insertion section 2 inserted into a body cavity, an operation section 3 held by an operator, a connection section 4 configured between the operation section 3 and the insertion section 2, and an operation section 3. An eyepiece 5 is provided at a hand end of the operation unit 3. The insertion portion 2 is formed by connecting the distal end portion 6, the bending portion 7, and the flexible tube 8 in order from the distal end portion inserted into the body cavity. The main body member of the connecting portion 4 is attached to the proximal end of the insertion portion 2.
A base 9 is provided for inserting and sending a treatment instrument or member to the distal end side of the insertion portion through a channel described later formed therein, or for supplying and discharging a liquid, and a current supply cord 10 is connected thereto. A light source cord 11 for connecting to an endoscope light source device (not shown) is connected to the operation unit 3, and an extension end of the light source cord 11 is detachably attached to the endoscope light source device (not shown). Light source connector 12
Is provided. Further, a variable current supply means 13 is connected to the end of the cord 10. Variable current supply means 1
A foot switch 14 is connected to 3 so that the surgeon can adjust the amount of current supply without directly using it by hand.

The insertion section 2 of the intracavity MR probe 1 is configured as shown in FIG. First, the member of the distal end portion 6 is formed of a resin such as polysulfone which is safe for a living body and is a non-magnetic material. The insertion portion 2 is included in the member of the tip portion 6.
Optical system 15 and illumination optical system 1 for observing the front of
6, and an opening 17 for guiding the treatment tool into the body cavity under magnetic resonance tomography. The opening 17 is in communication with the base 9 in the connection section 4 via a channel tube 18. The channel tube 18 is made of a non-magnetic material having high water resistance such as thick silicon and Teflon. Objective optical system 15
Is connected to the eyepiece unit 5 via the glass fiber bundle 19 for image guide, and transmits an image in the body cavity. The illumination optical system 16 is connected to the light source connector 12 via a light guide glass fiber bundle 20.
The light guide glass fiber bundle 20 transmits light from a light source device (not shown) to the illumination optical system 16 at the tip of the insertion section 2.
It leads to.

The distal end 6 is connected to a flexible tube 8 through a curved portion 7.
However, the curved tube 7 has a more flexible structure than the flexible tube 8. In the case of the present embodiment, the bending portion 7 and the flexible tube 8 are formed of the same material resin tube 21, and only the region of the bending portion 7 is thinned so that the region of the bending portion 7 is more flexible than the flexible tube 8. It is flexible. However, it is sufficient that the bending portion 7 has a structure that bends with a smaller force than the flexible tube 8. For example, a resin tube shape having the same thickness may be a braided copper alloy wire other than the portion to be bent. And the hardness may be set relatively high by embedding. Further, a weak magnetic material such as titanium, titanium alloy, austenitic stainless steel, copper, or aluminum alloy may be used as the reinforcing material. When flexibility is not required for the soft tube 8, the hard pipe made of the weak magnetic material may be used in place of the soft tube 8 to make the portion a hard portion.

A conductor wire 22 is inserted into the insertion portion 2 and folded up to the distal end portion of the curved portion 7. Both ends of the conductor wire 22 are variable via the connection portion 4 and the cord 10. It is connected to the current supply means 13. Conductor wire 2
Reference numeral 2 denotes a magnetic shield 23 provided over the entire length except for one portion in the curved portion 7, so that the magnetic shield 23 is not affected by the magnetic resonance tomography apparatus. The distal end of the conductor wire 22 is fixed to the inner surface of the resin tube 21 with an adhesive 24 at the distal end portion of the curved portion 7.

Since the operating section 3 is also a gripping portion that is gripped by a surgeon's hand, the operating section 3 needs to have strength to support the entire weight of the intra-cavity MR probe 1, and its exterior or internal members are strong. It is made of stainless steel and contains magnetic material.

The insertion section 2 of the intracavity MR probe 1 can be attached to and detached from the operation section 3 by a connection section 4 described below. FIG. 3 shows a connection boundary portion between the connection unit 4 and the operation unit 3. The connecting portion 4 is made of a titanium alloy so as not to disturb the magnetic field, but may be made of a weak magnetic material such as austenitic stainless steel or an aluminum alloy as long as it does not easily disturb the magnetic field.

A connection ring 25 is provided on the end face of the operation part 3 on the connection part 4 side. Correspondingly, a connection ring 25 is fitted on the end face of the main body member of the connection part 4. A joining portion 26 is formed. The fitting section 26 is provided with a fitting hole 27, and the connection ring 25 of the operation section 3 is provided with a detachable pin 28 that fits into and engages with the fitting hole 27. An image guide relay connector 31 and a light guide relay connector 32 are provided on the inside of the connection ring 25 of the operation unit 3.

