JP2007111118A - Brain lesion diagnosis apparatus and method of using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately detect cerebral lesion signals (epilepsy focus, for instance) in a deep part inside the brain by a simple method in a short time lowly invasively to the body of a patient without performing an inspection craniotomy procedure before treatment. <P>SOLUTION: The cerebral lesion diagnosing apparatus comprises an endovascular electrode catheter 2 which can be inserted into an intracerebral blood vessel and is provided with at least one electrode 12 on the outer periphery of a distal end part, and an electroencephalograph 20. The electroencephalograph 20 is provided with a processing means 22 for processing potential data detected in the electrode 12 to data displayable as brain waves and a display means 24 for displaying the brain waves obtained in the processing means 22. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method and apparatus for measuring brain signals from within the body.

  In general, there are two types of measurement methods for electroencephalogram measurement. One is a method of installing an electrode for electroencephalogram measurement from above the scalp and a method of installing an electrode for electroencephalogram measurement in the skull. However, in the method of measuring the electroencephalogram from above the scalp, since “dura mater, cerebrospinal fluid, skull, scalp”, etc. enter between the electrode and the brain tissue, the electroencephalogram is 2 rather than the measurement on the surface of the brain tissue. It weakens to 1 / 5.00 / min. For this reason, noise increases and the recorded brain waves are limited to brain activities having a depth of about 5 mm to 1 cm from the surface of the brain.

  For this reason, in order to measure an electroencephalogram indicating brain activity in the deep part of the brain, it is necessary not to measure an electroencephalogram on the scalp but to measure it by placing electrodes on the surface of the brain tissue. Otherwise, detailed brain waves cannot be obtained, accurate diagnosis cannot be made, and appropriate treatment becomes difficult.

  In Japan, there are 1.2 million epilepsy patients, of which 25% are adults, 13% are children, and 17% are total (200,000). Of these, temporal lobe epilepsy is considered one of the best indications for surgical treatment. The focal point is the hippocampus that exists deep in the brain.

  The epilepsy diagnosis method is comprehensively determined from seizure symptoms, electroencephalogram during sleep, images, and the like. Direct surgery is possible when the seizure symptoms, electroencephalogram, and image findings are all consistent with abnormalities in one temporal lobe. However, if the electroencephalogram findings are not definitive or there is no difference between the left and right hippocampus in the image, an operation is performed, an intracranial electrode is placed inside the skull, and either of the left and right temporal lobes is epilepsy. It is necessary to decide whether it is the focus. That is, in temporal lobe epilepsy surgery, there are a two-stage structure (intracranial electrode placement method) in which a diagnostic operation is performed and then a therapeutic operation is performed, and a therapeutic operation can be performed suddenly.

  The intracranial electrode placement method is a method in which the skull is opened by surgery, the electrode is inserted to the immediate vicinity of the hippocampus along the surface of the brain, and then the surgical wound is closed once (see Non-Patent Document 1). ). For several days, 24 hours in a row, video electroencephalogram monitoring is performed from the placed electrode, the epilepsy focus distribution is accurately diagnosed, and therapeutic surgery is performed based on this result.

  The surgical treatment for temporal lobe epilepsy is called temporal lobe resection, which basically consists in resecting the epileptic focus centered on the hippocampus as a lump. Various methods have been devised to selectively remove only the focal point as much as possible. Since surgery is performed using a surgical microscope, safety is extremely high. Sequelae such as hemiplegia and speech impairment are extremely rare and rarely occur.

  In this temporal lobectomy, in order to selectively remove only the focal point as much as possible, it is necessary to accurately diagnose the epilepsy focal point distribution. Conventionally, intracranial electrode placement is often used. .

