Laser parameter selection in darker skin
Tips for lowering risk of pigment change following laser treatment of skin conditions (1,500 words, 7 minutes)
Thermal laser skin treatments carry some risk of inducing unwanted pigmentation changes in darker skin types. Choosing the correct parameters can reduce these risks and improve patient outcomes, said Dr. Jaggi Rao during a presentation at the 8th annual Skin Spectrum Summit.
Dr. Rao is a clinical professor in the Faculty of Medicine and Dentistry at the University of Alberta in Edmonton and the founder and team lead of ConsultDerm, a national teledermatology project.
When using thermal lasers on darker skin, caution is needed, said Dr. Rao. He listed several factors to consider for minimizing damage to both the epidermis and dermis:
Longer wavelengths are generally safer in darker skin types. Water-specific 2,940 nm lasers can be used for precise ablation with a reduced chance of bulk heating
Conservative parameters should be chosen, including lower fluences, lower density, and longer pulse duration
Local site cooling using ice, a sapphire lens, or other cold contact is particularly important
Dr. Rao also recommended some adjunctive treatments, such as decreasing sun exposure, lightening regimens to address post-inflammatory dyspigmentation, and steroid applications.
As an example of considerations for laser use in darker skin, Dr. Rao also discussed the case of a patient with epidermal melasma. Dr. Rao used laser treatment to accelerate exfoliation to reduce the pigment in the skin. However, he said it is important to caution the patient that in the first three days after treatment, the pigmentation will get darker. This may cause the patient to think the condition has gotten worse if they are not alerted in advance.
Fractional ablative lasers work well for deeper postinflammatory pigmentation, inducing transepidermal elimination of the pigment that is deeper in the skin, Dr. Rao said. The laser wounds will close in about a week and the pigment will rise from the dermis to the surface, leaving the patient with less pigment.
Bottom Line: When using lasers on darker-skinned patients, parameters should be chosen that reduce the risk of inducing unwanted pigmentation. These include using longer wavelengths and pulse durations, and less energy and density. Cooling is very important during treatment.
From the literature on energy devices and skin of colour
An increased amount of hair reduction using laser correlates with a lower probability of recurrence in patients with pilonidal disease
The findings from this study suggest that patients with Fitzpatrick skin types V and VI and dark hair are more likely to have their pilonidal disease (PD) reoccur, and those with dark-coloured and thick hair require more laser epilation (LE) sessions to achieve a degree of hair reduction that may reduce recurrence risk.
The study was conducted to test the hypothesis that greater hair reduction achieved using a laser could correlate with a lower chance of PD recurrence.
A total of 198 PD patients were recruited—21 with skin types I and II, 156 with skin types III and IV, and 21 with skin types V and VI. The median time to follow up after LE was 217 days. The investigators found that 95%, 70%, 40%, and 19% of patients reached 20%, 50%, 75%, and 90% hair reduction after mean LE sessions of 2.6, 4.3, 6.6, and 7.8 sessions, respectively. To achieve 75% hair reduction, patients required a mean of 4.8-6.8 LE sessions, depending on different skin/hair characteristics. The PD recurrence rate was 6%. Probability of recurrence after 20%, 50%, and 75% hair reduction was decreased by 50%, 78%, and 100%, respectively. Dark hair and skin type 5/6 were associated with higher recurrence rates.
Skin phototype of participants in laser and light treatments of cosmetic dermatologic conditions: A systematic review
Researchers conducted this review to understand the representation of participants with skin phototypes IV to VI in cosmetic dermatologic trials studying laser and light devices.
The investigators searched the PubMed and Web of Science databases for randomized clinical trials published between Jan. 1, 2010, and Oct. 14, 2021, that studied laser or light devices for cosmetic dermatologic conditions. Overall, they evaluated 461 randomized clinical trials, that represented 14,763 participants.
They found 345 studies reported skin phototypes. Of those, 81.7% (n=282) included participants of skin phototypes IV to VI, but only 27.5% (n=95) included participants of skin phototypes V or VI. They write that this trend of excluding darker skin phototypes persisted when results were stratified by condition, laser of study, study location, journal type, and funding source.
Prospective study of efficacy and safety of non-ablative 1,927 nm fractional thulium fibre laser in Asian skin photoaging
To evaluate a 1,927 nm fractional thulium fibre (FTL) laser as a treatment for photoaging in Asian skin, research recruited 27 patients with Fitzpatrick skin types II to IV.
At one-month intervals, patients received three full face laser treatments. The researchers measured wrinkles, spots, texture, pores, melanin index, erythema index (MI and EI), skin elasticity and hydration. They compared epidermal thickness and dermal density on ultrasonography between baseline and one month after all treatment sessions. Two independent evaluators rated the Global Score for Photoaging scale (GSP) at baseline and final follow-up visits.
The findings suggest that the epidermal thickness significantly improved after treatment. The authors noted statistically significant improvements in melanin index, skin elasticity and wrinkles. Patient comments showed that 12 subjects (44%) wrote their skin felt brighter. No post-inflammatory hyperpigmentation changes or adverse events were observed. Some 70% of patients reported they were “satisfied” or “extremely satisfied”.
