Hair stimulation following laser and intense pulsed light photo-epilation: Review of 543 cases and ways to manage it

A review of hair removal modalities in pediatric patients: Ethical and clinical considerations

Unwanted hair is a common concern among patients presenting to pediatric dermatology clinics, and parents and patients alike inquire about the safety of methods employed for elective removal. Various methods of hair removal exist with different levels of invasiveness and permanence, from simple mechanical depilation to light-based therapies. All methods of hair removal appear to be safe and generally well tolerated in children, and there are no age restrictions to any modality. In this review, we aim to address the available literature on the safety and efficacy of hair removal modalities in pediatric patients and propose guidance on how to manage requests for at-home and in-office therapies within an ethical framework.

What are the Factors That Induce Paradoxical Hypertrichosis After Laser Hair Removal?

BACKGROUND

Laser hair removal (LHR) is one of the most requested cosmetic procedures worldwide. A rare side effect is the appearance of excess hair around previously treated areas, known as paradoxical hypertrichosis.

OBJECTIVES

The aim of this study was to retrospectively identify the cause of this side effect.

METHODS

This study included all patients who underwent LHR at our center between November 2018 and November 2020. Alexandrite laser hair removal (HR) or diode laser super hair removal (SHR) was performed in 70% and 30% of cases, respectively. Clinical features and daily habits of patients with and without postlaser hypertrichosis were compared.

RESULTS

Of the 7381 patients who received LHR, 25 patients (0.34%) demonstrated an increase in hair growth compared to baseline. Of these 25 patients, 24 had been treated with alexandrite laser HR (P < .01). The most common site was the upper arm, followed by the periareolar area. Daily sun protection was associated with a significantly lower incidence of hypertrichosis (P < .05), as was confirmed and shown to be independent of Fitzpatrick skin type by binary logistic regression analysis (odds ratio = 0.41, P < .05).

CONCLUSIONS

In our clinic, we observed paradoxical hypertrichosis after laser hair removal in a small minority of cases, as described by others. We did not observe differences in incidence related to skin type, but daily sun protection and LHR with diode laser SHR were associated with significant reductions in incidence rates. In addition to previously reported common sites, we also identified the periareolar area as a high-risk region.

Safety of using laser for hair removal in patients with skin diseases: a retrospective study

Laser hair removal is a commonly used method in dermatology which is based on selective thermolysis and utilizes the appropriate wavelength, pulse width, and energy density to damage hair follicles. Given the prevalence of skin diseases such as psoriasis, dermatitis, and vitiligo, and the increasing popularity of laser hair removal, the aim of this study was to investigate the safety of laser hair removal in individuals with skin diseases. This retrospective study was conducted at the laser department of Razi Hospital on 99 patients who underwent laser hair removal. The exacerbation of disease after laser therapy was significantly associated with active skin disease (p = .021) and laser treatment at the site of the disease (p < .001). The incidence of Koebner phenomenon was significantly associated with age (p = .017) and the number of sessions with the ND-YAG device (p = .034). It is crucial to exercise caution when performing laser treatment on individuals with active skin disease and to avoid treating the affected area were possible. If necessary, it is recommended to delay laser treatment until the disease is under control for patients with active skin disease or those who wish to receive laser treatment at the site of the disease.

Paradoxical Hypertrichosis Associated with Laser and Light Therapy for Hair Removal: A Systematic Review and Meta-analysis

BACKGROUND

Paradoxical hypertrichosis (PH) is an uncommon, poorly understood adverse effect associated with laser or intense pulsed light treatment for hair removal.

OBJECTIVE

The objective of this study was to conduct a systematic review and meta-analysis to determine PH prevalence and associated risk factors.

METHODS

We conducted a systematic review and meta-analysis of studies evaluating hair removal with lasers or intense pulsed light. Primary outcome was PH prevalence. Meta-regression and subgroup analysis were used to investigate associations among treatment modality, patients' characteristics, and PH.