However, the intracranial electrode placement method is very invasive to the patient's body. That is, before undergoing therapeutic surgery, the epileptic focus needs to be accurately diagnosed and confirmed, and for that purpose it must undergo craniotomy for examination. Moreover, monitoring was performed for 24 hours with electrodes embedded for 7 to 10 days after surgery, and surgery for treatment was sometimes out of indication. There are also reports that intracranial electrode placement has a higher probability of complications than temporal lobectomy in some cases.
Hiroyuki Shimizu “Diagnosis and Surgery for Epilepsy” Asakura Shoten

  The present invention has been made in view of such a situation, and the object thereof is to perform brain in a simple manner in a short time and in a minimally invasive manner on a patient's body without performing a test craniotomy before treatment. It is intended to provide a brain lesion diagnostic apparatus capable of accurately detecting a brain lesion signal (for example, epilepsy focus) in a deep part of the brain, and a method of using the same.

In order to achieve the above object, a brain lesion diagnostic apparatus according to the present invention comprises:
An intravascular electrode catheter that can be inserted into a blood vessel in the brain and has at least one electrode portion on the outer periphery of the distal end;
Processing means for processing the potential data detected by the electrode section into data that can be displayed as an electroencephalogram,
Display means for displaying the electroencephalogram determined by the processing means;
Have

  In order to detect an electroencephalogram signal in the deep part of the brain using the brain lesion diagnostic apparatus according to the present invention, first, an intravascular electrode catheter is inserted from the arterial blood vessel of the hand or foot, and the distal end thereof is located in the deep part of the brain. Guide into the blood vessel. Since at least one electrode portion is attached to the distal end portion of the intravascular electrode catheter, the electrode portion is located deep in the brain.

  Next, the potential data detected by the electrode part located deep in the brain is sent to the processing means in the electroencephalograph located outside the body, and the processing means extracts the electroencephalogram data from the potential data. The brain wave data is displayed as a brain waveform on a display means such as a display. The diagnostician can read the brain lesion signal from the displayed electroencephalogram data and can accurately diagnose the epileptic focus position in the case of epilepsy, for example.

  The detected electroencephalogram data is automatically compared with the brain lesion signal stored in the storage means in the electroencephalograph, and a program can be set up to identify the disease name and lesion position automatically. It is. The brain lesion signal is not particularly limited, but is an electroencephalogram signal peculiar to the symptom caused by, for example, epilepsy, schizophrenia, Kreutfelds-Jakob disease, Alzheimer's disease, encephalitis, encephalopathy and the like.

  As described above, by using the apparatus according to the present invention, it is minimally invasive to a patient's body, without performing a test craniotomy before treatment, and in a short time (for example, 1 to 2 hours) and simple. The method can accurately detect brain lesion signals (e.g., epilepsy focus) deep in the brain.

  Preferably, a plurality of ring-shaped electrode portions are arranged at predetermined intervals along the longitudinal direction of the catheter on the outer periphery of the distal end portion of the intravascular electrode catheter. In order to accurately detect a brain lesion signal (for example, epileptic focus) in the deep part of the brain, it is preferable to simultaneously extract an electroencephalogram signal from electrode parts arranged at a plurality of positions in the deep part of the brain.

  Preferably, the width of the ring-shaped electrode portion is 0.1 to 3 mm, and the distance between adjacent ring-shaped electrodes is 20 mm or less. If the width of the electrode is too narrow, it tends to be difficult to detect an electroencephalogram signal. In addition, if the width of the electrode is too wide, it is difficult to specify the lesion site, and the flexibility of the distal end of the catheter tends to be lost. Loss of flexibility at the distal end of the catheter tends to make it difficult to enter the catheter into a narrow and tortuous vessel. If the distance between the electrodes is too wide, it is difficult to specify the lesion site, and it is difficult to specify the brain lesion signal.

  Further, since the intravascular electrode catheter is inserted into the intracerebral blood vessel having an extremely small inner diameter, the outer diameter of the intravascular electrode catheter is preferably 1 mm or less.

  Preferably, the processing means further includes noise removing means for removing a noise signal other than the electroencephalogram signal from the potential data detected by the electrode unit. The noise removing means is not particularly limited, and examples include a filter that cuts a specific frequency, and a means that cancels basic rhythm and pulse waves.

