SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Hair removal

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Studies on bimatoprost were performed with two objectives: (i) to determine whether bimatoprost possesses hair growth-stimulating properties beyond eyelash hypertrichosis and (ii) to investigate the biodisposition of bimatoprost in skin for the first time. Bimatoprost, at the dose used clinically for eyelash growth (0.03%) and given once daily for 14 days, increased pelage hair growth in C57/black 6 mice. This occurred as a much earlier onset of new hair growth in shaved mice and the time taken to achieve complete hair regrowth, according to photographic documentation and visual assessment. Bimatoprost biodisposition in the skin was determined at three concentrations: 0.01%, 0.03% and 0.06%. Dose-dependent C(max) values were obtained (3.41, 6.74, 12.3 μg/g tissue), and cutaneous bimatoprost was well maintained for 24 h following a single dose. Bimatoprost was recovered from the skin only as the intact molecule, with no detectable levels of metabolites. Thus, bimatoprost produces hypertrichosis as the intact molecule.

Concepts: Skin, Tissue, According to Jim, Mouse, Hair follicle, Keratin, Facial hair, Hair removal

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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.

Concepts: Light, Hirsutism, Yttrium aluminium garnet, Intense pulsed light, Hair removal, Laser hair removal, Depilation, Electrology

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Fox-Fordyce disease is an uncommon inflammatory disease of the apocrine sweat glands. Two recent reports indicated laser hair removal as a novel cause of axillary Fox-Fordyce disease. We report the first case of Fox-Fordyce disease developing in women after completing treatment with a depilatory hair laser appearing in the axillae, umbilicus, and pubis. We describe a case of Fox-Fordyce disease that developed in a 27-year-old woman 3 months after she had completed two LightSheer Diode laser treatments of her axilla, periumbilical region, and bikini area. Clinical and histopathological changes are as well detailed. Laser therapy induces damage to follicular infundibulum, resulting in altered maturation of keratinocytes which led to keratin plugging causing the common pathologic features in Fox-Fordyce disease. Differences in the physiologic features of the anatomic sites, in the susceptibility to laser-induced injury among these areas, or additional factors may contribute to Fox-Fordyce disease.

Concepts: Medicine, Laser, Laser medicine, Sweat gland, Axilla, Hair removal, Laser hair removal, Electrology

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The purpose of our study was to verify the results of the association of Q-switched Nd: YAG non-ablative fractionated with intense pulsed light, in order to treat patients with refractory melasma. The combination of these two devices seems to be the best treatment to combat hyperpigmentation produced by melasma, with low occurrence of side effects, which may be justified by the selective photothermolysis at subcellular level.

Concepts: Laser, The Association, Intense pulsed light, Hair removal, Depilation

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The Italian Society of Colorectal Surgery (SICCR.) has prepared clinical practice guidelines to help its members to optimize the treatment of pilonidal disease, a very common condition, especially among young people, and therefore of great importance on a socioeconomic level. The SICCR committee of experts on pilonidal disease analyzed the international literature and evaluated current evidence. Nonoperative management includes gluteal cleft shaving, laser epilation as well as fibrin glue and phenol injection: reported healing rates and recurrence incidence are satisfactory but the majority of studies are small series with low-quality evidence. Surgical therapy which can be divided into two categories: excision of diseased tissue with primary closure using different techniques or excision with healing by secondary intention. On the whole, no clear benefit is demonstrated for one technique over the other.

Concepts: Medicine, Epidemiology, Surgery, Laser, Plastic surgery, Prevalence, Excision, Hair removal

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Traction alopecia is hair loss that occurs after persistent pulling (e.g., during cosmetic procedures) on the roots of hair over time. Unlike plucking, which is painful, persistent pulling may go unnoticed until a patient presents with either bald spots or diffuse telogen shedding. Each hair follicle in the scalp contains an arrector pili muscle that, when contracted, erects the hair. The smooth muscle in the arrector pili expresses α1 adrenergic receptors (α1 -AR). As such, we hypothesized that contraction of the arrector pili muscle via an α1 -AR agonist would increase the threshold of force required to pluck hair during cosmetic procedures. Female subjects, ages 18-40, were recruited to study the effect of topically applied phenylephrine, a selective α1 -AR agonist, on epilation force and hair shedding during cosmetic procedures. In our blinded study, 80% of subjects demonstrated reduced shedding on days using phenylephrine compared to days using a placebo solution. The average reduction in hair loss was approximately 42%. In addition, the force threshold required for epilation increased by approximately 172% following topical phenylephrine application. To our knowledge this is the first study demonstrating the utility of α1 -AR agonists in the treatment of traction alopecia and hair shedding during cosmetic procedures.