RESULTS

Included were 9733 patients in two randomized controlled trials and 20 cohort studies (three prospective and 17 retrospective). Pooled PH prevalence was 3% (95% confidence interval 1-6; I² = 97%). Paradoxical hypertrichosis was associated with a face or neck anatomic location, and occurred in only 0.08% of non-facial/neck cases. Treatment modality and interval between treatments had no effect on the PH rate. There were insufficient data to determine the association between sex and skin type to PH. In three out of four studies, PH gradually improved with continued therapy.

CONCLUSIONS

Based primarily on cohort studies, PH occurs in 3% of patients undergoing hair removal with lasers or intense pulsed light, yet rarely outside the facial/neck areas. Treatment modality does not seem to be a contributing factor. Continuation of treatment in areas with PH may be the most appropriate treatment.

Dermatologic Laser Side Effects and Complications: Prevention and Management

The evolution of modern laser and light-based systems has mirrored the demand for clinically effective treatments and the need for safer technologies with reduced postoperative recovery, side effects, and complications. With each new generation of lasers, more selective tissue destruction can be achieved with reduced unwanted sequelae. Patient selection and preparation, operator technique, and expeditious recognition and management of post-treatment side effects are paramount in avoiding complications and patient dissatisfaction. An overview of important variables to consider for dermatologic laser treatments are presented in order to provide a framework to reduce the severity and duration of possible post-treatment side effects and complications.

810 nm diode laser for hair reduction with Chill-tip technology: prospective observational analysis of 55 patients of Fitzpatrick skin types III, IV,V

Background: Various light based technologies like Diode, long pulsed Nd:Yag and Intense Pulsed Light are used commonly for long-term hair reduction. The commonest indication is hirsutism.Aim: 1. To evaluate efficacy and safety of 810 nm Diode laser in Fitzpatrick skin types III, IV and V.2. To assess percentage of cases on the basis of indications, average number of sessions, fluence required, the long-term results and complications using diode laser in darker skin types.Methods: A prospective observational study of 55 consecutive patients who came for laser hair reduction by 810 nm Light Sheer Diode laser with Chill tip technology was carried out. The sessions were conducted at an interval of 4-6 weeks and the patients were followed up over a period of 2 years. Data was analyzed using software SPSS (Statistical Package for Social Science. Ver.12, Inc. Chicago, USA).Results: Fifty-five patients (51 females and 4 males) were studied. 67.3% (n = 37) had skin type IV. The most common area treated was chin (n = 23). The average growth reduction of terminal hair at the end of three sessions was 61.25%. Only 8% (n = 4) had short-term side effects.Conclusion: Diode laser is highly effective for long-term hair reduction of terminal hair growth in Fitzpatrick skin type III, IV and V with no permanent side effects.Abbreviations: LHR (Laser Hair Reduction).

Evaluation of Laser Effects on the Human Body After Laser Therapy

Lasers have wide applications in the treatment and diagnosis of diseases and various medical fields. Laser therapy like the other methods has advantages and disadvantages. Some risks such as bleeding, pain, and infection are created after laser therapy. Explanation and evaluation of laser effects on cell function, tissue, and the body are the aims of this study. We reviewed papers available from 1986 to 2019 about the effects of lasers on cells and tissue. An online search of PubMed, Science Direct and Google scholar using such keywords as "laser", "cell", "tissue", "body" and "side effects" was performed. The laser photons are absorbed by chromophores, resulting in the target heating and localized damage. Laser irradiation alters cellular metabolism and cellular functions. These alterations may be accompanied by undesired side effects which can be monitored via metabolites level change in the body. Based on this finding, laser therapy may be associated with several side effects and complications; therefore, before treatment, the determination of laser types and their properties is necessary to avoid creating side effects. The advantages and disadvantages of the treatment type should be considered in order to choose the best treatment with the least side effects. The patients' awareness of possible side effects before treatment and also an effective follow-up and management of patients after action are two important points in laser therapy. Training curriculum definition should be determined for laser applicant qualifications in different medical fields.

