Picosecond laser apparatus and methods for treating target tissues with same

• US 10,581,217 B2
• Filed: 03/25/2019
• Issued: 03/03/2020
• Est. Priority Date: 04/18/2012
• Status: Active Grant

• Current Assignee: Cynosure, LLC (Hologic Incorporated)
• Original Assignee: Cynosure, LLC (Hologic Incorporated)
• Inventors: Sierra, Rafael Armando, Mirkov, Mirko Georgiev
• Primary Examiner(s): Park, Kinam
• Application Number:
  US16/363,597
• Publication Number:
  US 20190221989A1
• Time in Patent Office: 344 Days
• CPC Class Codes: A61B 18/203 applying laser energy to the outside of the body
• CPC Class Codes: A61B 2018/00458 Deeper parts of the skin, e.g. treatment of vascular disorders or port wine stains
• CPC Class Codes: F04C 2270/0421 Controlled or regulated
• CPC Class Codes: H01S 3/0627 the resonator being monolithic, e.g. microlaser
• CPC Class Codes: H01S 3/08054 Passive cavity elements acting on the polarization, e.g. a polarizer for branching or walk-off compensation quarter-wave plates in a Q-switch laser H01S3/1124, H01S3/115
• CPC Class Codes: H01S 3/094038 End pumping
• CPC Class Codes: H01S 3/094076 Pulsed or modulated pumping H01S3/1024 takes precedence
• CPC Class Codes: H01S 3/1024 for pulse generation
• CPC Class Codes: H01S 3/107 using electro-optic devices, e.g. exhibiting Pockels or Kerr effect H01S3/1061, H01S3/1063, H01S3/1065 take precedence
• CPC Class Codes: H01S 3/1075 for optical deflection
• CPC Class Codes: H01S 3/1103 Cavity dumping
• CPC Class Codes: H01S 3/1106 Mode locking
• CPC Class Codes: H01S 3/1109 Active mode locking
• CPC Class Codes: H01S 3/1611 neodymium
• CPC Class Codes: H01S 3/1618 ytterbium
• CPC Class Codes: H01S 3/1623 chromium, e.g. Alexandrite
• CPC Class Codes: H01S 3/1643 YAG
• CPC Class Codes: H01S 3/1673 YVO4 [YVO]

Abstract

Apparatuses and methods are disclosed for applying laser energy having desired pulse characteristics, including a sufficiently short duration and/or a sufficiently high energy for the photomechanical treatment of skin pigmentations and pigmented lesions, both naturally-occurring (e.g., birthmarks), as well as artificial (e.g., tattoos). The laser energy may be generated with an apparatus having a resonator with the capability of switching between a modelocked pulse operating mode and an amplification operating mode. The operating modes are carried out through the application of a time-dependent bias voltage, having waveforms as described herein, to an electro-optical device positioned along the optical axis of the resonator.

Claims

1. A method of treating a target tissue comprising:

generating, using a laser source, an output beam having a subnanosecond pulse duration;

modifying the output beam, using an optical system, to provide a photomechanically disruptive treatment beam;

directing the photomechanically disruptive treatment beam to one or more regions of the target tissue;

photomechanically disrupting the one or more regions of the target tissue; and

inducing collagen restoration within the target tissue in response to photomechanically disrupting the one or more regions of target tissue.

2. The method of claim 1 further comprising rejuvenating the target tissue.

3. The method of claim 2 wherein rejuvenating the target tissue comprises inducing epithelial cell restoration within the target tissue in response to photomechanically disrupting the one or more regions of the target tissue.

4. The method of claim 2 wherein rejuvenating the target tissue comprises increasing amount of collagen disposed therein relative to untreated tissue.

5. The method of claim 1 wherein the photomechanically disruptive treatment beam has a non-uniform beam profile, the non-uniform beam profile comprising a plurality of regions of relatively high energy per unit area dispersed within a substantially uniform background region of relatively low energy per unit area.

6. The method of claim 5 further comprising increasing temperature of a first region of target tissue to a first temperature T1 and increasing or maintaining temperature of a second region of target tissue to a second temperature T2 in response to distribution of regions of relatively high energy and regions of relatively low energy.

7. The method of claim 6 wherein T1 ranges from about 45 degrees Celsius to about 50 degrees Celsius.

8. The method of claim 6 wherein T1 is approximately 70 degrees Celsius or greater.

9. The method of claim 1, wherein the photomechanically disruptive treatment beam has an energy spot diameter of about 5 mm.

10. The method of claim 1, wherein the photomechanically disruptive treatment beam has an energy spot diameter which can be changed according to area of the target tissue.

11. A method of treating a target tissue comprising one or more pigments, the method comprising:

generating, using a laser source, an output beam having a subnanosecond pulse duration;

modifying the output beam, using an optical system, to provide a photomechanically disruptive treatment beam;

directing the photomechanically disruptive treatment beam to one or more pigments of the target tissue, wherein the one or more pigments are visible prior to treatment; and

decreasing visible appearance of one or more pigments within the target tissue in response to the photomechanically disruptive treatment beam.

12. The method of claim 11, wherein the one or more pigments comprise one or more tattoo pigments.

13. The method of claim 11, wherein the target tissue is a pigmented lesion.

14. The method of claim 11 wherein the one or more pigments is melanin.

15. The method of claim 11 wherein decreasing visible appearance of one or more pigments comprises decreasing visible appearance of a pigmented lesion within the target tissue.

16. The method of claim 11, wherein the photomechanically disruptive treatment beam has a non-uniform beam profile, the non-uniform beam profile comprising a plurality of regions of relatively high energy per unit area dispersed within a substantially uniform background region of relatively low energy per unit area.

17. The method of claim 16 further comprising increasing temperature of a first region of target tissue to a first temperature T1 and increasing or maintaining temperature of a second region of target tissue to a second temperature T2 in response to distribution of regions of relatively high energy and regions of relatively low energy.

18. A method of treating tissue comprising oxyhemoglobin, the method comprising:

generating, using a laser source, an output beam having a subnanosecond pulse duration;

modifying the output beam, using an optical system, to provide a photomechanically disruptive treatment beam;

directing the photomechanically disruptive treatment beam to one or more regions of the target tissue comprising oxyhemoglobin, wherein the target tissue comprises a vascular lesion that is visible prior to treatment; and

decreasing visible appearance of the vascular lesion in response to the photomechanically disruptive treatment beam.

19. The method of claim 18, wherein the photomechanically disruptive treatment beam has a non-uniform beam profile, the non-uniform beam profile comprising a plurality of regions of relatively high energy per unit area dispersed within a substantially uniform background region of relatively low energy per unit area.

20. The method of claim 19 further comprising increasing temperature of a first region of target tissue to a first temperature T1 and increasing or maintaining temperature of a second region of target tissue to a second temperature T2 in response to distribution of regions of relatively high energy and regions of relatively low energy.

21. The method of claim 18, wherein the photomechanically disruptive treatment beam has an energy spot diameter of about 5 mm.

22. The method of claim 18, wherein the photomechanically disruptive treatment beam has an energy spot diameter which can be changed according to area of the target tissue.