The image guide relay connector 31 and the light guide relay connector 32 are provided in the insertion section 2 by connecting the insertion section 2 of the intracavity MR probe 1 to the operation section 3 via the connection section 4. The image guide glass fiber bundle 19 and the light guide glass fiber bundle 20 are connected to respective base ends of the image guide glass fiber bundle 19 and the light guide glass fiber bundle 20. To connect to.

On the other hand, when the insertion portion 2 of the intracavity MR probe 1 is separated from the operation portion 3, the image guide relay connector 31 and the light guide relay connector 32 are provided.
Thus, the image guide glass fiber bundle 19 and the light guide glass fiber bundle 20 on the insertion section 2 side of the intracavity MR probe 1 are separated from each other.

(Operation) First, a guide operation is performed while viewing the optical image obtained from the eyepiece section 5 of the intracavity MR probe 1 at a location away from the main body of the magnetic resonance tomography apparatus, and the guide operation is performed.
The insertion section 2 of the R probe 1 is inserted into the body cavity of the subject.
After completion of the insertion, the operation unit 3 having a high magnetic susceptibility is separated from the insertion unit 2. This disconnection operation is performed by the connection ring 2 of the operation unit 3.
If the connection portion 4 and the operation portion 3 are pulled after pulling the detachable pin 28 in 5 and pulling it out from the fitting hole 29, the connection between the connection ring 25 and the fitting portion 26 is released, and the connection can be released.
After removing the operation unit 3, the subject is placed in the gantry of the magnetic resonance tomography apparatus main body, and magnetic resonance tomography is started. If it is necessary to adjust the position of the distal end of the insertion portion 2 of the intracavity MR probe 1 during this imaging, the surgeon operates the foot switch 14 to supply current to the conductor wire 22 from the variable current supply means 13. Thereby, the bending portion 7 is bent and adjusted.

FIG. 4 shows the principle that the bending portion 7 bends. That is, a magnetic field is always generated in a certain direction in the country of the magnetic resonance tomography apparatus (not shown).
For example, in FIG. 4, it is assumed that a magnetic force line 33 passes in a direction perpendicular to the paper surface and passes from the front side to the back side of the paper surface. In this case, when the current I flows from the variable current supply means 13 to the conductor wire 22 in the direction shown in FIG. 4, a force F acts on the conductor wire 22 in the direction shown in FIG. The conductor wire 22 has a curved portion 7
The other part is a magnetic shield 23
In addition, since the conductor wire 22 is fixed at the distal end portion of the curved portion 7, when the conductor wire 22 receives the force F, the distal end tends to move downward in the drawing. As a result, only the thin curved portion 7 bends. The position of the distal end portion 6 can be adjusted by bending the bending portion 7. The bending direction can be easily changed by the surgeon changing the direction of the insertion section 2 or changing the output polarity of the variable current supply means 13. Further, by changing the output of the variable current supply means 13, the Lorentz force applied to the conductor wire 22 also changes, so that the bending angle can be adjusted.

(Effect) The operation unit 3 is detachable, and the operation unit 3 can be configured without considering the influence of the magnetic force. As a result, since a ferromagnetic material such as stainless steel which is generally used can be used, a small in-body MR probe 1 having high strength and low manufacturing cost can be realized.

Since the insertion portion 2 can be made of a weak magnetic or non-magnetic material, the inspection portion can be safely inspected and treated without being moved by the influence of magnetic force in the body cavity during magnetic resonance tomography. became.

Since the bending operation of the bending portion 7 can be performed by the Lorentz force applied to the conductor wire to which the current has been applied, the lightweight intracavity MR probe 1 without a complicated mechanism such as wire pulling can be realized. In particular, the intracavity MR probe 1 that can be easily bent even in a magnetic resonance tomography apparatus can be realized.

Since it is not necessary to provide a mechanical bending mechanism for the insertion section 2 in the operation section 3, the size and weight can be reduced. Further, even when the operation unit 3 is separated, the tip shape is maintained in the gantry of the magnetic resonance tomography apparatus main body, so that the inspection is facilitated.

[Second Embodiment] A second embodiment of the present invention will be described with reference to FIGS. (Construction) In this embodiment, the insertion portion 2 of the intracavity MR probe 1 is used.
The receiving antenna 41 for magnetic resonance tomography is built in the distal end portion 6 in FIG. The rear end side line of the receiving antenna 41 is connected to a cable 42 led out from the connecting portion 4 via the insertion portion 2 and the inside of the connecting portion 4. The extension end of the cable 42 is connected to a magnetic resonance tomography apparatus (not shown). Further, a magnetic member 43 such as a magnet is attached inside the operation unit 3. An iron core 44 is provided beside the magnetic member 43, and a coil 45 is wound around the outer periphery of the iron core 44. Both end lines of the coil 45 are inserted into a tube 46 extended from the operation unit 3 and connected to a DC power supply 47. Others are the same as those of the first embodiment.