  The human / animal brain constantly generates electrical vibrations of various frequencies, and the basic potential oscillation is called basic rhythm. The pulse wave is a potential wave when a pressure change in a blood vessel generated when the blood is pushed into the aorta by contraction of the heart is transmitted in the peripheral direction. In order to accurately extract the target electroencephalogram, it is preferable to remove unnecessary noise signals other than these electroencephalograms.

  In the method for using the brain lesion diagnostic apparatus according to the present invention, at least one of isoflurane and sevoflurane is used as an inhalation anesthetic, and the brain lesion diagnostic apparatus described above is used under general anesthesia using the brain lesion diagnostic apparatus. Is preferably displayed. By using these drugs as inhalation anesthetics, brain lesion signals are likely to be generated, and the accuracy of diagnosis is improved.

Hereinafter, the present invention will be described based on embodiments shown in the drawings.
FIG. 1 is an overall configuration diagram of a brain lesion diagnostic apparatus according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of an essential part of an intravascular electrode catheter used in a brain lesion diagnostic apparatus according to another embodiment of the present invention,
Figure 3 is a schematic diagram of the brain,
FIG. 4 is a graph showing an example of an electroencephalogram before noise removal displayed by the display means of the electroencephalograph,
FIG. 5 is a graph showing an example of the electroencephalogram after noise removal displayed by the display means of the electroencephalograph.

  As shown in FIG. 1, the brain lesion diagnostic apparatus according to one embodiment of the present invention includes an intravascular electrode catheter 2 and an electroencephalograph 20. The intravascular electrode catheter 2 has a coil member 6 that is heat-sealed to the distal end portion of the catheter tube 4. The coil member 6 is made of metal such as Pt, Pt alloy, Au, Au alloy, W, W alloy, and SUS, and is excellent in flexibility and flexibility.

  The wire diameter of the coil member 6 is preferably 30 to 100 μm, and the winding outer diameter is 1 mm or less, preferably 0.2 to 0.6 mm. The axial length of the coil member 6 is preferably 10 to 50 mm.

  A hemispherical tip 8 is joined to the distal end of the coil member 6. The tip 8 is made of a metal such as SnAg, AuGe, AuSn, Pt, SUS, and the distal end of the wire 10 is joined by means such as brazing. The wire 10 extends in the axial direction inside the catheter tube 4. The wire 10 is made of a metal such as SUS or NiTi.

  Since the vascular traversing of the brain is so complex, the distal part of the catheter must follow the blood vessel, be flexible so as not to damage it, and have a smooth and less irritating tip structure. In addition, the blood vessels of the brain have a large number of branches, and therefore, blood vessel selectivity is necessary at the distal end of the catheter so that a safe and simple approach to the lesion site is possible.

  In the catheter 2 of the present embodiment, the wire 10 and the coil member 6 are configured at the distal end portion thereof, so that these requirements can be sufficiently satisfied. In addition, in order to improve blood vessel selectivity at the distal end portion of the catheter 2, the distal end portion of the wire 10 may be brazed in an L shape.

  On the outer periphery of the distal end portion of the catheter tube 4, a ring electrode 12 having a predetermined width W1 is disposed at a predetermined interelectrode distance L1. Each ring-shaped electrode 12 is composed of an X-ray contrast metal ring such as Pt, Pt alloy, Au, or Au alloy. Each ring electrode 12 is embedded in the outer periphery of the catheter tube 4 and has an outer diameter substantially the same as the outer diameter of the catheter tube 4.

  The outer diameter of the catheter tube 4 is 1 mm or less, preferably 0.2 to 0.7 mm. The catheter tube 4 is made of a synthetic resin such as polyolefin, polyamide, polyether polyamide, or polyurethane.

  The axial width W1 of each ring-shaped electrode 12 is preferably 0.1 to 3 mm, and the inter-electrode distance L1 is 20 mm or less, preferably 5 to 10 mm. The ring-shaped electrode 12 located on the most distal end side is located at a position where the distance L0 from the tip 8 is preferably 0 to 10 mm. The number of arrangement of the ring-shaped electrodes 12 is not particularly limited, but is preferably 2 to 4.

