LAS VEGAS – Technologies to address the many skin changes associated with photoaging run the gamut from nonablative to ablative – and choosing the right technology for a given patient is a balancing act, according to Dr. Mathew Avram.
“Basically, it’s a trade-off between increased efficacy and increased side effects and downtime,” Dr. Avram said at the Skin Disease Education Foundation’s annual Las Vegas dermatology seminar.
Dr. Mathew Avram
Dr. Avram, director of the Massachusetts General Hospital dermatology, laser, and cosmetic center, Boston, said that traditional resurfacing remains the preferred method for repairing photodamaged skin. “One treatment provides reproducible, excellent results,” but at the cost of a significant amount of wound care and prolonged downtime. Potential adverse effects also include clear lines of demarcation with improper feathering, prolonged erythema, permanent hypopigmentation, infection, and scarring, he added.
For these reasons, the popularity of traditional resurfacing to treat photodamaged skin has declined over time as nonablative and intermediate techniques have arisen.
Intense pulsed light (IPL) is a nonlaser, nonablative technique that can produce overall skin rejuvenation, a “side effect” that patients often notice after they receive IPL for vascular lesions or hyperpigmentation. The benefits tend to be modest, even after several treatments, so this is not usually performed as a standalone technique for skin laxity or rhytides.
Nonablative fractional lasers act by creating thousands of microscopic wounds that are “columns of thermal coagulation,” leaving an intact stratum corneum, said Dr. Avram, who is also faculty director for laser and cosmetic training, Harvard Medical School, Boston.
The most common reason for treatment with a nonablative laser is mild to moderate wrinkles, though it can also be used for various pigmentation issues, as well as acne, surgical, and burn scars.
Although side effects are typically minor, the devices can be used off face, and there’s no worry about lines of demarcation; improvement is also more modest and will happen only with multiple treatments. “Fractional treatments give you fractional results,” Dr. Avram commented.
“You want to think about your treatment in terms of the pathology of what you’re treating,” he added, noting that fractional resurfacing can target both epidermal and dermal conditions. Examples of epidermal conditions that benefit from superficial treatment include dermatoheliosis, lentigines, and melasma.
Acne scars and deep wrinkles should receive deeper treatment in order to create thermal damage to the dermis proper, which, over a period of months, will trigger collagen remodeling and new collagen formation. Pulse energy will determine the depth and width of the zone of coagulation in the skin, so higher energy should be used with deeper skin pathology, Dr. Avram said.
Dermatologists also need to consider density of treatment – what percent of the skin is treated. “These devices go from about 5% to about 48% of skin coverage,” and increased density is really what increases the intensity of treatment, he noted. High-density treatment will result in more redness and swelling and has a greater potential for hyperpigmentation, but will not necessarily yield increased benefit in treatment outcomes, he added.
Pretreatment considerations should include assessing the patient’s expectations and availability for downtime post procedure. Treatment planning should also consider the patient’s skin type and probability for sun exposure. Patients should know they will see only partial improvement in wrinkles, scars, and pigmentation, and should expect some discomfort during the procedure and some side effects and healing time post procedure. Patients with a history of herpes labialis should receive valacyclovir 500 mg twice daily, beginning the day before treatment and continuing for 5-7 days, Dr. Avram said.
Cold-air cooling makes the treatment both safer and more comfortable, he pointed out. Topical compounded anesthesia including higher percentages of lidocaine and tetracaine can also be effective. Though local injected anesthesia can be effective in focal treatment of scars, the injection should be deep, and treatment should not begin immediately. This allows the lidocaine to disperse, minimizing the risk of ulceration from the thermal instability that a depot of lidocaine could cause, he said.
Fractional lasers can also be effective for treating background dermatoheliosis, as opposed to targeted treatment of individual lentigines. “Fractional is going to be great for clearing background damage,” Dr. Avram said.
A hybrid technique called ablative fractional photothermolysis creates tiny columns of ablation, while leaving the surrounding untreated tissue available as a reservoir for rapid healing. This technique will improve the more severe wrinkles that nonablative treatments don’t help, with less downtime than a fully ablative technique. Interestingly, patients have less postprocedure pain with this technique than with nonablative techniques, probably because the ablated channels offer a way for heat to escape the skin, he said