(Operation) In addition to the operation similar to that of the first embodiment, an MR signal is received from the receiving antenna 41, and this signal is manually input to a magnetic resonance tomography apparatus to perform magnetic resonance tomography. As shown in FIG. 6A, the removed operation unit 3
Is fixed to the gantry wall 48 via the magnetic member 43.
After the inspection, a current is passed by the DC power supply 47,
As shown in FIG. 6B, the iron core 44 serves as an electromagnet, and a repulsive force F ′ for separating the operation unit 3 from the gantry wall 48 works, so that the operator can easily remove it.

(Effect) In addition to the above-described first embodiment,
The following effects can be obtained. First, the receiving antenna 41
By placing in the body cavity, a detailed magnetic resonance tomography near the distal end of the insertion section 6 was obtained. Further, since the bending operation can be remotely controlled by a foot switch, a magnetic resonance tomographer in another room can adjust the position of the distal end of the MR probe 1 in the body cavity while viewing the tomographic image. Further, since the operation section 3 removed from the insertion section 2 can be adsorbed to the gantry wall 48, it is not necessary to consider a place where the removed operation section 3 is placed.

<Supplementary Notes> It has an insertion part that can be inserted into the body cavity, and the magnetic susceptibility of this insertion part is such that the magnetic resonance tomographic image distortion caused by disturbance of the uniformity of the static magnetic field generated by the magnetic resonance tomography apparatus does not affect diagnosis or treatment Wherein the operating portion connected to the insertion portion is formed of a member having a higher magnetic susceptibility than the insertion portion, and the insertion portion and the operation portion are detachably detachable. MR probe. 2. 2. An intracorporeal MR probe according to claim 1, wherein a part of the member used for the insertion portion is made of a weak magnetic metal such as titanium, titanium alloy, austenitic stainless steel, copper, copper alloy, and aluminum alloy. . 3. 8. The intracorporeal MR probe according to claim 1, wherein the operation section can be removed while maintaining the distal end position of the insertion section. 4. 2. An intracorporeal MR probe according to claim 1, wherein an MR antenna is built in the distal end portion of the insertion portion. 5. It has an inserted part that can be inserted into the body cavity, and the magnetic susceptibility of this inserted part is affected by the magnetic resonance sectional image distortion caused by the disturbance of the static magnetic field uniformity generated by the magnetic resonance tomography apparatus, which affects the diagnosis or treatment The operating portion connected to the insertion portion is made of a member having a higher magnetic susceptibility than the insertion portion. A conductor wire is arranged at the tip of the insertion portion, and the tip of the conductor wire is fixed at the tip in a state where it is magnetically shielded except for the bending portion of the insertion portion, and a variable current is applied to the bending portion conductor wire. An intracorporeal MR probe to which supply means is connected.

(Problem of Appendix 5) JP-A-7-30362
No. 5 discloses a bendable endoscope used in combination with a magnetic resonance tomography apparatus. However, it shows that a wire is mechanically pulled as a mechanism for bending in a body cavity, and the operating section has a built-in mechanism for bending. If this method is adopted, a large number of members must be built in the operation unit, and the weight becomes heavy. In addition, since the wire is pulled, each component must be strong enough to withstand the force, especially if it is made of a non-magnetic or weak magnetic material, the component itself becomes large and the operation unit itself is difficult to handle. There was a risk of becoming something.
According to the additional item 5, the problem can be solved.

[0028]

As described above, according to the present invention, since the operating member can be constituted irrespective of the magnetic susceptibility of the operating member, the manufacturing cost is lower than that of the prior art and the compact intra-cavity MR. A probe can be realized.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram schematically showing an entire intracavity MR probe according to a first embodiment.

FIG. 2 is a vertical cross-sectional view of the in-body MR probe according to the first embodiment, taken along the insertion axis near the distal end of the insertion portion.

FIG. 3 is a perspective view showing a state in which a connection portion and an operation portion of the intracavity MR probe according to the first embodiment are separated.

FIG. 4 is an explanatory diagram of a principle that a curved portion of the intracavity MR probe according to the first embodiment is curved.

FIG. 5 is an explanatory view schematically showing the whole intracavity MR probe according to the second embodiment.

FIG. 6 is an explanatory diagram of an operation of an operation unit in the in-body cavity MR probe according to the second embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... MR probe in a body cavity, 2 ... insertion part, 3 ... operation part, 4
... connecting part, 6 ... tip part, 7 ... bending part, 8 ... soft tube.

Claims (1)

[Claims] The present invention has an insertion portion which can be inserted into a body cavity, and the magnetic susceptibility of the insertion portion can be used for diagnosis or treatment of magnetic resonance tomographic image distortion accompanying disturbance of static magnetic field uniformity generated by a magnetic resonance tomography apparatus. It is a value that can be regarded as not affecting, and that the operation unit connected to the insertion portion is formed of a member having a higher magnetic susceptibility than the insertion portion, and that the insertion portion and the operation portion can be detachably detached. Characteristic MR probe in body cavity.