  The catheter tube 4 has, for example, a length longer than the length from the artery of the human arm or leg to the cerebral blood vessel, and a connector (not shown) is attached to the proximal end of the catheter tube 4. is there. The connector is located outside the body in use, and a lead wire 14 of a conductive wire electrically connected to each electrode 12 is drawn out from the connector.

  The leader line 14 is connected to an electroencephalograph 20 as shown in FIG. The electroencephalograph 20 includes processing means 22 that processes the potential data detected by the ring electrode 12 into data that can be displayed as an electroencephalogram. The processing means 22 extracts electroencephalogram data from the potential data detected by the electrode 12. The brain wave data is displayed as a brain waveform on the display means 24 such as a display.

  The processing unit 22 further includes a noise removing unit 23 that removes a noise signal other than the electroencephalogram signal from the potential data detected by the electrode unit. Although it does not specifically limit as the noise removal means 23, The means which cancels the filter which cuts a specific frequency, a basic rhythm, a pulse wave, etc. are illustrated.

  The human / animal brain constantly generates electrical vibrations of various frequencies, and the basic potential oscillation is called basic rhythm. The pulse wave is a potential wave when a pressure change in a blood vessel generated when the blood is pushed into the aorta by contraction of the heart is transmitted in the peripheral direction. In order to accurately extract the target electroencephalogram, it is preferable to remove unnecessary noise signals other than these electroencephalograms.

  For example, FIGS. 4 and 5 show the waveform of an electroencephalogram displayed on the display of the electroencephalograph 20 and noise signals such as basic rhythm and pulse wave. FIG. 4 shows the waveform of the electroencephalogram before noise removal, and FIG. 5 shows the waveform of the electroencephalogram after noise removal.

  The storage means 26 shown in FIG. 1 is a part for storing the electroencephalogram data processed by the processing means 22. The storage means 26 may store a normal brain wave and an abnormal brain wave in advance. The processing means 22 compares the electroencephalogram data sequentially processed with the normal electroencephalogram and the abnormal electroencephalogram stored in the storage means 26, and when the detected electroencephalogram matches the abnormal electroencephalogram, It may be programmed to issue an alarm automatically.

  Alternatively, the storage means 26 may store a program for specifying the position of the brain where abnormal brain waves are detected. For example, the abnormal position of the brain can be identified based on the electroencephalogram signals detected from the plurality of electrodes 12 attached to the distal end portion of the catheter 2.

  Note that the abnormal brain wave in the case of epilepsy has a sharper and larger peak than the normal brain wave.

  In order to detect an electroencephalogram signal in the deep part of the brain using the brain lesion diagnostic apparatus according to the present embodiment, first, the intravascular electrode catheter 2 shown in FIG. Lead the end into the blood vessel located deep in the brain. Since a plurality of electrodes 12 are attached to the distal end portion of the intravascular electrode catheter 2, the electrodes 12 are located deep in the brain. For example, the distal end of the intravascular electrode catheter 2 can be guided into a blood vessel located near the pair of hippocampus 32 in the deep part of the brain 30 shown in FIG.

  Next, the potential data detected by the electrode 12 located deep in the brain is sent to the processing means 22 in the electroencephalograph 20 located outside the body, and the processing means 22 uses the potential data to remove the noise removing means 23. To remove noise and extract brain wave data. The brain wave data is displayed as a brain waveform on the display means 24 such as a display. An example of the electroencephalogram after noise removal is shown in FIG.

  The diagnostician can read the brain lesion signal from the displayed electroencephalogram data and can accurately diagnose the epileptic focus position in the case of epilepsy, for example.

  As described above, by using the brain lesion diagnostic apparatus of the present embodiment, it is minimally invasive to a patient's body without performing a test craniotomy before treatment in a short time (for example, 1 to 2 hours). Moreover, it is possible to accurately detect a brain lesion signal (for example, epileptic focus) in the deep part of the brain by a simple method.

