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CN-121985916-A - Laser irradiation system, laser control device, and laser irradiation method

CN121985916ACN 121985916 ACN121985916 ACN 121985916ACN-121985916-A

Abstract

A laser irradiation system (1) for irradiating a stone (S) existing in a body with laser light to break the stone (S) in a liquid, wherein the laser irradiation system (1) comprises a laser fiber (3) having a fiber emitting end (3 a) for emitting the laser light, and at least one processor for controlling the frequency of the laser light emitted from the fiber emitting end (3 a), the processor switching the frequency of the laser light between a first pulse group having a high frequency of an output power for breaking the stone (S) and a second pulse group having a frequency lower than the first pulse group and a waveform in which the peak power gradually increases in the axial direction of the irradiation time, and emitting the second pulse group at least one of before and after the timing of emitting the first pulse group.

Inventors

  • Lin Tuohai

Assignees

  • 奥林巴斯株式会社

Dates

Publication Date
20260505
Application Date
20231201

Claims (20)

  1. 1. A laser irradiation system for fragmenting stones present in a body of a liquid by irradiating laser light to the stones, comprising: a laser fiber having a fiber emitting end for emitting the laser light, and At least one processor for controlling the frequency of the laser light emitted from the optical fiber emitting end, The processor switches the frequency of the laser beam between a first pulse group, which is a pulse group having a high frequency of an output power for breaking up the stones, and a second pulse group, which is a pulse group having a waveform having a frequency lower than the first pulse group and having a peak power gradually increasing in an axial direction of an irradiation time, and emits the second pulse group at least one of before and after a timing of emitting the first pulse group.
  2. 2. The laser irradiation system according to claim 1, wherein the waveform of the first pulse group is a multi-pulse sequence.
  3. 3. The laser irradiation system according to claim 1 or 2, wherein the waveform of the second pulse group is a triangular waveform in which peak power gradually increases in the axial direction, or an M-shaped waveform in which peak power gradually decreases in the axial direction and then gradually increases.
  4. 4. The laser irradiation system according to claim 1, wherein the processor executes a plurality of pulse groups, and a stop period for stopping the emission of the laser light for a predetermined period is provided after an emission period constituted by the emission period of the first pulse group and the emission period of the second pulse group in the pulse groups.
  5. 5. The laser irradiation system according to claim 4, wherein the processor determines the power of the first pulse group, the power of the second pulse group, and the length of the stop period within a range in which the average power of the laser light emitted from the pulse group is 20W or less.
  6. 6. The laser irradiation system according to claim 5, wherein the average power is calculated by the following formulas (1), (2) and (3), [ Number 1] ...(1) [ Number 2] ...(2) [ Number 3] ...(3) P ave is the average power, PE A and PE H are pulse energy, f A and f H are frequency, N A and N H are pulse number, and T int is the off period.
  7. 7. The laser irradiation system according to any one of claims 4 to 6, wherein the processor is configured to execute, next to a first one of the pulse groups, a second pulse group in which the stop period is provided after an emission period constituted by an emission period of a third pulse group which is a pulse group having an output power for breaking up the stones and having a high frequency different from that of the first pulse group, and an emission period of a fourth pulse group which is a pulse group having a frequency different from that of the second pulse group and lower than that of the third pulse group and in which a peak power gradually increases in an axial direction of an irradiation time.
  8. 8. The laser irradiation system according to claim 1, comprising an endoscope insertable into the body, The endoscope includes a channel through which the laser fiber passes and the fiber outlet end can protrude forward.
  9. 9. A laser control device is characterized by comprising at least one processor which controls the frequency of laser light emitted from the optical fiber emitting end of a laser optical fiber toward stones existing in a body, The processor switches the frequency of the laser beam between a first pulse group, which is a pulse group having a high frequency of an output power for breaking up the stones, and a second pulse group, which is a pulse group having a waveform having a frequency lower than the first pulse group and having a peak power gradually increasing in an axial direction of an irradiation time, and emits the second pulse group at least one of before and after a timing of emitting the first pulse group.
  10. 10. The laser control apparatus of claim 9, wherein the waveform of the first pulse group is a multi-pulse sequence.
  11. 11. The laser control apparatus according to claim 9 or 10, wherein the waveform of the second pulse group is a triangular waveform in which peak power gradually increases in the axial direction, or an M-shaped waveform in which peak power gradually decreases in the axial direction and then gradually increases.
  12. 12. The laser control apparatus according to claim 9, wherein the processor executes a plurality of pulse groups, and a stop period for stopping the emission of the laser light for a predetermined period is provided after an emission period constituted by the emission period of the first pulse group and the emission period of the second pulse group in the pulse groups.
  13. 13. The laser control apparatus according to claim 12, wherein the processor determines the power of the first pulse group, the power of the second pulse group, and the length of the stop period within a range in which the average power of the laser light emitted from the pulse group is 20W or less.
  14. 14. The laser control apparatus according to claim 13, wherein the average power is calculated by the following formulas (1), (2) and (3), [ Number 1] ...(1) [ Number 2] ...(2) [ Number 3] ...(3) P ave is the average power, PE A and PE H are pulse energy, f A and f H are frequency, N A and N H are pulse number, and T int is the off period.
  15. 15. The laser control apparatus according to any one of claims 12 to 14, wherein the processor is configured to execute, next to a first one of the pulse groups, a second pulse group in which the stop period is provided after an emission period constituted by an emission period of a third pulse group which is a pulse group having an output power for breaking up stones and having a high frequency different from that of the first pulse group, and an emission period of a fourth pulse group which is a pulse group having a frequency different from that of the second pulse group and lower than that of the third pulse group and in which a peak power gradually increases in an axial direction of an irradiation time.
  16. 16. A laser irradiation method for breaking up stones in a liquid by irradiating laser light to the stones present in the body, characterized in that, A first pulse group having a high frequency of output power for breaking up the stones is emitted from an optical fiber emitting end toward the stones, And a second pulse group having a waveform with a lower frequency than the first pulse group and a peak power gradually increasing in the axial direction of the irradiation time is emitted at least before and after the timing of emitting the first pulse group.
  17. 17. The laser irradiation method according to claim 16, wherein a pulse group in which a stop period for stopping the emission of the laser light for a certain period is provided after an emission period constituted by the emission period of the first pulse group and the emission period of the second pulse group is implemented.
  18. 18. The laser irradiation method according to claim 17, wherein the power of the first pulse group, the power of the second pulse group, and the length of the stop period are determined so that the average power of the laser light emitted from the pulse group is 20W or less.
  19. 19. The laser irradiation method according to claim 18, wherein the average power is calculated by the following formulas (1), (2) and (3), [ Number 1] ...(1) [ Number 2] ...(2) [ Number 3] ...(3) P ave is the average power, PE A and PE H are pulse energy, f A and f H are frequency, N A and N H are pulse number, and T int is the off period.
  20. 20. The laser irradiation method according to any one of claims 17 to 19, wherein a second pulse group in which the stop period is provided after an emission period constituted by an emission period of a third pulse group having an output power for breaking up the stones and having a high frequency different from that of the first pulse group and an emission period of a fourth pulse group having a waveform having a frequency different from that of the second pulse group and lower than that of the third pulse group and having a peak power gradually increasing in an axial direction of an irradiation time is performed next to the first pulse group.