Evaluation and Treatment of Hirsutism in Premenopausal Women: An Endocrine Society Clinical Practice Guideline

OBJECTIVE

To update the "Evaluation and Treatment of Hirsutism in Premenopausal Women: An Endocrine Society Clinical Practice Guideline," published by the Endocrine Society in 2008.

PARTICIPANTS

The participants include an Endocrine Society-appointed task force of seven medical experts and a methodologist.

EVIDENCE

This evidence-based guideline was developed using the Grading of Recommendations, Assessment, Development, and Evaluation system to describe the strength of recommendations and the quality of evidence. The task force commissioned two systematic reviews and used the best available evidence from other published systematic reviews and individual studies.

CONSENSUS PROCESS

Group meetings, conference calls, and e-mail communications facilitated consensus development. Endocrine Society committees, members, and cosponsoring organizations reviewed and commented on preliminary drafts of the guidelines.

CONCLUSION

We suggest testing for elevated androgen levels in all women with an abnormal hirsutism score. We suggest against testing for elevated androgen levels in eumenorrheic women with unwanted local hair growth (i.e., in the absence of an abnormal hirsutism score). For most women with patient-important hirsutism despite cosmetic measures (shaving, plucking, waxing), we suggest starting with pharmacological therapy and adding direct hair removal methods (electrolysis, photoepilation) for those who desire additional cosmetic benefit. For women with mild hirsutism and no evidence of an endocrine disorder, we suggest either pharmacological therapy or direct hair removal methods. For pharmacological therapy, we suggest oral combined estrogen-progestin contraceptives for the majority of women, adding an antiandrogen after 6 months if the response is suboptimal. We recommend against antiandrogen monotherapy unless adequate contraception is used. We suggest against using insulin-lowering drugs. For most women who choose hair removal therapy, we suggest laser/photoepilation.

Fractional carbon dioxide laser for the treatment of facial atrophic acne scars: prospective clinical trial with short and long-term evaluation

The aim of this study was to evaluate the efficacy and safety of fractional carbon dioxide laser for the treatment of acne scars. Thirty-one participants, 15 female and 16 male, whose mean age was 34.84 ± 10.94 years, were included in this prospective study. The study took place between 2012 and 2016. Participants were evaluated with the "ECCA Grading Scale" before the first session, 3 months (short-term evaluation) and 3 years after the last session (long-term evaluation). Participants received two or three treatment sessions at 4-week intervals, with a 10,600 nm fractional carbon dioxide laser with pulse energies ranging between 100 and 160 mJ, 120 spot type, 75-100 spot/cm² density, and 30 W power. Self-assessments by the participants were done 3 months and 3 years after the last session. The mean ECCA score was 107.90 ± 39.38 before the first session, and 82.17 ± 36.23 at the time of short-term evaluation (p = 0.000). The grade of improvement at the short-term evaluation was as follows: no improvement, mild, moderate, and significant improvement for 7 (22.6%), 11 (35.5%), 9 (29%), and 4 (12.9%) of the participants, respectively. Regarding self-assessments, 80.6 and 61.3% of the participants rated themselves as having at least mild improvement at the short-term and the long-term follow-up periods, respectively. The results of this study suggest that fractional carbon dioxide laser is an efficient treatment option for acne scars. Furthermore, self-assessment results show that more than half of the participants still experience at least mild improvement at the end of 3 years.

Observation of vasculature alternation by intense pulsed light combined with physicochemical methods

Intense pulsed light (IPL) with low energy insufficient to completely destroy a vasculature was applied to rabbit ears to investigate vasculature alteration. Glycerol was combined with IPL to enhance the transfer efficacy of IPL energy. Both trans-illumination and laser speckle contrast images were obtained and analyzed after treatment. The application of IPL and glycerol combination induced vasodilation and improvement in blood flow. Moreover, such phenomenon was maintained over time. IPL may be applied to treat blood circulatory diseases by inducing vasodilation and to improve blood flow.