Comparison of the efficacy and safety of picosecond Nd:YAG laser (1,064 nm), picosecond alexandrite laser (755 nm) and 2% hydroquinone cream in the treatment of melasma: A randomized, controlled, assessor-blinded trial
Researchers compared the efficacy and safety of non-fractional picosecond Nd:YAG laser (PSNYL), non-fractional picosecond alexandrite laser (PSAL), and 2% hydroquinone (HQ) cream in the treatment of melasma in patients with Fitzpatrick skin types III to IV.
The patients were randomized into three groups (PSNY, PSAL, and HQ) at a 1:1:1 ratio. Patients in the PSNYL and PSAL groups received three laser sessions at four-week intervals. The 2% HQ cream was applied twice daily for 12 weeks in patients of the HQ group. Researchers evaluated the melasma area and severity index (MASI) score, which was evaluated at weeks zero, four, eight, 12, 16, 20, and 24. Patients reported their assessment scores by quartile rating scale at weeks 12, 16, 20, and 24.
Researchers included 59 subjects in the final analysis. Each group showed significant change from baseline in MASI scores from week four to week 24. The MASI score in the PSNYL group showed the greatest reduction compared to the PSAL group (p=0.016) and HQ group (p=0.018). The PSAL group demonstrated comparable MASI improvement as the HQ group (p=0.998). The PSNYL group had the highest patient assessment score, followed by the PSAL group and then the HQ group, although only the differences between PSNYL and HQ groups at weeks 12 and 16 were significant. Four patients (6.8%) experienced recurrence. Other unanticipated events were transient and subsided after one week to six months.
VIDEO: Best lasers for skin of colour—Dr. Stefani Kappel, cosmetic dermatologist, Corona Del Mar, Calif.
At the intersection of skin and society
On May 26, the Crave and APTN Lumi streaming platforms debuted the first episode of Little Bird, a six-episode limited series drama. The series tells the story of an Indigenous woman seeking her birth family after being separated from them as a child as part of the so-called “Sixties Scoop,” a government policy that separated many Indigenous families.
According to a press release, actor Darla Contois plays Bezhig Little Bird, who was removed from her home in Long Pine Reserve in Saskatchewan. Adopted into a Montréal Jewish family at age five and given the name Esther Rosenblum, Bezhig is in her 20s in 1985, when she sets out to find her birth family.
Showrunner and co-creator of Little Bird, Jennifer Podemski, says in a second release that careful consideration of the tone and approach to this sensitive topic was crucial.
“I do feel that we achieved the tone we wanted,” Podemski said. “This is a delicate balance between psychological and social. It’s social commentary, but it’s also a psychological, internalized history. And that’s a very strange mix of tones. I think what we were trying to do was find what it means to have an Indigenous perspective. And what I could filter it, or distill it, down to was there’s always a lingering feeling of colonialism mixed with your own internalized sort of intergenerational or lived trauma. Those things intertwine in a way that makes everything feel a little bit uneasy.”
This week
June is LGBT Pride Month
June 5 is World Environment Day
June 5 to 11 is Hidradenitis Suppurativa Awareness Week
Something to think about in the week ahead...
— Peter Drucker, U.S. businessman, 1909-2005
Next week
At the Meeting the Challenge Summit, key stakeholders across the clinical trial ecosystem met to advance discussions regarding the need for broader inclusion of racial and ethnic minority patients in dermatology clinical trials. The Summit was hosted by The Skin of Colour Society in Washington, D.C., in June 2022.
As part of that meeting, stakeholders identified several barriers to diversity in dermatology clinical trials and discussed strategies to overcome those barriers.
If you like Skin Spectrum Weekly, why not check out Chronicle’s other publications, podcasts, and portal?
Established in 1995, The Chronicle of Skin & Allergy is a scientific newspaper print providing news and information on practical therapeutics and clinical progress in dermatologic medicine. The latest issue features:
Dr. Jerry Tan (Windsor, Ont.) discusses recent findings on the presentation and prevalence of truncal acne
Drs. Jaggi Rao (Edmonton), Maxwell Sauder (Toronto), and Jason Rivers (Vancouver) give their thoughts on skin cancer prevention and how to increase the adoption of sun-safe habits among the population.
An essay from Dr. Munirah Aljaser (Montreal) submitted to the 2022 Dermatology Industry Taskforce on Inclusion, Diversity and Equity (DiTiDE) short essay contest. Dr. Aljaser wrote on the challenge of changing the cultural perception that lighter-coloured skin is more beautiful.
Plus regular features, including the popular column “Vender on Psoriasis” by Hamilton, Ont. dermatologist Dr. Ron Vender
Read a recent digital edition here. To apply for a complimentary* subscription or to receive a sample copy, please email health@chronicle.org with your contact information.
The Women in Dermatology e-newsletter updates new findings concerning dermatologic issues that affect women and the female dermatologists who care for them. Read the current issue here.
Season two of the Shear Listening Pleasure podcast with Dr. Neil Shear has launched. Listen to the eighth episode here, where Dr. Shear speaks with dermatologist Dr. Sonja Molin (Kingston, Ont.) about allergology, patch testing, and the growth of Queen’s University’s dermatology division.
And if you’re looking for a web destination for all things derm, please visit derm.city, “Where Dermatology Lives.” Please like, rate, review, and share it with your colleagues.