JPS5847183B2 - urinary pacemaker - Google Patents

Description

Detailed Description of the Invention This invention automatically detects the amount of urine stored in a living body, notifies this state when the amount of stored urine exceeds a predetermined value, and stimulates the bladder by the patient's own operation. This invention relates to a urinary pacemaker configured to perform urination by giving a

In recent years, the number of patients suffering from urinary incontinence or difficulty urinating due to spinal cord injury due to traffic accidents, industrial accidents, etc. has been increasing, and the hardships faced by these patients and the eight people around them are enormous. There is a strong social desire for a good treatment for this problem.

However, although research has been conducted in the urinary field for this type of symptom, the behavior of the micturition reflex system has not been fully elucidated due to the complexity of the micturition reflex innervation nerves, and there are no satisfactory treatment methods. There wasn't.

In cystic paralysis (neurogenic bladder), which is generally caused by spinal cord injury, the bladder does not contract and the patient is unable to sense the urge to urinate.

Conventionally, devices are known that simply contract the bladder by applying electrical stimulation to the bladder muscles, but it is difficult to accurately detect the amount of urine stored in the bladder and perform metabolism under the most suitable conditions for the body. could not.

Furthermore, when electrical stimulation is applied to the bladder muscle, if the leakage current is large, the urethral sphincter muscle contracts, causing urination to be interrupted even though the intravesical pressure increases.

As a result of intensive research to overcome these conventional drawbacks, the inventors have developed a system that automatically detects the amount of urine stored in the bladder, and when the amount of stored urine exceeds a predetermined value, the condition is detected by the patient. We succeeded in developing a micturition pacemaker that provides electrical stimulation to the bladder and causes the patient to urinate based on this notification.

In other words, as a means of detecting the amount of urine stored, at least one pair of positive and negative electrodes is placed on opposing bladder walls by suturing or the like, and changes in the amount of stored urine are detected between the electrodes based on the stretching of the bladder. An oscillation circuit that detects resistance changes and variably adjusts the oscillation frequency based on this resistance change is embedded in the body, and a receiving device installed outside the body receives the oscillation signal.When the bladder stretches to a predetermined state, Configure to activate alarms or other notification mechanisms.

In addition, as another means for detecting the amount of ice storage, a reed switch and a small permanent magnet are placed opposite to the bladder wall, and a compensation current is passed through the outer periphery of the reed switch to control the strength of the magnet's magnetic field using the magnetic field generated by this. Then turn the reed switch 0N.
It is also possible to arbitrarily set the -OFF operating point and operate the reed switch to activate an alarm or other notification mechanism when the bladder expansion reaches a predetermined state.

Next, when a predetermined amount of urine storage is detected in this way,
As a means for confirming the patient's condition and urinating, a conventionally known electrical stimulation method for the bladder wall is employed.

In this case, it is necessary to sew at least one pair of stimulation electrodes consisting of a positive electrode and a negative electrode to the bladder wall, but if the leakage current is large due to the structure and arrangement of the electrodes, the urethral sphincter will contract, causing intravesical pressure. This causes a problem in which urination is interrupted despite the increase in urination.

Therefore, in the present invention, it has been found that it is suitable to use one or more pairs of convex disk-shaped electrodes in order to improve the adhesion to the bladder wall.

Therefore, the general object of the present invention is to
To provide a micturition pacemaker configured to automatically detect the amount of stored urine, notify this state when the amount of stored urine exceeds a predetermined value, and then apply electrical stimulation to the bladder to perform urination.

In order to achieve the above object, in the present invention, a urine storage amount detector and a bladder wall stimulation electrode pair are arranged on the bladder wall of a living body, and electrically actuated based on the positional displacement of the urine storage amount detector. A detection circuit that responds, a voltage generation circuit that applies a stimulation voltage to the stimulation electrode pair, and a circuit that inductively supplies power to the detection circuit and the voltage generation circuit, and In a micturition pacemaker that is equipped with an alarm circuit that receives a signal and notifies that a predetermined urine storage volume has been reached, each bladder wall stimulation electrode pair has a circular convex conductive plate on one side of an insulating support. It becomes fixed,
A feature of the present invention is that the pair of electrodes configured in this manner are held at different polar potentials and a pulse voltage is applied as a stimulation voltage.

