Intense pulsed light (IPL) technology has become a popular tool in the cosmetics industry for treating various skin conditions. This non-invasive, pain-free procedure uses a broad spectrum of light waves to target specific skin conditions, such as acne, rosacea, pigmentation, and hair removal.

Cosmetic practitioners ensure that the IPL technology is used safely and effectively to achieve optimal results. In this article, we share our experience using IPL technology, our challenges, and the methods employed to overcome them.

Our clinic uses IPL machines that are calibrated to address specific skin concerns. We followed strict protocols while performing IPL treatment, starting with a thorough client consultation to understand their skin type, concerns, and medical history. Based on this, we tailored the IPL treatment to their needs.

IPL therapy is a non-invasive treatment for post-inflammatory hyperpigmentation (PIH) that targets melanin in the skin using high-intensity light pulses [1,2]. This involves the absorption of light energy by melanin molecules, which is then converted into heat energy. This causes melanin coagulation, leading to its destruction. The IPL device delivers a broad light spectrum with varying wavelengths, allowing the selective targeting of different pigments in the skin.

IPL therapy targets melanocytes that produce melanin and stimulates collagen production, promoting skin rejuvenation [3,4]. The heat generated during IPL therapy destroys blood vessels, aiding in the overall reduction of hyperpigmentation. In addition, IPL therapy can improve the overall texture and tone of the skin by minimizing the appearance of scars and fine lines [5].

Overall, IPL therapy is an effective, non-invasive treatment for PIH that targets melanin and promotes skin rejuvenation via collagen production.

The parameter settings vary between treatments, inter-, and intraoperatively, depending on the tissues treated, skin type, and patient condition. Physicians should be aware of the contraindications to light therapy (Table 1).

Table 1 . Contraindication of intense pulsed light therapy.

1) Use of photosensitizing agents, e.g., accutane, topical retinoids before treatment.

2) History of skin cancers

3) Pregnancy

4) Too dark skin tones

5) Uncovered active skin infection

Table 2 lists what physicians and patients should do before IPL treatment.

Table 2 . Before intense pulsed light treatment.

1) The patients are assisted/requested to wash their faces with a neutral solution 10 minutes before photos are taken in the same treatment room under the same light conditions. No make-up or skin care products are allowed on the face.

2) Photographs are taken before the commencement of each session. The front and both sides laterally & obliquely are taken. They are helpful for evaluations of treatment results.

Table 3 lists what physicians need to be aware of during IPL treatment.

Table 3 . During intense pulsed light treatment.

1) The patients are provided with a shower cap to avoid any hair damage.

2) To protect their eyes, they all wear eyeshields (corneal shields are not required) and are instructed to keep their eyes shut throughout the treatment.

3) The face is covered evenly with a layer of about 5 mm thick chilled (4°C) colorless coupling gel.

4) The upper lip area in males is spared from any treatment to preserve normal facial hair distribution.

5) The immediate skin response after 3 adjacent pulses on the test area is checked. Following this, the fluence and/or relaxation time are adjusted accordingly. Purpura or PIH from previous treatments are noted, and the pulse parameters are adjusted for subsequent treatments.

6) Initial treatment: low and safe setting

7) Observe for any severe post-treatment erythema

8) Slowly increase power in small steps with each successive treatment

Table 4 lists the IPL treatment recommendations.

Table 4 . Recommendation of intense pulsed light treatment.

1) Number of treatments: 7–10

2) Treatment intervals: every 3–4 weeks

3) Analgesia: without any topical anesthetic cream or general anesthesia, only cold gel is needed on the whole face throughout the procedure

4) Post-procedural care: moisturizers, sunblock application, and sun avoidance advice

Table 5 lists the usual parameters used in our clinic; this setting may not suit every patient, and physicians should assess the best parameters case by case. All the patients in the below case presentations had informed consent.

Table 5 . Intense pulsed light treatment parameters.

