The Procedure for Laser Resurfacing

The procedure for laser resurfacing and laser treatment for acne

The procedure for application of lasers for treating the face for the photoaging or laser treatment for acne start with anesthesia. The following protocol is applied for the procedure.

After washing the face with warm, soapy water and applying hot compresses for 10 minutes, the patient applies 30 g of EMLA® cream under occlusion.

Ninety minutes later, the patient is given some medications.

An additional 300 g of EMLA cream is applied under occlusion. By this time the cream already applied is fully absorbed. Anatomic areas are covered with individual pieces of plastic wrap. Special care is taken to avoid any skip areas.

Actual wLaser treatment

The patients are generally given a test treatment with laser to determine their tolerance level. If the patient feels uncomfortable, additional anesthesia by injection is applied. Use of nerve blocks is usually recommended to enhance the ease of the procedure.

When using CO₂ lasers, the laser is performed in sections. Occlusive wrap is removed from an area, EMLA® cream is wiped on with dry gauze immediately prior to treatment and that section is treated before proceeding to the next area to be treated.

The procedure is generally performed in a series of passes, the number of which depend on the skin condition to be treated.

The first pass - Removal of the epidermis

The first pass is generally performed for the removal of the epidermis and is feathered peripherally to minimize the lines of demarcation with the areas of the skin which are untreated.

The hydration of the skin achieved during the anesthesia protocol allows for the use of higher densities of laser light for effective removal of epidermis. The treatment is generally feathered on the cheeks with densities of 6-7 and energy of around 90mj. When moving towards the hair and jaw lines, the densities are generally decreased. Further down the neck the densities are further decreased. Special care needs to be taken for application at the angle of mandible and neck because of the thin skin in this area.

After the treatment, the epidermis is wiped off the central face but never on the periphery and the neck.

The second pass

The second pass with the lasers are generally performed for the transfer of heat to the tissue to produce tightening. The densities of the lasers used here are around 4 and 5 depending upon the tightening desired, for examples the upper eyelids can be treated with densities of 5 where as the lower eyelids and mid cheeks can be treated with densities of 4. Lateral cheeks are rarely treated with the second pass unless an acne scar is present there.

The third pass

The third pass with the lasers are generally performed on acne scars to deliver extra heat to enhance skin tightening.

The RE:YAG lasers with a short pulse can also be used for superficial thermal necrosis and to further sculpt the deep rhytids or acne scars treated with CO₂ lasers.

Conversely, some laser surgeons will start with the sculpting pass over ridges of acne scars and deep lines and then will proceed with the remaining areas.

If a greater depth of tissue ablation, is needed for example the destruction of a thick seborrheic keratosis, intradermal nevus, syringoma, or sebaceous hyperplasia, a well marked smaller spot size with higher density of CO₂ can be used, or alternately, a single spot erbium laser can be used to ablate the lesions.

It is to be remembered that the laser resurfacing has two actions on the target tissue, ablation and coagulation. Longer pulse widths, like those from CO₂ and erbium lasers, deposit more heat and therefore achieve more coagulation and more abalation, whereas short pulse widths (ER:YG0) more purely ablate the tissue without coagulation.

Typical treatment settings for a woman with photodamage and perioral wrinkling might be as follows:

• first pass: 100 microns ablation;
• second pass: 50–100 microns coagulation;
• third pass: 25 microns ablation and 50 microns coagulation;
• sculpting pass over deepest lip lines with 50 microns ablation.

In conclusion, ablative laser resurfacing with CO₂ provides cosmetic improvement unparalleled by other available laser and light source techniques. The visible wound contraction and high degree of coagulation is not possible with any other laser system.

But the best results with surgery can be observed by combining the procedure with other lasers where some of the side effects of the CO₂ lasers can be avoided. The common goal here being to achieve a significant degree of clinical improvement with less morbidity, which is the main disadvantage of existing CO₂ laser technology. All of these novel systems aim to produce the degree of coagulation, the tissue granulation and fibroplasia seen with the CO₂ laser, but thin zones of thermal damage (50–100 µm compared with 150 µm) with a combination of a CO₂ laser and an Er:YAG laser. The combination ensures that the thermal effect of the CO₂ laser is sufficient to stimulate collagen remodeling, whereas part of the thermal necrosis zone is removed by the purely ablative device, thus minimizing the time of the healing process.

On average the laser resurfacing is a promising technique for phtodamaged skin and laser treatment for acne.

References:
1.E. Papadavid,and A. Katsambas, “Lasers for facial rejuvenation: a review”, 2003, The International Society of Dermatology, 42, 480–487
2.D. Railan, and S. Kimlmer, “Ablative treatment of photoaging”, Dermatologic Therapy, Vol. 18, 2005, 227–241