Omar A. Ibrahimi, MD, PhD, hears some dermatology colleagues say they don’t bother to offer laser hair removal in their practices because they figure that the procedure is under the purview of medical spas, but he sees it differently.
Dr. Omar A. Ibrahimi
“I offer laser hair removal in my practice as a way to protect my patients from being picked off by medical spas,” Dr. Ibrahimi, a dermatologist and medical director of the Connecticut Skin Institute, said during a virtual course on laser and aesthetic skin therapy. “These patients are going to want to get laser hair removal. If they’re not going to have the opportunity to get it at your practice, they’re going to seek it elsewhere. When they go elsewhere, they’re going to be picked off for other procedures as well.”
First developed in 1995 by R. Rox Anderson, MD, and colleagues at The Wellman Center for Photomedicine, laser hair removal has become the gold standard for permanent hair destruction, and ranks as the most common energy-based procedure performed in the world, Dr. Ibrahimi said. “Results are very long lasting and durable beyond 2 years after treatment,” he said. “These patients tend to be highly satisfied and have permanence with these treatments.”
Treatment goal, patient selection
While the target chromophore for the procedure is melanin, the goal is to destroy the stem cells located in the hair bulge and the hair bulb. “This is technically called the extended theory of selective photothermolysis, but it’s the same concept except that our target chromophore and our desired target for destruction are slightly spatially separated,” he said.
Proper patient selection is key, so a focused medical history and physical exam are essential prior to the procedure. If unwanted hair is located on the face, jawline, or chest of a female, consider and ask about potential endocrine-related dysfunctions such as polycystic ovary syndrome (PCOS). “Getting those addressed can often help the hypertrichosis as well,” he said. “Another condition is explosive hypertrichosis where hair growth starts very suddenly. It’s uncommon but it’s something to think about.”
Pregnancy is not an absolute contraindication for laser hair removal, Dr. Ibrahimi continued, but he elects not to perform the procedure on pregnant patients. He also asks patients about any history of photosensitivity, active infection at the intended treatment site, keloids, or hypertrophic scarring. Past methods of hair removal also matter. “What we’re targeting is the pigment in the hair shafts,” he said. “So, if your patient is waxing or plucking or epilating or removing the hair in some manner, they’re actually removing the target chromophore.”
Patients with darker Fitzpatrick skin types can be treated safely but tanned individuals face a risk of complications because of active melanocytes. “As we approach summer in New England, we slow down the amount of hair removal we do because it’s a riskier procedure,” he said. “I recommend that my patients not get any significant amount of sun exposure a month before or after treatment.”
The color and quality of hair also drive treatment success. Black and brown terminal hairs absorb the millisecond laser energy, but white, gray, red, and light blond hairs lack adequate melanin to make them suitable target chromophores.
Excessive and unwanted body hair ranges in severity and can usually be classified as either hypertrichosis or hirsutism.
The desired clinical endpoint is perifollicular edema and erythema. Treatment parameters that can be varied with Food and Drug Administration–cleared devices include wavelength, fluence, pulse duration, spot size, and skin cooling. The most popular devices are the Alexandrite 755 nm laser; the diode 800 nm laser; and the 1064 nm Nd:YAG laser, which is safe for all skin types. “Often you have to use higher relative fluences to treat patients with the 1064 nm Nd:YAG because on the absorption spectrum, the 1064-nm wavelength has a relatively lower absorption for melanin compared to the alexandrite. However, you can still get effective, long-term hair reduction with the Nd:YAG laser,” he said (Arch Dermatol. 2008 Oct;144[10]:1323-7).
More recently, Dr. Ibrahimi and colleagues found that a 1060-nm diode laser system with multiple handpieces for permanent hair reduction was safe for all skin types, in an open label prospective study.
Higher fluences have been correlated with greater rates of permanent hair removal, but they also are more likely to cause undesired side effects. Dr. Ibrahimi advises clinicians new to laser hair removal to conduct a few different test spots and look for the desired clinical endpoint of perifollicular erythema and edema. “The highest fluence that gives you that endpoint without any adverse reactions is going to the best fluence for treatment,” he said at the meeting, which was named “Laser & Aesthetic Skin Therapy: What’s the Truth” and was sponsored by Harvard Medical School, Massachusetts General Hospital, and the Wellman Center for Photomedicine. “Do a few test spots, bring them back a week later and see which ones were tolerated well without any side effects and which weren’t. That gives you a good starting point for your treatment.”
Cooling down the epidermal melanin not only keeps the procedure safe, it’s a salve for pain. “There are a variety of methods of passive and active cooling,” said Dr. Ibrahimi, a member of the American Society for Dermatologic Surgery board of directors. “You can use something as simple as cold gel, but the active methods are better because once the method of passive application of cold gel warms up, you lose that cooling effect. You can use forced chilled air. Many commercial devices come with a cold tip which cools down the epidermal melanin. Others use dynamic cooling, which emit cryogen spray from a separate part of the handpiece. It hits right where the laser pulse is going to go, is absorbed by the skin, and it cools down the epidermal melanin.”