Cutoff filters: 560 nm, 590 nm, 640 nm, 695 nm

Energy output: 1–40 J/cm2

Pulse widths: 3–100 ms

Pulse delay (thermal relaxation time): 1–120 ms

Triple pulses for 590 nm, 640 nm, and 695 nm filters

Double pulses for 560 nm, 640 nm filters

Duration: 20–25 minutes

A 30-year-old Chinese housewife presented with a 3-year history of a pigmented right forearm lesion. She visited multiple general practitioners and dermatologists and was told that the pigmentation would improve. One general practitioner prescribed topical 4% hydroquinone cream, but there was no noticeable improvement. She reported that the pigmented lesion was caused by boiling water accidentally splashing on her forearm approximately 3 years ago. It was small at first but grew, with discoloration of the surrounding skin, 6 months after the accident. She was a non-smoker and non-drinker with no significant past medical history.

Physical examination showed a 2.5 cm×2.5 cm circular brown pigmented patch over the distal dorsal aspect of her right forearm, with a 0.5 cm×0.5 cm T-shaped hypertrophic scar and small macules of postinflammatory hypopigmentation in the surrounding skin tissue (Fig. 1A). There were no similar lesions on other parts of her body.

Figure 1. (A) Case 1 PIH before 1st IPL treatment. (B) Case 1 PIH after 12th IPL treatment (76 weeks later). PIH, post-inflammatory hyperpigmentation; IPL, intense pulsed light.

The patient underwent 12 IPL treatments (using a Lumenis M22 OPT machine; Lumenis Be Ltd. Yokneam, Israel). The patient was satisfied with the outcome (Fig. 1B). There was no recurrence of PIH, the patch of nearby postinflammatory hypopigmentation, or the T-shaped hypertrophic scar, which resolved during IPL treatment, an advantage of this treatment.

A 35-year-old Chinese female company secretary presented with a 1-year history of bilateral hyperpigmented malar patches. She received IPL therapy at the facial skin rejuvenation beauty center. Unfortunately, her treatment was performed by an inexperienced therapist, resulting in severe pain after a particular treatment. Immediately after treatment, she found two right-sided erythematous malar patches and one on her left. The patient was told she could leave it alone and the pigmentation would improve. The erythema decreased in severity but later became hyperpigmented. One general practitioner diagnosed the patient with PIH post-IPL burn. The patient was prescribed topical 4% hydroquinone cream and did not experience any improvement after 26 weeks of application. She had no significant past medical history and was a non-smoker and non-drinker.

Physical examination revealed two (1 cm×1 cm) right-sided, oval-shaped hyperpigmented malar patches (Fig. 2A) and one (1 cm×1 cm) on her left (Fig. 2B). The patient did not have similar lesions on other parts of her body.

Figure 2. (A) Case 2 PIH (right face, before IPL treatment). (B) Case 2 PIH (left face, before IPL treatment). (C) Case 2 PIH after 10th IPL treatment (right face), (D) Case 2 PIH after 10th IPL treatment (left face). PIH, post-inflammatory hyperpigmentation; IPL, intense pulsed light.

The patient underwent 10 IPL treatments (using a Lumenis M22 OPT machine).

After the 10th IPL Treatment, the patient was satisfied with the clinical results (Fig. 2C, D).

A 40-year-old female Filipino housekeeper presented with a 4-year history of bilateral hyperpigmented malar patches. She underwent nanosecond laser treatment at a beauty center for melasma. Despite a physician performing her treatment, she experienced darkening of the lesions after each laser treatment. She came to Hong Kong for new work, and her boss brought her to our clinic. The patient was diagnosed with PIH post-laser burn. We suggested that IPL treatment be administered to reduce the severity of pigmentation. Hydroquinone cream was not prescribed. She had no significant past medical history and was a non-smoker and non-drinker.

Physical examination showed that the patient had two discrete clear-bordered dark patches over her mid-cheek (Fig. 3A, B), but she had no similar lesions on other parts of her body.

Figure 3. (A) Case 3 PIH (right face, before IPL treatment). (B) Case 3 PIH (left face, before IPL treatment). (C) Case 3 PIH (right face, after 22 IPL treatment). (D) Case 3 PIH (left face, after 22 IPL treatment). PIH, post-inflammatory hyperpigmentation; IPL, intense pulsed light.