Description

Laser irradiation system, laser control device, and laser irradiation method Technical Field The present invention relates to a laser irradiation system, a laser control device, and a laser irradiation method. Background Conventionally, a technique for breaking stones in the kidney by laser light is known (for example, refer to patent document 1). The stones are crushed to a desired size by laser irradiation from a stage (crushing, powdering) of large stones to a stage (popcorn dusting, powdering of popcorn) of flying stones which are reduced by crushing. The technique described in patent document 1 changes the frequency of laser light as one of the deformations of the crushed stones by laser light irradiation. [ Prior Art literature ] [ Patent literature ] Patent document 1 International publication No. 2020/033121 Disclosure of Invention [ Problem to be solved by the invention ] However, in patent document 1, although increasing the amount of broken stones and suppressing the scattering of stones are considered, nothing is mentioned about suppressing ineffective irradiation of laser light. Strong water flow is generated under the irradiation of high-power laser, so that the calculus flies under the condition that the calculus cannot be crushed at one time by high power, thereby leading to ineffective irradiation of the laser. When ineffective irradiation of the laser light occurs, the input energy increases accordingly, resulting in an increase in the temperature in the kidney of the patient. The present invention has been made in view of the above circumstances, and an object thereof is to provide a laser irradiation system, a laser control device, and a laser irradiation method that can reduce ineffective irradiation of laser light and achieve reduction of operation time. [ Means of solving the problems ] To achieve the above object, the present invention provides the following means. The first aspect of the present invention is a laser irradiation system for fragmenting stones in a liquid by irradiating the stones present in the body with laser light, the laser irradiation system including a laser fiber having a fiber emitting end from which the laser light is emitted, and at least one processor for controlling a frequency of the laser light emitted from the fiber emitting end, the processor switching the frequency of the laser light between a first pulse group and a second pulse group, the first pulse group being a pulse group having a high frequency of an output power for fragmenting the stones, the second pulse group being a pulse group having a lower frequency than the first pulse group and a waveform having a peak power gradually increasing in an axial direction of an irradiation time, the second pulse group being emitted at least one of before and after a timing of emitting the first pulse group. According to this aspect, the laser light of the first pulse group has high breaking capacity, but easily scatters stones. On the other hand, although the laser beam of the second pulse group has low breaking power, the pumping effect of pulling back the stone to the optical fiber emitting end within a certain range from the optical fiber emitting end is high. In particular, the laser light of the second pulse group has a waveform having a peak power gradually increasing in the axial direction of the irradiation time, and thus has a higher pumping effect than the case of a waveform having a rectangular wave. Therefore, the processor emits the laser beam of the first pulse group and the laser beam of the second pulse group in the front and back directions at the timing, so that the crushing effect caused by the laser beam of the first pulse group and the pumping effect caused by the laser beam of the second pulse group can compensate for the respective disadvantages, and the crushing efficiency can be improved. Thus, ineffective irradiation of laser light for emitting laser light in a state in which stones are disposed at positions distant from the optical fiber emitting end can be suppressed, and the operation time can be shortened. In the laser irradiation system according to the above aspect, the waveform of the first pulse group may be a multi-pulse sequence. With this configuration, the laser light of the first pulse group of the knot Dan Zhaoshe can be concentrated in a short time before the stone is scattered. In the laser irradiation system according to the above aspect, the waveform of the second pulse group may be a triangular waveform in which the peak power gradually increases in the axial direction, or an M-shaped waveform in which the peak power gradually decreases in the axial direction and then gradually increases. With this configuration, when the second pulse train has a triangular waveform, a plurality of bubbles are continuously generated from the tip of the optical fiber, and then the bubbles adjacent to each other are combined, thereby forming snowman-shaped block-shaped bubbles. The