Investigate the Effect of Small Spot Size and Fluence for Laser Hair Removal in Lanyu Pigs Yu-Wei Chiang1 Yao-Chang Liao21

Kai-Jung Chen1 I-Ku Kuo2

Chih-Yen Lin1 Kao-Chi Chung1*

Institute of Biomedical Engineering, National Cheng Kung University 2 Kera Harvest Inc. *Corresponding Emailkaochi@mail.bme.ncku.edu.tw

(618 mm) 11.52 mm (A)(B) 808 nm 1 mm40 J/cm2 Abstract In order to achieve the efficacy of Laser hair removal, laser system usually adopt a large spot (Diameter 6~18 mm) for treatment. Although the treatment time could be reduced, big spot will cause unnecessary tissue thermal injury near hair follicle. The purpose of this research is to investigate small spot size on hair removal (Diameter 11.52 mm). This research utilizes animal testing (Lanyu pig) to probe the feasibility of hair removal by small spot size and laser diode system application. There are two specific purposes of this research. (A) First, to design the prototype of small spot size laser diode system.(B) Second, to design the animal testing of Lanyu pig. Here we use 808 nm laser source, hand piece device, and optical mechanism design. Also, we verify the power, spot size and pulse width. To

apply on animal model and selection treatment parts by the leading experimental data , the layer thickness of porcine abdominal skin , hair structure , are similar to human. We confirmed that Lanyu pig is the appropriate animal model for laser hair removal. We did a section and staining for tissue of pig skin. The results show that when conditions are within 1 mm spot size, fluence 40 J/cm2, there is some outer root damage, hair shaft structural disintegration, the hair follicles swelling around, and the vacuoles presenting within the hair shaft after injection. Therefore, we prove that small spot size laser has the feasibility on hair removal; it could be a new treatment of laser hair removal. Keywords: Laser Hair Removal, Spot Size, Lanyu Pig. ( 618 mm) 11.52 mm A B A. (a) (b)(c)

(a) 808 nm20 W (200 mN.A.0.22 SMA 905 ) 6V/20A RS232( )

mm 1mm 1.5mm 2mm f 40 30 20 p 48 34 22 q 240 255 220 D 40 30 20 ho 6.75 4.78 3.09 s 17.79 40.02 71.15 M 5 7.5 10

() p 5. 4. q 4.2. 1 11.52 mm 1 1 2 1 3 (M3-4) 4 (Y49-481) 5 6 2 7 (MSV2_6) 8 (SM05SMA) 9 3 10

(b) f D a O p() O b q( ) o a hop tan(o) () o8 200m 11.52 mm M 57.510

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10 30 60 20 40 50 70 ms 5 N-SF11 (0.7 @7501550 nm) B. () () () ()

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III. ()() (a) (b) (c) (d) (e) (f) (g) () (a) (b) (c) (d) (e) (f) (g) (h)

50120 m 30140 m 10 : 1 13 : 1[24]

() () (A) (a) y = 2.3901x - 4.5128 R = 0.99

(Arrector pili muscle)(Sweat glands) (Collagen fibers)(Elastic fibers) (Medulla) (Cortex)(Internal root sheath) (Outer root sheath)[24] () (Biopsy punch) () [3] II.

20 18 16 14 12 10 8 6 4 2 0 2 3

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y = 2.5696x - 4.6167 R= 0.997

4

5

6

7

8

9

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(A)

618 mm 10 50 J/cm2 1 1.52 mm203040 J/cm2 [4]

(b) ()( = 0.8321= 0.863mm)() (= 1.421mm= 1.382() (= 1.926= 1.954mm)

() 1 mm 40 J/cm2

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(HE ) (a) (b) 1 mm 40 J/cm2 [1] G.B. Altshuler, R.R. Anderson,D. Manstein ,H.H. Zenzie, and M.Z. Smirnov (2001) Lasers in Surgery and Medicine, 29:416-432. Tory P. Sullivan, William H. Eaglstein, Stephen C. Davis, Patricia Mertz, (2001) Wound Repaair and Regeneration , 9:66-76. Nina Otberg, Heike Richter, Hans Schaefer, Ulrike Blume-Peytavi, Wolfram Sterry, and Jrgen Lademann (2004) The Journal of Investigative Dermatology,122:14-19. Lin. TY, Manuskiatti W, Dierickx C.C., Farinelli WA, Fisher ME, Flotte T, Baden HP, Anderson RR. (1998) J Invest Dermatol. , 111:107-113.

1

2

3 10.2 20.0 29.8 40.0 50.0 60.2 70.2

4 10.2 19.8 30.2 39.8 50.1 59.8 70.0

5 9.8 20.0 30.0 40.2 50.2 60.1 70.0

Mean SD 10.04 19.92 30.00 40.04 50.02 60.02 70.00 0.17 0.11 0.14 0.17 0.15 0.15 0.14

10 20 30 40 50 60 70

10.0 10.0 20.0 19.8 30.0 30.0 40.0 40.2 50.0 49.8 60.0 60.0 70.0 69.8

[2] [3]

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[4]

(DY-01-01-04-98)

(HE ) (A)(B) ()