The patient underwent 22 IPL treatments (with a Lumenis M22 OPT machine) and was satisfied with the result (Fig. 3C, D).

IPL involves applying a non-coherent, non-laser broadband, filtered flash lamp source directly to the skin. The modification of various parameters allows for flexibility in the treatment. IPL is effective for hair removal, inflammatory skin diseases such as acne vulgaris and rosacea, pigmentation disorders such as melasma, and skin photorejuvenation [5].

One of the challenges we face while using IPL technology is ensuring our clients’ safety. To mitigate the risk of adverse side effects, we performed a patch test on a small area of skin before proceeding with the full treatment. This allows us to assess how the skin reacts to the IPL and adjust the settings if necessary.

Another challenge we encountered was educating clients on the importance of proper aftercare. We provided our clients with detailed instructions on how to care for their skin after treatment, such as avoiding direct sunlight, using sunscreen, and avoiding harsh skincare products.

Despite these challenges, we have successfully used IPL to treat various cosmetic concerns, from reducing redness and pigmentation to eliminating unwanted hair. Importantly, IPL technology is not a one-size-fits-all solution and should only be performed by qualified and experienced professionals.

We hope our experience and insights will be valuable to other cosmetic practitioners considering incorporating IPL technology into their practice. With proper safety measures and tailored treatments, IPL can be a safe and effective method to achieve a more radiant and youthful complex.

PIH is a common cutaneous disorder that occurs following inflammatory conditions such as acne, eczema, and contact dermatitis, but the exact pathogenesis is unclear. Hyperpigmentation in PIH is caused by melanin overproduction by melanocytes. Inflammatory mediators stimulate the proliferation and activation of melanocytes and increase the expression of melanogenic enzymes. Melanocytes then migrate to the epidermis, producing more pigments that accumulate in keratinocytes. Some pigments are also deposited in the dermis. Studies have suggested that cytokines, reactive oxygen species, and genetic factors play significant roles in the development of PIH.

Our case series had an extended follow-up and high-resolution pre-, on-, and post-treatment clinical photographs to demonstrate the progress of PIH. Furthermore, the hypertrophic scar, hyperpigmentation, and post-inflammatory hypopigmentation surrounding the area in case 1 also improved with the recovery of normal skin color after the entire treatment course. We did not use intralesional steroids to improve scarring, which is an alternative treatment option for patients with steroidphobia [6]. Moreover, our cases had different causes of PIH, which increased the difficulty of persuading our patients to believe they could be treated with light treatment, especially in cases 2 and 3, where IPL and laser treatment caused their PIH lesions.

Only one study on PUBMED used IPL to treat PIH. Park et al. [7] evaluated the clinical efficacy and safety of a novel pulse-in-pulse mode IPL treatment in 25 Korean female patients with persistent facial PIH. After 2 months of treatment, 92% of the patients showed >50% improvement, and 88% were satisfied with the result. The pulse-in-pulse mode IPL treatment is effective and safe for treating persistent facial PIH in patients with dark skin. Although IPL is not a conventional therapy for PIH, there is evidence that it is effective.

IPL technology has been used for many years, with different indications for multiple skin diseases. There have been reports on the treatment of vascular diseases and pigmented lesions. Nevertheless, as laser treatments have become more popular among patients and physicians, IPL treatments have become less eye-catching. Our team has been focusing on IPL technology for 20 years, and we hope that our reports on treating severe conditions [8-10] will drive physicians to conduct more research on this valuable technology.

In conclusion, our experience using IPL technology has allowed us to treat various skin concerns safely and effectively while providing a positive experience for our clients. Our approach involved conducting thorough consultations, performing patch tests, and educating patients on proper aftercare to mitigate adverse side effects. We hope our experiences and insights will assist other practitioners in incorporating this technology into their practice, ensuring safe and successful results for their clients. IPL technology continues to be a valuable tool in the cosmetics industry, offering a non-invasive and pain-free solution for enhancing the skin’s overall appearance.

The authors have nothing to disclose.