In the above-mentioned urinary pacemaker, the urine storage amount detector consists of a pair of disc-shaped electrode plates, one of which is composed of a concentric disc and an annular plate, each of which is held at the same potential, and the other electrode plate is are held at different polar potentials, and the distance displacement between these electrodes can be converted into an electrical resistance change as a function of the amount of urine stored, and can be continuously detected.

In addition, the urine storage amount detector consists of a combination of a reed switch and a permanent magnet, and a coil that supplies a compensation current is wrapped around the outer circumference of the reed switch. 0N-O of the reed switch
By configuring to perform the FF operation, a predetermined amount of stored urine can be detected.

The bladder wall stimulation electrode achieves effective bladder contraction by fixing a circular convex conductive plate to one side of an insulating support and holding each plate at different polar potentials, which are placed facing the bladder wall. be able to.

In this case, it is preferable to apply a pulse voltage to the bladder wall stimulation electrode pair.

Furthermore, when applying the stimulation voltage to the bladder wall stimulation electrode pair, it is preferable to apply the stimulation voltage to the bladder wall stimulation electrode pair by operating a switch.

Next, preferred embodiments of the urinary pacemaker according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a system diagram of a device installed inside the body used in the present invention, which is configured to be able to communicate with a transmitter/receiver installed outside the body, and reference numeral 10 denotes an induction coil for transmitting and receiving radio waves; 12 is a tuning circuit that tunes the radio waves received by the coil 10; 14 is a rectifier circuit; 16 is a waveform shaping circuit; 20 is a stimulation electrode;
0 is attached to the bladder wall at a suitable location by means such as sewing, as described below.

In addition, a urine storage amount detector 22 is attached to a suitable location on the bladder wall, and the displacement of this detector 22 is converted into a time constant displacement (oscillation frequency displacement) of the current charging/discharging circuit (oscillator) 18, and the obtained signal is sent to the coil. 10 to a transmitter/receiver installed outside the body.

Next, a specific example of the urine storage amount detector 22 will be explained.

Taking advantage of the fact that the bladder wall stretches as the amount of urine stored increases, electrodes are attached to the opposite side walls of the bladder, and changes in the distance between the electrodes due to the increase in the amount of urine stored are electrically measured as changes in the resistance between the electrodes. By measuring, the amount of urine stored can be measured continuously.

Therefore, Figure 2a. In the embodiment shown in b, a pair of electrodes 2
4 and 26 are each configured in a disk shape.

In this case, for one electrode 24, the spread of electric lines of force at the electrode end becomes large (especially when d > r, d: inter-electrode distance, r: radius of electrode plate), and the inter-electrode resistance becomes significantly small. Therefore, by combining the concentric annular electrodes 24a and holding them at the same potential, it is possible to prevent the lines of electric force from spreading and easily obtain an inter-electrode resistance value R that is proportional to the inter-electrode distance d.

Therefore, in this embodiment, the electrodes 24 and 26 constructed as described above are arranged symmetrically on the bladder wall 30, with two pairs of electrodes 24 and 26 facing each other, as shown in FIG.

In this case, one electrode 24 is a positive electrode, and the other electrode 24 is a positive electrode.
6 is used as a negative electrode, and it is preferable to fix the electrodes by sewing, etc., respectively.

The electrodes 24 and 26 arranged in this way are connected and arranged as a resistance part R2 of a known RC oscillation circuit (see FIG. 5),
The oscillation frequency ω changes in proportion to the change in the inter-electrode resistance value R2 obtained as a function of the distance d between the electrodes 24 and 26.

Therefore, the relationship between the interelectrode resistance R2 and the oscillation frequency ω in this case is illustrated in FIG. 5.

In this way, the signal whose oscillation frequency changes is transmitted from the internal oscillation unit (induction coil 10) to the outside of the body, and is received by an external device (described later) and converted to and displayed as the amount of urine stored in the bladder. Quantities can be measured and detected continuously.

As another embodiment of the means for measuring the amount of urine stored in the bladder, as shown in FIG. 6, a reed switch 32 and a permanent magnet 34 are used, and a coil 33 is wound around the outer circumference of the reed switch 32. The reed switch 32 and the permanent magnet 34 are arranged to face each other on the bladder wall 30, so that a compensation current (2) is passed through the coil 33.

In this way, the reed switch 32 and the permanent magnet 3
4 reaches a predetermined position, the ON or OFF operation of the O-reed switch 32 is performed, and a predetermined amount of urine stored can be detected.

