JPS5949778A - Laser irradiation apparatus for treating birthmark - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus utilizing the second harmonic of an N(1:YAG laser).

BACKGROUND ART Conventionally, a birthmark treatment method using a continuous wave beam of an argon laser has been known. This method is a treatment method that selectively cauterizes and ruptures the affected area by irradiating the affected area with a high-power argon laser beam.

However, the treatment of bruises using the continuous wave beam of the Alcon laser has the following problems.

(1) The wavelength of the argon laser, which has low efficiency, is 5,145^, but the absorption wavelength of blood, which selectively absorbs the laser beam, has a peak at 5.42 OA as shown in Figure 1. The wavelength is 11 degrees off from this peak.For this reason, the efficiency of argon lasers used for bruise treatment is extremely low.

(2) Damage to normal cells Since continuous wave beams are not used, damage to normal cells due to thermal diffusion is unavoidable.

In order to solve the above problem (1), the present inventors proposed converting the wavelength of the argon laser to yB fM, which is the maximum absorption wavelength of blood, in Japanese Patent Application Laid-Open No. 1407-1407. Although this proposal has made it possible to efficiently treat n', the device proposed above is capable of treating wavelengths: μ, ・Ki/. It was expensive and had problems as a practical device. Also, problem (2)
were not resolved by the above proposal and remained in place.

In order to solve the above problem, the present inventors first thoroughly investigated a laser device having a conversion wavelength near the maximum absorption wavelength of blood, and found that the second harmonic of the Nd:YAG laser is s, 5ooi. They found that this wavelength is extremely close to the maximum absorption wavelength of blood, 5,420X, and that wavelength conversion is easy. Furthermore, using the second harmonic of the Nd:YAG laser, The present invention was arrived at as a result of extensive research to provide a device that does not cause any scratches. That is, the present invention repeatedly Q-switches N
d A second subharmonic wave is generated from the pulsed beam of the CYAG laser, and this second harmonic wave is separated from the fundamental wave, and the separated second harmonic wave is attached to the tip of an optical fiber. The novel idea of the present invention is that the second high r of the Nd:YAt+ laser has a wavelength extremely close to the maximum absorption wavelength of blood;
This is due to the use of VIl waves. This right leg made it possible to selectively absorb the laser beam into red blood cells, making it possible to perform highly efficient treatment.

Another novel idea of the present invention is Nil: 'YAOY
The reason is that the AG laser-like beam was irradiated onto the affected area.

With this idea, the positive 7iff around the affected area is 41! It has become possible to prevent thermal damage to I cells.

Next, an embodiment of the apparatus of the present invention will be explained using drawing C.

Figure 1 is a block diagram of the device of the present invention.
, a Q switch 2 that converts the continuous wave laser beam oscillated by this device n into repetitive oscillation heat, and a Q switch 2 that converts the continuous wave laser beam oscillated by this device n into a repetitive oscillation heat, and a
．． A crystal 6 for generating a second harmonic such as iJ:' K11)P which generates a 4'r 2ft'jH harmonic of 30Ok, and a fundamental wave a and a second harmonic emitted from the crystal. Wave b 4 - A demultiplexing device 4 such as a diffraction grating or prism for demultiplexing, and the demultiplexed second sieve 4+, IiI wave I) are collected and sent to the core of the glass fiber for j9 light. Condensing lens 5 and s” for efficient laser beam incidence
＃”g It is composed of a glass fiber 6 for guiding the complaint wave to the affected area, and a laser gun 8 housing a lens 7 for adjusting the laser beam emitted from the glass fiber to an appropriate beam diameter. 9 is a light guide. This is a holder for fixing the end of a glass fiber.

Such a device uses a pulsed second harmonic emitted from a Nd:YAG laser, and the pulse width of this pulse is typically less than 1 microsecond in a Q-switch. For bruise treatment, the smaller the pulse width, the better.This is an example in which guns 5 to 7 are attached to a traveling device.This device is equipped with a laser gun 8 attached to the tip of a glass fiber 6 that guides Hahalus-shaped m2A harmonics. The moving table 10 (
The apparatus is composed of an X-Y table (hereinafter referred to as an X-Y table), a support table 11 on which this moving table is mounted, and an illumination device 12 for operating the X-Y table 1o and laser irradiation.

