Selective fat removal using photothermal heating

• US 9,522,289 B2
• Filed: 12/23/2015
• Issued: 12/20/2016
• Est. Priority Date: 05/08/2012
• Status: Active Grant

• Current Assignee: eLux Medical, Inc, Regents of the University of California (University of California)
• Original Assignee: eLux Medical, Inc, Regents of the University of California (University of California)
• Inventors: Almutairi, Adah, Almutairi, Khalid
• Primary Examiner(s): Peffley, Michael
• Assistant Examiner(s): GIULIANI, THOMAS ANTHONY
• Application Number:
  US14/757,872
• Publication Number:
  US 20160236005A1
• Time in Patent Office: 363 Days
• Field of Search: 606/27, 606/33, 607/89, 607/100, 604/20, 604/542
• US Class Current: 1/1
• CPC Class Codes: A61B 18/04 by heating by applying electromagnetic radiation A61B18/18; hyperthermia using electric or magnetic fields, radiation or ultrasound A61N
• CPC Class Codes: A61B 18/203 applying laser energy to the outside of the body
• CPC Class Codes: A61B 2018/00452 Skin
• CPC Class Codes: A61B 2018/00458 Deeper parts of the skin, e.g. treatment of vascular disorders or port wine stains
• CPC Class Codes: A61B 2018/00464 Subcutaneous fat, e.g. liposuction, lipolysis
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00809 measured thermochromatically
• CPC Class Codes: A61K 2800/81 Preparation or application process involves irradiation
• CPC Class Codes: A61K 2800/91 Injection
• CPC Class Codes: A61K 33/242 Gold; Compounds thereof
• CPC Class Codes: A61K 41/0052 Thermotherapy; Hyperthermia; Magnetic induction; Induction heating therapy
• CPC Class Codes: A61K 8/0241 Containing particulates characterized by their shape and/or structure see also A61K8/04, A61K8/11, and A61K8/14, further aspects are classified in A61K2800/40 and subcodes
• CPC Class Codes: A61K 8/19 containing inorganic ingredients
• CPC Class Codes: A61K 9/14 Particulate form, e.g. powders, Processes for size reducing of pure drugs or the resulting products, Pure drug nanoparticles microspheres A61K9/16; microcapsules A61K9/50; nanocapsules, nanoparticles of the matrix type A61K9/51
• CPC Class Codes: A61M 1/892 with treatment of the collected fat
• CPC Class Codes: A61M 2202/08 Lipoids
• CPC Class Codes: A61M 2205/052 infrared
• CPC Class Codes: A61N 2005/0659 infrared
• CPC Class Codes: A61N 5/062 Photodynamic therapy, i.e. excitation of an agent
• CPC Class Codes: A61N 5/067 using laser light
• CPC Class Codes: A61Q 19/06 : for countering cellulitis

Abstract

A system and method are provided for minimally-invasive selective fat removal from a target area by injecting the area with a solution of photo-absorbing nanoparticles and irradiating the injected area with a beam of near infrared (NIR) light. The NIR emission wavelength excites the nanoparticles to melt fat within the target area so that the liquefied fat can be aspirated from the target area. The nanoparticles may be gold nanorods having aspect ratios selected to produce surface plasmon resonance when irradiated with NIR light around 800 nm.

Claims

1. A method for selective removal of fat from a target area in a subject in need thereof, comprising:

injecting a solution of photo-absorbing nanoparticles in a pattern to define a uniform distribution of injected solution in adipose tissue in the target area, wherein the solution comprises gold nanorods suspended in water at a concentration range of 10¹¹ to 10¹³ GNR/mL;

delivering a series of pulses of near infrared light across an area of skin overlying the target area and into the injected solution for an exposure duration to induce surface plasmon resonance in the nanoparticles, wherein the near infrared light has a combination of optical parameters selected from the group consisting of beam energy, pulse duration, emission wavelength within a range of 700 to 900 nm, emission intensity, beam focus and beam area, the optical parameters and the exposure duration selected to excite the nanoparticles to liquefy fat within the target area; and

aspirating a liquid from the target area, the liquid comprising subcutaneous tissue, liquefied fat, and the injected solution.

2. The method of claim 1, wherein the step of delivering comprises scanning the near infrared light across the target area using a plurality of passes.

3. The method of claim 2, further comprises applying a cooling material to the area of skin overlying the target area after a subset of the plurality of passes.

4. The method of claim 1, wherein the emission wavelength is 800 nm±

10 nm.

5. The method of claim 1, wherein the nanoparticles have an aspect ratio in the range of 1:

3-1;

5.

6. The method of claim 1, wherein the nanoparticles have an axial diameter of approximately 10 nm and a longitudinal diameter in the range of 9 to 50 nm.

7. The method of claim 1, wherein the nanoparticles have a length of 40±

5 nm and a width of 10±

5 nm.

8. The method of claim 1, wherein the solution further comprises an anesthetic tumescent solution.

9. The method of claim 1, wherein the nanoparticles are functionalized with poly(ethylene-glycol).

10. The method of claim 1, wherein the beam area is within a range of 9 mm×

9 mm to 35 mm×

35 mm.

11. The method of claim 10, wherein the beam area is 2.3 cm×

3.5 cm.

12. The method of claim 1, wherein the beam energy is in a range of 1000 to 2000 J.

13. The method of claim 1, wherein the pulse duration is within a range of 30 ms to 60 ms.

14. A method of tightening skin around the target area according to claim 1.

15. A method for subcutaneous fat removal and skin tightening in a person in need thereof, the method comprising:

subcutaneously injecting a suspension of photo-absorbing gold nanorods in solution into a target region of adipose tissue of the person, wherein the nanorods have an aspect ratio in the range of 1;

3 to 1;

5;

scanning pulses of NIR light energy for a plurality of passes across an area of skin overlying the target region and into the injected suspension for an exposure duration, the NIR light energy having optical parameters selected from the group consisting of beam energy, pulse duration, emission wavelength within a range of 700 to 900 nm, emission intensity, beam focus and beam area, the optical parameters and the exposure duration selected to excite the nanoparticles to liquefy fat within the target region; and

extracting a liquid from the target region, the liquid comprising subcutaneous tissue, liquefied fat, and the injected suspension.

16. The method of claim 15, further comprises applying a cooling material to the area of skin overlying the target region after a subset of the plurality of passes.

17. The method of claim 15, wherein the emission wavelength is 800 nm±

10 nm.

18. The method of claim 15, wherein the gold nanorods have an axial diameter of approximately 10 nm and a longitudinal diameter in the range of 9 to 50 nm.

19. The method of claim 15, wherein the gold nanorods have a length of 40±

5 nm and a width of 10±

5 nm.

20. The method of claim 15, wherein the suspension has a concentration of 10¹¹ to 10¹³ GNR/mL in water.

21. The method of claim 20, wherein the suspension further comprises an anesthetic tumescent solution.

22. The method of claim 15, wherein the gold nanorods are functionalized with poly(ethylene-glycol).

23. The method of claim 15, wherein the beam area is within a range of 9 mm×

9 mm to 35 mm×

35 mm.

24. The method of claim 23, wherein the beam area is 2.3 cm×

3.5 cm.

25. The method of claim 15, wherein the beam energy is in a range of 1000 to 2000 J.

26. The method of claim 15, wherein the pulse duration is within a range of 30 ms to 60 ms.