Efficacy of low-level laser therapy on hair regrowth in dogs with noninflammatory alopecia: a pilot study

BACKGROUND

Canine noninflammatory alopecia (CNA) is a heterogeneous group of skin diseases with different underlying pathogenesis. The therapeutic approach is challenging, and new options for treatment are desirable.

HYPOTHESIS/OBJECTIVES

To test the clinical efficacy of low-level laser therapy (LLLT) on hair regrowth in CNA.

ANIMALS

Seven dogs of different ages, breeds and genders with a clinical and histopathological diagnosis of noninflammatory alopecia.

METHODS

Each dog was treated twice weekly for a maximum of 2 months with a therapeutic laser producing the following three different wavelengths emerging simultaneously from 21 foci: 13 × 16 mW, 470 nm; 4 × 50 mW, 685 nm; and 4 × 200 mW, 830 nm. The fluence given was 3 J/cm(2) , frequency 5 Hz, amplitude of the irradiated area was 25 cm(2) and application time was 1.34 min. A predetermined alopecic area was left untreated and served as a control area. From one dog, post-treatment biopsies of treated and untreated sites were obtained for histological evaluation of hair density and the percentage of haired and nonhaired follicles.

RESULTS

At the end of the study, coat regrowth was greatly improved in six of seven animals and improved in one of seven. By morphometry, the area occupied by hair follicles was 18% in the treated sample and 11% in the untreated one (11%); haired follicles were (per area) 93% in the treated sample and only 9% in the control sample.

CONCLUSIONS AND CLINICAL IMPORTANCE

Our clinical and histological data document promising effects of LLLT on hair regrowth in CNA. Further studies investigating the biological mechanism underlying the effect of LLLT on hair follicle cycling are warranted.

The growth of human scalp hair in females using visible red light laser and LED sources

Background and Objectives

Low level laser (light) therapy (LLLT) has been demonstrated to promote hair growth in males. A double-blind randomized controlled trial was undertaken to define the safety and physiologic effects of LLLT on females with androgenic alopecia.

Methods

Forty-seven females (18–60 years old, Fitzpatrick I–IV, and Ludwig–Savin Baldness Scale I-2, I-3, I-4, II-1, II-2 baldness patterns) were recruited. A transition zone scalp site was selected; hairs were trimmed to 3 mm height; the area was tattooed and photographed. The active group received a “TOPHAT655” unit containing 21, 5 mW diode lasers (655 ± 5 nm) and 30 LEDS (655 ± 20 nm), in a bicycle-helmet like apparatus. The placebo group unit appeared identical, containing incandescent red lights. Patients treated at home every other day × 16 weeks (60 treatments, 67 J/cm² irradiance/25 minute treatment, 2.9 J dose), with follow up and photography at 16 weeks. A masked 2.85 cm² photographic area was evaluated by another blinded investigator. The primary endpoint was the percent increase in hair counts from baseline.

Results

Forty-two patients completed the study (24 active, 18 sham). No adverse events or side effects were reported. Baseline hair counts were 228.2 ± 133.4 (N = 18) in the sham and 209.6 ± 118.5 (N = 24) in the active group (P = 0.642). Post Treatment hair counts were 252.1 ± 143.3 (N = 18) in the sham group and 309.9 ± 166.6 (N = 24) in the active group (P = 0.235). The change in hair counts over baseline was 23.9 ± 30.1 (N = 18) in the sham group and 100.3 ± 53.4 (N = 24) in the active group (P < 0.0001). The percent hair increase over the duration of the study was 11.05 ± 48.30 (N = 18) for the sham group and 48.07 ± 17.61 (N = 24) for the active group (P < 0.001). This demonstrates a 37% increase in hair growth in the active treatment group as compared to the placebo group.

