How does skin rejuvenation work with the Picosecond Laser?
Traditional ablative lasers like the erbium laser, the CO2 laser, the fractionated erbium and CO2 lasers are excellent for the treatment of deeper scars, deeper wrinkles (smokers’ lines), facial rhytids (pillow lines, keratoses, solar elastosis, etc). However, there is downtime with some degree of initial redness for a few days and pinkness for another few weeks with these ablative lasers. The results are excellent and for those patients who are able to allow appropriate recovery, these ablative treatments are still the gold standard.
However, patients who want an improvement in the texture, color, tone and laxity of their skin don’t always have the required down time. In such patients, the new picosecond lasers give excellent results by addressing the skin in different ways.
By using appropriate energy (around 3J/cm2) and spot size and delivery system, it was found that long pulse lasers using 300 msec, 600 msec, and picosecond lasers all allow tissue tightening with resulting improvement in skin wrinkles, age lines, acne scars and some degree of skin tightening (especially when combined with other techniques like subdermal radio-frequency and high-intensity focused ultrasound).
Picosecond lasers activate subdermal changes which stimulate an immunological response known as cell signaling: biological communication occurs because of cell changes with release of proteins and a secondary healing response. Intra-epidermal Laser Induced Optical Breakdowns (LIOPS) form and form pressure waves which secondarily affct the dermis and trigger activation of cells. Increased formation of collagen and elastin results in tightening of tissues, improvement in acne scars and improvement in texture and wrinkles.
It is thought that skin immune responses are stimulated resulting in minimal heat-related changes, minimal discomfort and only mild erythema which lasts a few hours.
The other modality of action is the improvement in pigmentary changes and vascular changes related to solar elastosis, age, etc. Not only is there improvement in discoloration of the skin (improvement in freckles, sun-related spots, skin discoloration, etc) but also a gentle but defined improvement in the skin texture and color. Vascular changes from sun-damage are improved with the appropriate wavelength settings.
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