  Moreover, when using this brain lesion diagnostic apparatus, it is preferable for a patient to use at least one of isoflurane and sevoflurane as an inhalation anesthetic and detect an electroencephalogram signal under general anesthesia. By using these drugs as inhalation anesthetics, brain lesion signals are likely to be generated, and the accuracy of diagnosis is improved.

  The present invention is not limited to the above-described embodiment, and can be variously modified within the scope of the present invention.

  For example, the intravascular electrode catheter used in the brain lesion diagnostic apparatus according to the present invention is not limited to the embodiment shown in FIG. 1, and various types of catheters can be used. FIG. 2 is a cross-sectional view of an essential part of an intravascular electrode catheter 2a according to another embodiment of the present invention.

  As shown in FIG. 2, in this catheter 2a, not a coil member 6 but a resin rod 6a is heat-sealed to the distal end portion of the catheter tube 4a. The distal end of the wire 10 is joined to the resin rod 6a.

  The resin rod 6a is made of, for example, a synthetic resin such as polyurethane or silicon, and the outer diameter and axial length thereof are substantially the same as the outer diameter and axial length of the coil member 6 shown in FIG.

  As the wire 10 shown in FIG. 2, the same wire 10 as shown in FIG. 1 can be used. As the catheter tube 4a shown in FIG. 2, the same tube as the catheter tube 4 shown in FIG. 1 can be used. The resin rod 6a has a rounded tip, is flexible so as to follow a blood vessel and does not damage it, and has a smooth and less irritating tip structure.

  The other structure is the same as that of the embodiment shown in FIG. 1, and a plurality of ring electrodes 12 (not shown) are mounted on the outer periphery of the distal end portion of the catheter tube 4a. Also in the present embodiment, the same operational effects as those of the apparatus shown in FIG. 1 can be obtained.

FIG. 1 is an overall configuration diagram of a brain lesion diagnostic apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of an essential part of an intravascular electrode catheter used in a brain lesion diagnostic apparatus according to another embodiment of the present invention. FIG. 3 is a schematic diagram of the brain. FIG. 4 is a graph showing an example of an electroencephalogram before noise removal displayed by the display means of the electroencephalograph. FIG. 5 is a graph showing an example of the electroencephalogram after noise removal displayed by the display means of the electroencephalograph.

Explanation of symbols

2, 2a ... intravascular electrode catheter 4, 4a ... catheter tube 10 ... wire 12 ... ring electrode 20 ... electroencephalograph 22 ... processing means 23 ... noise removing means 24 ... display means 26 ... storage means

Claims (6)

An intravascular electrode catheter that can be inserted into a blood vessel in the brain and has at least one electrode portion on the outer periphery of the distal end;
Processing means for processing the potential data detected by the electrode section into data that can be displayed as an electroencephalogram,
Display means for displaying the electroencephalogram determined by the processing means;
A brain lesion diagnosis apparatus having:   The brain lesion diagnosis apparatus according to claim 1, wherein a plurality of ring-shaped electrode portions are arranged at predetermined intervals along the longitudinal direction of the catheter on the outer periphery of the distal end portion of the intravascular electrode catheter.   The brain lesion diagnostic apparatus according to claim 2, wherein a width of the ring-shaped electrode portion is 0.1 to 3 mm, and a distance between adjacent ring-shaped electrodes is 20 mm or less.   The brain lesion diagnostic apparatus according to any one of claims 1 to 3, wherein an outer diameter of the intravascular electrode catheter inserted into the cerebral blood vessel is 1 mm or less.   The brain lesion diagnosis apparatus according to claim 1, wherein the processing unit further includes a noise removing unit that removes a noise signal other than an electroencephalogram signal from the potential data detected by the electrode unit. Brain lesion diagnosis using at least one of isoflurane and sevoflurane as an inhalation anesthetic and displaying an electroencephalogram signal using the brain lesion diagnostic apparatus according to any one of claims 1 to 5 under general anesthesia How to use the device.

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