intense pulsed light

Intense pulsed light is the use of intense pulses of non-coherent light over a range of wavelengths from approximately 500 nm to approximately 1200 nm.{{cite web|title=Intense Pulsed Light Systems|url=http://www.palomarmedical.com/uploaddocs/intense-pulsed-light-systems.pdf|archive-url=https://web.archive.org/web/20101127221735/http://palomarmedical.com/uploadDocs/Intense-Pulsed-Light-Systems.pdf|url-status=dead|archive-date=27 November 2010|publisher=HMP Communications|access-date=2 August 2012}} Linear Xenon flashlamps produce high output bursts of broad spectrum. The flashlamp is typically cooled by water flow in a glass tube concentric with the flashlamp. In addition to its cooling of the flashlamp, the water envelope also filters out longer wavelength infrared light that is heavily absorbed in water and could damage the patient's skin that has a high concentration of water. Light generated by the flashlamp is typically coupled to the skin by cooled (in many cases) lightguides which are also used to protect the skin in contact with the device.{{Cite book|last=Lahiri|first=Koushik|url=https://books.google.com/books?id=-HKJDAAAQBAJ&q=Xenon%20flash%20lamps%20produce%20high%20output%20bursts%20of%20broad%20spectrum.%20Cooling%20is%20used%20to%20protect%20the%20skin%20in%20contact%20with%20the%20device.&pg=PA54|title=Textbook of Lasers in Dermatology|date=2016-07-30|publisher=JP Medical Ltd|isbn=978-93-85999-62-8|language=en}}

Regulations governing IPL vary by jurisdiction.{{cite web|title=Laser Information |url=http://www.doh.state.fl.us/MQA/medical/me_laser.html |publisher=Florida Department of Health |access-date=2 August 2012 |url-status=dead |archive-url=https://web.archive.org/web/20121104061415/http://www.doh.state.fl.us/mqa/medical/me_laser.html |archive-date=November 4, 2012 }}{{Better source needed|date=March 2020}} A distinction is sometimes made{{By whom|date=March 2020}} between beauty-grade and medical-grade machines, mainly to get around regulations.

IPL was invented in 1992 by Shimon Eckhouse who wrote the first patent describing the technology in detail (US patent No. 5,405,368 filed in 1992 and granted in 1995). The first medical use of IPL was aimed at the treatment of vascular lesions and introduced to the medical market by ESC Medical which was founded by Shimon Eckhouse to develop and commercialize the technology. The first FDA approval of IPL for treatment of vascular lesions was granted to ESC Medical in 1995 with additional FDA clearances for treatment of pigmented lesions and hair removal granted in 1996 and 1997 respectively. Use quickly spread to a variety of medical and cosmetic settings.{{Cite journal|last=Goldberg|first=David J.|date=June 2012|title=Current Trends in Intense Pulsed Light|journal=The Journal of Clinical and Aesthetic Dermatology|volume=5|issue=6|pages=45–53|issn=1941-2789|pmc=3390232|pmid=22768357}} Treatment is generally safe and effective, but complications can occur, such as hyperpigmentation.{{Cite journal|title = Current Trends in Intense Pulsed Light|date = Jun 2012|journal = Clin Aesthet Dermatol.}} The polychromatic light can reach multiple chromophores in human skin: mainly hemoglobin, water, and melanin.{{Cite journal|last1=Tseng|first1=Sheng-Hao|last2=Bargo|first2=Paulo|last3=Durkin|first3=Anthony|last4=Kollias|first4=Nikiforos|date=2009-08-17|title=Chromophore concentrations, absorption and scattering properties of human skin in-vivo|journal=Optics Express|volume=17|issue=17|pages=14599–14617|doi=10.1364/oe.17.014599|issn=1094-4087|pmc=2754563|pmid=19687939|bibcode=2009OExpr..1714599T}} This results in selective photothermolysis of blood vessels, pigmented cells, or hair follicles.{{Citation needed|date=March 2020}}

IPL can reduce hair growth, most effectively in darker, coarser hair.{{Cite news|last=Campbell|first=Leigh|url=https://www.huffingtonpost.com.au/2016/01/07/laser-hair-removal_n_8925010.html|title=The Difference Between Laser And IPL For Permanent Hair Removal|date=2016-01-07|work=Huffington Post|access-date=2020-03-17|language=en-AU}} IPL is distinct from laser hair removal which uses coherent monochromatic laser light.{{Cite news|last=Young|first=Katy|url=https://www.telegraph.co.uk/beauty/skin/does-ipl-hair-removal-really-work/|title=Does IPL hair removal really work?|date=2018-04-11|work=The Telegraph|access-date=2020-03-17|language=en-GB|issn=0307-1235}}