Reference numeral 13 denotes a remote control switch for remotely controlling the control device. The support stand 11 has an idI-shaped vertical support 15 fixed in the pipe 14, an ijJ moving body 16 which is arranged to be able to rise and fall along this axis 15, and this ijJ moving body 1.
6, a horizontal member 1 is supported so as to be slidable in the front and back direction.
7, tt+1 is formed, and the front end of this horizontal member 17 is provided with an X-Y
A table 10 is already attached. A pulley 19 is attached to the upper end of the vertical shaft 15, the movable body 16 is held at one end of a wire 20 suspended from the pulley 19, and a weight 21 for balance is attached at the other end. is installed. Reference numeral 22 denotes a locking member that is screwed onto the movable body 16 and fixes the movable body in a predetermined position. Horizontal member 1
7 is slidably supported by a bearing provided in the movable body 16 in the thrust direction. X-Y two-pull 10
Y table 2 movably attached to base 2
6, this Y table +, ls, fl 7C base, and on this base, an The above X and Y tables are operated by a step motor 25,
It moves forward and backward as well as left and right by the rotation of the screw rod that receives the rotational force of 26. This XX table can have various known structures.

Reference numeral 27 denotes a bracket fixed to the X table and loaded forward, and a laser gun holding part 28 is fixed to the tip of this bracket, and a laser gaff 8 is attached to this part.

The above device first adjusts the horizontal member 17 constituting the support base 11 and positions it near the affected area S to be treated of the patient M on the X-Y table IGi bed 50 attached to one end of this member, Furthermore, after setting the distance between the tip of the rail gun I3 and the affected area S to 5 to 60 degrees, treatment is performed by manually or automatically irradiating the laser beam onto the affected area.

As described above, the device of the present invention can perform extremely efficient treatment by using the second harmonic of the Nd: YAG laser, and also reduces the heat of normal skin by irradiating the beam of the above-mentioned laser in a pulsed manner. It is a device that is extremely useful in practice, as it can completely prevent damage to targets, and even when using a low-power laser beam, it has a therapeutic effect equal to or greater than that of conventional high-power laser beams.

Example 1 Output approximately 100 mJ 7. Itsuchi N (1: YA
The following experiment was conducted using the second harmonic repetitive oscillation output of the G laser device.

Red pigment was evenly applied to one side of 50μ thick parchment paper (10 sheets were colored with red color, red side up) and artificial birthmarks were made by kneading with nails. The parchment paper layer corresponds to normal skin.

To this artificial birthmark, the wavelength 53007 mB emitted from the above device and the intensity 1=@=fwatt 2nd +! +5 harmonics
It was irradiated twice.

As a result, the red pigment in the six layers of parchment paper decomposed, and when observed under a microscope at 400x magnification, it was found that no trace remained (A).On the other hand, the parchment paper layer was not damaged at all.

The above results demonstrate that in the treatment of bruises, the bruises can be effectively destroyed and removed without damaging normal tissues.

Comparative Example Ten sheets of sulfur Teflon paper, the same as in Example 1, were made into artificial bruises using a wheel λ, and the artificial bruises were exposed to a continuous laser beam (
0.2 seconds, 2. ! When irradiated with 5 watts of water, holes with a diameter of about 1.5 mm were formed over 6 layers.

The above results indicate that continuous laser beam damages secant cells.

[Brief explanation of drawings]

Fig. 1 is a graph showing the absorption wavelength of blood; Fig. 2 is a block diagram showing an embodiment of the device of the present invention; and Fig. 3 is a side view showing an example of the laser traveling device. . 1...Nd:, YAG laser 2...
・・・・Q switch 6 ・・・・Crystal for second harmonic generation 6 ・・・Optical fiber 8・・・・Laser gun 10・・・・Mobile unit patent applicant Designated by the Director of the Agency of Industrial Science and Technology (one idiot) Agent: Agency of Industrial Science and Technology (
Todoroki, director of LI Technology Research Institute 427

Claims (1)

[Claims] 1. Repetitive Q switch Nd: Generates the second harmonic from the pulsed beam of the YAG laser, separates this second harmonic from the crystal main wave, and sends the separated second harmonic to the tip of the optical fiber. 2. The apparatus according to claim 1, wherein the laser gun is mounted on a movable table that moves above the affected area in front, back, right and left directions.