Therefore, in this case, by variably adjusting the compensation current ■, the distance d between the reed switch 32 and the permanent magnet 34 is
The ON-OFF operating point of the reed switch 32 can be adjusted arbitrarily, and thereby the set value of the urine storage amount can be adjusted as appropriate (see FIG. 7).

Note that both the compensation current and the detection current of the reed switch 32 are supplied from outside the body via the induction coil 10.

Next, a specific example of the stimulation electrode 20 that electrically stimulates the bladder wall 30 to cause the bladder wall 30 to contract and urinate will be described.

FIG. 8 shows an embodiment of the stimulation electrode 20 used in the present invention, in which a conductive electrode plate 36 is connected to an insulating support 3.
The electrode plate 36 has a convex shape to improve adhesion to the bladder wall 30, and a disk shape to prevent leakage current.

Further, a hole 40 for sewing is appropriately provided in a part of the support body 38 at the peripheral edge of the electrode plate 30.

Note that the electrode plate 36 is made of platinum or a platinum material, and the insulating support 38 is preferably made of a polymeric material with little biological reaction, such as medical epoxy resin.

When attaching the stimulation electrode 20 configured in this way to the bladder wall 30, for example, as shown in FIG. 9, two positive electrodes 20a are attached to the ureterovesical junction.

20b, respectively, and these positive electrodes 20a.

The positive electrode 20 is attached to the opposite wall surface of the bladder wall to which the positive electrode 20b is attached.
Two negative electrodes 20c and 20d are attached so as to correspond to electrodes a and 20b and are located diagonally upward by about 2 cm.

By passing a stimulating current between the negative and positive electrodes arranged in this manner, the bladder wall 30 contracts, and the urine in the bladder is urinated through the urethra 42.

As a clinical result, the diameter of the electrode plate was set to 8mm, and the output between the electrodes was 1.2 to 5mm. OV, pulse width 4.6-9.3m sec
, a pulse voltage with a pulse repetition period of 13 to 30 pp, s is suitable, and it was confirmed that in this case there is almost no interruption of urination or delay in urinary flow due to contraction of the urethral sphincter.

Note that the configuration of the stimulation electrode and its attachment position to the bladder wall are not uniformly determined, and it is desirable to perform the design under optimal conditions by appropriately changing the design depending on the patient's symptoms and the like.

An example of an external device for controlling an internal device configured using the urine storage amount detector 22 and the bladder stimulating electrode 20 described above outside the body will be described with reference to FIG. 10.

First, when detecting the amount of urine stored, the power supply section 50 is connected to the carrier wave generation circuit 54 by operating the amount detection switch 52 of stored urine, and operates the carrier wave generation circuit 54 to generate a signal. Power amplifier circuit 56, tuning circuit 58
The signal is transmitted from the induction coil 60 outside the body to the induction coil 10 inside the body.

The signal received by the induction coil 10 is applied to the urine storage amount detector 22 to continuously or discontinuously detect the amount of urine stored in the bladder, and the detection signal is transmitted from the oscillator 24 to the body via the internal induction coil 10. is sent to the external induction coil 60 (see FIG. 1),
The stored urine amount detection signal received by the induction coil 60 operates the alarm circuit 64 via the discrimination circuit 62 (only in the case of continuous measurement).

In this way, the patient can sense that the amount of urine stored in the bladder has reached the set amount by flashing an indicator lamp or activating an alarm outside the body.

Next, operate the stimulation signal generation switch 66 to turn on the power supply section 5.
0 is connected to the carrier wave generation circuit 54 (via the pulse repetition period determination circuit 68 and the pulse width determination circuit 70) to generate a voltage signal having a predetermined pulse width and pulse repetition period, and this stimulation voltage signal is applied to a power amplifier. 56 and a tuning circuit 58, the signal is transmitted from the external induction coil 60 to the internal induction coil 10.

The signal transmitted to the induction coil 10 passes through a tuning circuit 12, a rectifier circuit 14, and a waveform shaping circuit 16, and is applied between a pair of stimulation electrodes 20 to stimulate the bladder wall 30 (see FIG. 1).

As a result, the bladder wall 30 contracts and urinates.

In this way, when the patient senses the alarm signal of the amount of urine stored in the bladder, the patient goes to a predetermined location and presses the stimulation signal generation switch 66.
By manipulating the urination can be achieved.