Conclusions

LLLT of the scalp at 655 nm significantly improved hair counts in women with androgenetic alopecia at a rate similar to that observed in males using the same parameters. Lasers Surg. Med. 46:601–607, 2014. © 2014 The Authors. Lasers in Surgery and Medicine published by Wiley Periodicals, Inc.

Tool to visualize and evaluate operator proficiency in laser hair-removal treatments

BACKGROUND

The uniform delivery of laser energy is particularly important for safe and effective laser hair removal (LHR) treatment. Although it is necessary to quantitatively assess the spatial distribution of the delivered laser, laser spots are difficult to trace owing to a lack of visual cues. This study proposes a novel preclinic tool to evaluate operator proficiency in LHR treatment and applies this tool to train novice operators and compare two different treatment techniques (sliding versus spot-by-spot).

METHODS

A simulation bed is constructed to visualize the irradiated laser spots. Six novice operators are recruited to perform four sessions of simulation while changing the treatment techniques and the presence of feedback (sliding without feedback, sliding with feedback, spot-by-spot without feedback, and spot-by-spot with feedback). Laser distribution maps (LDMs) are reconstructed through a series of images processed from the recorded video for each simulation session. Then, an experienced dermatologist classifies the collected LDMs into three different performance groups, which are quantitatively analyzed in terms of four performance indices.

RESULTS

The performance groups are characterized by using a combination of four proposed indices. The best-performing group exhibited the lowest amount of randomness in laser delivery and accurate estimation of mean spot distances. The training was only effective in the sliding treatment technique. After the training, omission errors decreased by 6.32% and better estimation of the mean spot distance of the actual size of the laser-emitting window was achieved. Gels required operators to be trained when the spot-by-spot technique was used, and imposed difficulties in maintaining regular laser delivery when the sliding technique was used.

CONCLUSIONS

Because the proposed system is simple and highly affordable, it is expected to benefit many operators in clinics to train and maintain skilled performance in LHR treatment, which will eventually lead to accomplishing a uniform laser delivery for safe and effective LHR treatment.

Cast application of four weeks' duration significantly affects hair length, diameter and density

BACKGROUND

Localized hypertrichosis following cast application has been recorded, yet no studies characterized these changes systematically.

OBJECTIVE

To evaluate changes of hair length, diameter and density on the legs in patients after cast application.

MATERIALS AND METHODS

Patients with leg injuries and cast application of at least 4 weeks' duration were included in the study. Immediately after cast removal, hair sampling was taken from both legs; cast and control sides. Hair length and diameter were measured by Olympus microscope software. Patients were also analyzed for global changes by three blinded dermatologists.

RESULTS

Fourteen patients, seven of whom were male, were included in this study. On the cast side, both hair length and diameter were significantly greater than the control side (p < 0.001). Subjective evaluations by three blinded dermatologists agreed well with objective measurements and also demonstrated an increase in overall density. Degrees of hair changes did not correlate with the distance from injury sites.

CONCLUSION

Cast application of at least 4 weeks' duration significantly stimulates hair growth in a diffuse pattern. This could possibly lead to novel therapeutic approaches for different types of alopecias.

Laser hair removal: a review

BACKGROUND

Unwanted hair growth is a common aesthetic problem. Laser hair removal has emerged as a leading treatment option for long-term depilation.

OBJECTIVES

To extensively review the literature on laser hair removal pertaining to its theoretical basis, current laser and light-based devices, and their complications. Special treatment recommendations for darker skin types were considered.

MATERIALS AND METHODS

A comprehensive literature search related to the long-pulse alexandrite (755 nm), long-pulse diode (810 nm), long-pulse neodymium-doped yttrium aluminum garnet (Nd:YAG; 1,064 nm), and intense pulsed light (IPL) system, as well as newer home-use devices, was conducted.

RESULTS

The literature supports the use of the alexandrite, diode, Nd:YAG and IPL devices for long-term hair removal. Because of its longer wavelength, the Nd:YAG is the best laser system to use for pigmented skin. Further research is needed regarding the safety and efficacy of home-use devices.

