▶ Previous Artlcle : #16-3. Yellow Laser
In the case of pigmented lesions, as shown in <Figure 4>, the 511nm wavelength has a high absorbance for melanin, so it can be used for the treatment of freckles or black lesions.
However, Yellow Laser is not necessarily used for the treatment of such lesions because the parameters must be continuously changed for treatment.
This is because it takes longer to change parameters than Q-switched 532nm laser, Q-switched 694nm laser, and Q-switched 755nm laser.
[Advertisement] Reandnè Thread Series – Manufacturer: GTG KOREA(www.gtgkorea.co.kr)
However, for pigmentation accompanied by vascular melasma or redness, combination treatment with Q-switched Nd:YAG laser toning or Picosecond laser toning can simultaneously treat redness and pigmentation a little faster.
Benign tumor lesions such as flat warts and age spots are thick, so the photothermal effect should be increased by using a wavelength of 511nm, which has a high absorbance for melanin, and the laser should be irradiated to make it penetrate a little deeper by using a wavelength of 578nm and having the ratio of 511nm and 578nm 50:50 (Figure 5).
During laser irradiation, in the case of flat warts, the end point to be observed is the phenomena that the color changes to ash gray or the lesion bursts with a “tick” sound or swells.
Figure 3. Chromophore (oxyhemoglobin) of 578nm wavelength.
-To be continued