Therefore, it is preferable that the external device be compact and convenient to carry.

According to the urinary pacemaker of the present invention, the amount of urine stored can be automatically detected, and when the amount of stored urine reaches a predetermined amount, this state can be immediately notified, and the patient can sense this state. The patient can apply electrical stimulation to the bladder through his own operations to achieve smooth urination.

Further, according to the present invention, the urine storage amount detector and the bladder stimulation electrode can be easily attached to the bladder wall, and the power for operating them can be easily supplied by being induced by an external device. Therefore, it is possible to obtain a compact, safe, properly operating urinary pacemaker that is convenient to carry.

Although the preferred embodiments of the present invention have been described above, it goes without saying that various design changes can be made without departing from the spirit of the present invention.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing an example of an internal device of a urinary pacemaker according to the present invention, FIG. 2 shows electrodes constituting a urine storage amount detector used in the present invention, and FIG. 2a is a perspective view; Figure 2 is a sectional view, Figure 3 is an explanatory diagram showing how the electrode shown in Figure 2 is attached to the bladder wall, Figure 4 is an oscillation circuit diagram in which the electrode shown in Figure 2 is inserted as a variable resistor, Fig. 5 is a characteristic curve of the oscillation frequency based on the change in interelectrode resistance obtained in the oscillation circuit shown in Fig. 4, Fig. 6 is a schematic diagram of the configuration of another embodiment of the urine storage amount detector, and Fig. 7 is a diagram showing the structure of another embodiment of the urine storage amount detector. Fig. 6 shows the characteristic curve of the urine storage amount detector, Fig. 8 shows the stimulation electrode used in the present invention, Fig. 8a is a front view, Fig. 8 is a side sectional view, and Fig. 9 is a diagram showing the stimulation electrode used in the present invention. FIG. 10 is an explanatory view showing the state in which the stimulation electrode is attached to the bladder wall, and FIG. 10 is a system diagram showing an example of the external device of the urinary pacemaker according to the present invention. 10... Induction coil, 12... Tuning circuit, 14... Rectifier circuit, 16... Waveform shaping circuit, 1B... Oscillator, 20...
Stimulation electrode, 22... Urine storage amount detector, 24.2
6...electrode, 30...bladder wall, 32...
...Reed switch, 33...Coil,
34... Permanent magnet, 36... Conductive electrode plate, 38... Insulating support, 40...
- Hole, 42... Urethra, 50... Power supply section, 52... Urine storage amount detection switch, 54...
...Carrier wave generation circuit, 56...Power amplifier circuit,
58... Tuning circuit, 60... Induction coil, 62... Discrimination circuit, 64... Alarm circuit, 66... Stimulus signal generation switch, 68・
...Pulse repetition period determination circuit, 70...
・Pulse width determination circuit.

Claims (1)

[Scope of Claims] 1. A detection circuit that arranges a urine storage amount detector and a bladder wall stimulation electrode pair on the bladder wall of a living body and responds electrically based on the positional displacement of the urine storage amount detector; A voltage generation circuit that applies a stimulation voltage to the stimulation electrode pair is provided, and a circuit that inductively supplies power to the detection circuit and the voltage generation circuit is provided, and a circuit that receives a detection signal generated by the detection circuit and generates a predetermined signal. A micturition pacemaker is equipped with an alarm circuit to notify when the amount of urine stored has been reached (in this case, each pair of electrodes for stimulating the bladder wall has a circular convex conductive plate fixed to one side of an insulating support). A micturition pacemaker is characterized in that the pair of electrodes intercepted in this way are held at different polar potentials and are intercepted so that a pulse voltage is applied as a stimulation voltage.2 The urine storage amount detector is a pair of circles. Consisting of plate-shaped electrodes, one electrode plate is composed of a concentric circular disk and an annular plate, each holding the same potential G (while the other electrode plate is held at a different potential, and the distance displacement between these electrodes is calculated as urine storage. The urinary pacemaker according to claim 1, which continuously detects the change in electrical resistance as a function of the amount. 3. The urine storage amount detector is composed of a combination of a reed switch and a permanent magnet, A coil that supplies a compensation current is wound around the outer circumference of the reed switch, and when the separation distance between the reed switch and the permanent magnet reaches a predetermined state, the reed switch is set to 0N-OF.
The urinary pacemaker according to claim 1, which detects the amount of urine stored by performing the F operation.