CONCLUSION

Current in-office laser hair removal devices effectively provide a durable solution for unwanted hair removal.

Effects of the 755-nm Alexandrite laser on fine dark facial hair: review of 90 cases

Laser hair removal is a relatively effective method for thick hair. Despite the risk for induction of fine hair growth, application of laser for fine dark hair is sometimes inevitable. We investigate the effects of 755-nm Alexandrite laser on fine dark facial hair and evaluate the induction rates of fine hair growth and case satisfaction. In the present study, the thickening rate of hairs (33.33%) was found to be higher than the previously published rates. However, reduction of hair density can be obtained when the laser sessions are continued.

Successful white hair removal with combined coloring and intense pulsed Light (IPL): a randomized clinical trial

OBJECTIVE

The purpose of this study was to introduce adjunct therapy to intense pulsed light (IPL) and to assess it in terms of safety, expense, feasibility, and efficacy.

BACKGROUND DATA

Currently there is no satisfactory, efficient method for long-term white hair removal.

METHODS

We conducted a randomized clinical trial of hirsute patients with excessive white hair on the chin and cheeks. In addition to IPL, the patients were randomly assigned to have their white hair colored with either black eyeliner or black hair dye as an adjunct to IPL aided for of six sessions (with a 4-week interval between sessions). The primary efficacy outcome, which was defined as the outcome after six sessions of therapy, was scored as poor (<30%), fair (30?60%) or good (>60%) response to white hair removal in predefined areas. The secondary outcome was recurrence 6 months after the final therapy session.

RESULTS

In the eyeliner group (n=31), 15 (48.4%) individuals showed a fair response, and 16 (51.6%) individuals showed a good response. In the color-dye group (n=31), 1 (3.2%), 17 (54.8%) and 13 (41.9%) participants scored poor, fair, and good, respectively. There were no differences in clinician judgment of the treatment success between the eyeliner and color-dye groups after the six therapy sessions (p=0.895). Thirty-one patients had 6 months of visits (11 in the hair dye and 20 in the eyeliner group). Three participants in the color-dye group and five participants in the eyeliner group failed to show improvement 6 months after the laser surgery. There was no distinguishable pattern of failure between the two study groups (p=1).

CONCLUSION

This study supports that hair coloring is an efficient and feasible technique that can be combined with IPL to eliminate white facial hair.

Intense pulsed light (IPL): a review

BACKGROUND

Intense pulsed light (IPL) devices use flashlamps and bandpass filters to emit polychromatic incoherent high-intensity pulsed light of determined wavelength spectrum, fluence, and pulse duration. Similar to lasers, the basic principle of IPL devices is a more or less selective thermal damage of the target. The combination of prescribed wavelengths, fluences, pulse durations, and pulse intervals facilitates the treatment of a wide spectrum of skin conditions.

OBJECTIVE

To summarize the physics of IPL, to provide guidance for the practical use of IPL devices, and to discuss the current literature on IPL in the treatment of unwanted hair growth, vascular lesions, pigmented lesions, acne vulgaris, and photodamaged skin and as a light source for PDT and skin rejuvenation.

METHODS

A systematic search of several electronic databases, including Medline and PubMed and the authors experience on intense pulsed light.

RESULTS

Numerous trials show the effectiveness and compatibility of IPL devices.

CONCLUSION

Most comparative trials attest IPLs similar effectiveness to lasers (level of evidence: 2b to 4, depending on the indication). However, large controlled and blinded comparative trials with an extended follow-up period are necessary.

Nurse-administered laser in dermatology

Nurses have become an essential part of patient care in laser therapy. In dermatology, the potential for helping patients achieve excellent results for individual skin needs is exponential when combined with appropriate technology, evidence-based care, and a competent, conscientious nurse. This article explains how a laser functions, outlines the use of lasers in treating particular dermatologic conditions, provides guidelines for posttreatment care, and discusses the nurse's role in providing laser treatment.