JPH0257416B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to the structure of a sensor that is implanted inside a living body to observe its temperature, pressure, etc. and wirelessly transmit the information outside the living body.

(Prior Art) In recent years, temperature therapy for cancer has attracted attention, and an implantable temperature sensor has been proposed for measuring the temperature of cancerous fibrils to be heated and normal fibrils surrounding them.
There is also a demand for a similar pressure sensor for measuring pressure in various parts of the brain or abdominal cavity.

Such in-vivo implantable sensors generally combine a piezoelectric vibrator, such as a crystal, whose resonant frequency changes depending on temperature or pressure, and an antenna coil. The point where energy absorption is maximum when this frequency matches the resonant frequency of the piezoelectric vibrator at a specific temperature is detected using an in vitro measuring instrument. The dip method or a method of observing the reverberation of the piezoelectric vibrator when the supply of electromagnetic waves from outside the body is temporarily stopped to the piezoelectric vibrator vibrating at a resonant frequency has been proposed. The outer shape of each of them was either cylindrical or elongated rod-like for the purpose of locating the antenna coil near the surface of the living body and improving the reception sensitivity of temperature information.

However, if such a sensor is simply implanted inside a living body, the living body itself and its interior are constantly active, so the sensor will move over time, making it impossible to measure the temperature or pressure at the desired location. There was a flaw.

(Object of the Invention) The present invention has been made in order to eliminate the defects of the conventional in-vivo implantable sensors as described above. An object of the present invention is to provide an in-vivo implantable sensor provided with a locking tool that is secured to the body and prevented from moving.

(Summary of the Invention) In order to achieve the above-mentioned object, a sensor according to the present invention is provided with a thread through-hole or the like for connecting the sensor to a muscle or the like on its surface.

(Example) Hereinafter, the present invention will be described in detail based on an example shown in the drawings.

FIG. 2 is a sectional view showing the structure of an in-vivo temperature sensor to which the present invention is applied.

That is, a small crystal resonator 1 is sealed in a metal case 2 and used as a temperature sensing element, and an antenna coil 3 is sealed in a plastic case 4, and both are made of metal or plastic of the required length. The vibrator 1 and the antenna coil 3 are connected by a tube 5, and a cord 6 is disposed within the tube 5 to connect the vibrator 1 and the antenna coil 3, and the whole is coated with a silicone resin or the like 7 that is compatible with living tissue.

If a sensor having such a structure is simply buried in a living body, the sensor moves within the living body over time, causing the crystal oscillator 1, which is a temperature sensing element, to deviate from the desired temperature measurement position, making accurate temperature measurement impossible. As mentioned above.

In order to solve this problem, the sensor according to the present invention has the following configuration.

That is, as shown in Fig. 1a, small protrusions 9, 9 are provided at appropriate positions on the outer periphery of the sensor body 2, and small holes 10, 10 for threading the thread are bored in these, or as shown in Fig. Rods 11, 11 are erected on the surface of the main body 2.

By doing this, the living body is incised and the sensor 8 is inserted.
When embedding the sensor, if the sensor is connected to an appropriate position in the nearby muscle using the small holes 10, 10, . This can be prevented. In this case, external silk thread may be used for binding.

By the way, the temperature sensor shown in FIG. 2 does not necessarily need to be implanted through an incision in the living body. For example, in early stage cancer, the cancer fibrils are still small and their number is limited, so a needle-like tubule (called an applicator) is inserted from the living body surface toward the cancer fibrils, and the sensor is passed through this tube to the cancer fibrils. It is conceivable that it comes into contact with the In such a case, the above-mentioned Figure 1a
Or, it is extremely inconvenient for a protrusion as shown in b to exist on the sensor surface.

Therefore, as shown in FIG. 1C, annular recesses 12, 12, .

Further, as shown in FIG. d, small holes 14, 14, . . . may be provided passing through the sensor body 8 at appropriate locations. In this case, for example, as shown in the enlarged view in the same figure, the through hole 1
A suitable plastic block 13 with 4 holes drilled in it.
A conducting wire 6 connecting the sensor body through the hole 1 and connecting the vibrator 1 and the antenna coil 3 is connected to the sensor body through the hole 1.
It is sufficient if the block 13 is penetrated so as to avoid 4.

By doing so, the sensor according to the present invention can be commonly used both when incising a living body and implanting it, and when inserting it using an applicator. That's convenient.

Although the present invention has been described above by exemplifying a temperature sensor, the present invention is not necessarily limited to this and can be similarly applied to a pressure sensor implantable in a living body, and in that case, the temperature sensing element can be used to obtain pressure or other information. It will be understood that what is necessary is to replace the information with an appropriate sensor that senses the information.

In the examples, a passive sensor was used to simplify the explanation, but there is no reason to believe that the present invention applies only to passive sensors. It is not necessary to explain that the present invention is also applicable to type sensors.

(Effects of the Invention) Since the present invention is constructed as described above, it is possible to prevent movement of the observation point of an implantable sensor that measures temperature, pressure, etc. inside a living body, so it is possible to prevent the observation point of an implantable sensor that measures temperature, pressure, etc. If used to measure the internal body temperature during thermotherapy for cancer, which must be kept in check, it will be possible to accurately measure the temperature of cancer cells and their surroundings, thereby preventing accidental burns to normal cells. It is extremely effective in preventing accidents.

[Brief explanation of drawings]

FIGS. 1a, b, c, and d are views showing different configurations of the temperature sensor according to the present invention, and FIG. 2 is a sectional view showing the structure of a conventional temperature sensor. 8...Sensor body, 9, 11, 12 and 14...
...Lockers, 10, 12 and 14...Small holes.

Claims (1)

[Claims] 1. In a sensor that is implanted in a living body for a long period of time to observe the temperature, pressure, etc. of that part, a thread locking device is provided at an appropriate place on the surface of the sensor, so that the living body can be monitored. An in-vivo implantable sensor equipped with a locking tool, characterized in that when an incision is made and the sensor is implanted, the sensor is locked and fixed at a proper location such as a muscle within the living body using a thread. 2. Claim 1, characterized in that the locking device is a protruding piece or a protruding rod provided at an appropriate position on the sensor surface and provided with a small hole for thread penetration or a protruding portion for locking.
An in-vivo implantable sensor comprising the described locking device. 3. Claim 1, wherein the locking device is an annular recess provided at a proper location on the outer circumference of the sensor.
An in-vivo implantable sensor provided with the described locking device. 4. The in-vivo implantable sensor provided with a locking device according to claim 1, wherein the locking device is a waterproof small hole that penetrates through the sensor main body at an appropriate location.