Concepts: Pharmacology, Chemotherapy, Agonist, Adrenergic receptor, Alopecia, Baldness, Hair removal, Traction alopecia

2

Ocular tissues are known to be sensitive to damage from exposure to laser emissions. This study reports the case of a female patient with acute unilateral anterior uveitis caused by alexandrite laser-assisted hair removal of the eyebrows. We report a 38-year-old female who presented with unilateral eye pain, redness, and photophobia after receiving alexandrite (755 nm) laser epilation of both eyebrows. Best corrected visual acuity was 20/20 in both eyes. Right eye examination was normal. Left eye examination showed conjunctival injection and 2+/3+ cells in the anterior chamber. Intraocular pressure and fundus examination were normal. Topical steroids and cycloplegic drops were prescribed for 3 weeks. At the end of the 3-week follow-up, best corrected visual acuity was 20/20, and intraocular pressure and fundus examination were normal in both eyes. The left eye was white, and the anterior chamber was clear. The patient continues to be monitored. In conclusion, without adequate protective eyewear, laser hair removal of the eyebrows with alexandrite laser can lead to ocular damage.

Concepts: Laser, Eye, Visual acuity, Ophthalmology, Waxing, Hair removal, Laser hair removal, Electrology

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One underreported, rare side effect of laser hair removal, is paradoxical hypertrichosis. It is largely unknown what the long-term outcomes are of patients who develop this complication. We report a 21-year-old, Fitzpatrick II, male patient, who had patchy areas of dark hair affecting various body areas. An Alexandrite 755 nm laser was used to address the desired areas at energies between 20-22 J/cm(2) at 10-12 week intervals over a course of 7 treatments. After 3 treatments, the patient noted a significant increase in the density and length of hairs involving the back, shoulders, neck and upper arms. The patient was followed on a bi-annual basis, without further epilatory intervention. After 10 years, the areas of paradoxical hair growth were sparser compared to immediate post-treatment but remained denser compared to pre-treatment. This case illustrates improvement in the condition over time without intervention. Further studies are needed to determine the etiopathogenesis of this phenomenon.

Concepts: Time, Patient, Term, Laser medicine, Hair removal, Laser hair removal, Depilation, Electrology

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Poly cystic ovarian syndrome (PCOS) has been described as the common diagnosis for hirsutism in women. Facial hirsutism is by far the most distressing symptom of hyperandrogenism in women with PCOS. A statistically significant improvement in psychological well-being has been reported in patients with PCOS allocated for laser-assisted hair removal. The theory of selective photothermolysis has revolutionised laser hair removal in that it is effective and safe, when operated by sufficiently trained and experienced professionals. Long-pulsed ruby (694nm), long-pulsed alexandrite (755nm), Diode (800-980nm), long-pulsed Nd:YAG (1064nm) are commercially available laser devices for hair removal most widely studied. This article will introduce the fundamentals and mechanism of action of lasers in hair removal, in a contemporary literature review looking at medium to long term efficacy and safety profiles of various laser hair removal modalities most widely commercially available to date.

Concepts: Laser, Polycystic ovary syndrome, Hirsutism, Laser medicine, Hair removal, Laser hair removal, Depilation, Electrology

0

Unwanted facial and body hair presents as a common finding in many patients, such as females with hirsutism. With advances in laser and light technology, a clinically significant reduction in hair can be achieved in patients with light skin. However, in patients with darker skin, Fitzpatrick skin types (FST) IV-VI, the higher melanin content of the skin interferes with the proposed mechanism of laser-induced selective photothermolysis, which is to target the melanin in the hair follicle to cause permanent destruction of hair bulge stem cells. Many prospective and retrospective studies have been conducted with laser and light hair-removal devices, but most exclude patients with darkly pigmented skin, considering them a high-risk group for unwanted side effects, including pigmentation changes, blisters, and crust formation. We reviewed the published literature to obtain studies that focused on hair reduction for darker skin types. The existing literature for this patient population identifies longer wavelengths as a key element of the treatment protocol and indicates neodymium-doped yttrium aluminum garnet (Nd:YAG), diode, alexandrite, and ruby lasers as well as certain intense pulsed light sources for safe hair reduction with minimal side effects in patients with FST IV-VI, so long as energy settings and wavelengths are appropriate. Based on the findings in this review, safe and effective hair reduction for patients with FST IV-VI is achievable under proper treatment protocols and energy settings.

Concepts: Quantum mechanics, Light, Laser, Skin, Hair, Hair follicle, Human skin color, Hair removal