Broad-spectrum light is applied to the surface of the skin, targeting melanin. This light travels through the skin until it strikes the hair shafts or hair follicle.{{Cite journal|last1=Husain|first1=Zain|last2=Alster|first2=Tina S|date=2016-02-04|title=The role of lasers and intense pulsed light technology in dermatology|journal=Clinical, Cosmetic and Investigational Dermatology|volume=9|pages=29–40|doi=10.2147/CCID.S69106|issn=1178-7015|pmc=4745852|pmid=26893574 |doi-access=free }} The follicle is usually where the highest concentration of melanin is located. As the light is absorbed, the bulb and most of the hair shaft are heated, destroying the hair-producing papilla. It is also claimed that heat conversion occurs directly in the darker capillaries that bring blood to the follicle.{{Cite book|last=Lahiri|first=Koushik|url=https://books.google.com/books?id=-HKJDAAAQBAJ&q=The%20area%20to%20be%20treated%20should%20be%20clean%20shaven%20and%20free%20of%20sunburn.%20IPL&pg=PA55|title=Textbook of Lasers in Dermatology|date=2016-07-30|publisher=JP Medical Ltd|isbn=978-93-85999-62-8|pages=55|language=en}}

At any one time, not all hair follicles are 'active', and only active hair follicles can be affected by the treatment. 'Inactive' hair follicles can be treated as they become 'active' over time.{{Citation needed|date=March 2020}} For IPL treatments, an average of 8–10 treatments, 4–6 weeks apart, are required to remove most visible hair.

There is no common treatment protocol, as it depends on the equipment used and patient skin type. The area to be treated should be clean shaven and free of sunburn.{{Cite book|last=Lahiri|first=Koushik|url=https://books.google.com/books?id=-HKJDAAAQBAJ&q=The%20area%20to%20be%20treated%20should%20be%20clean%20shaven%20and%20free%20of%20sunburn.%20IPL&pg=PA55|title=Textbook of Lasers in Dermatology|date=2016-07-30|publisher=JP Medical Ltd|isbn=978-93-85999-62-8|language=en}}

Although IPL treatments will permanently reduce the total number of body hairs, they will not result in a permanent removal of all hair.{{cite journal|last=Klein|first=A.|author2=Steinert, S. |title=Photoepilation with a diode laser vs. intense pulsed light (IPL): a randomized, intra-patient left-to-right trial|journal=British Journal of Dermatology|volume=168|issue=6|date=1 December 2012| pages=1287–93| doi=10.1111/bjd.12182|pmid=23278132|last3=Baeumler| first3=W. |last4=Landthaler|first4=M.|last5=Babilas|first5=P.|s2cid=8889666}}

Certain skin conditions, health irregularities, and medications can impact whether it is safe for a person to receive a light-based hair removal treatment.{{Citation needed|date=March 2020}} Photo-sensitizing medications, or damage to the skin are contraindications to treatment. According to Remington, manufacturer of an IPL device, all IPL and laser devices should only be used on light to medium skin tones, and work best on darker hair.{{cite web|url=http://uk.remington-europe.com/microsites/ilight-pro/dr-kubicka-i-light-ask-the-expert/|title=Trends & Tips - Remington|website=uk.remington-europe.com}}

In August 1997, IPL was reported to have permanently removed terminal hair in two patients who underwent multiple treatments to their beards. In October of that year, the first IPL system developed for hair removal and resulted in 60% hair reduction after 12 weeks.{{cite journal|last1=Gold|first1=Michael H.|title=Long-term epilation using the EpiLight broad band, intense pulsed light Hair Removal System|journal=Dermatologic Surgery|date=October 1997|volume=23|issue=10|pages=909–913|doi=10.1111/j.1524-4725.1997.tb00746.x|pmid=9357500|last2=Bell|first2=Michael W.|last3=Foster|first3=Teresa D.|last4=Street|first4=Sherri|s2cid=25398697}}

It is important to note that these studies utilized a variety of IPL devices on patients with various hair types, skin types, and targeted skin areas. Thus the results are not directly comparable.

According to the FDA, permanent hair reduction means the "long-term, stable reduction in the number of hairs regrowing after a treatment regime." In other words, the number of hairs regrowing must be consistently greater than the duration of the complete growth cycle of hair follicles, which varies from four to twelve months by body location.{{cite web|url=https://www.fda.gov/radiation-emittingproducts/resourcesforyouradiationemittingproducts/ucm252761.htm#1 |title=Laser Facts |publisher=FDA |access-date=23 September 2014 |url-status=dead |archive-url=https://web.archive.org/web/20140912203435/https://www.fda.gov/Radiation-EmittingProducts/ResourcesforYouRadiationEmittingProducts/ucm252761.htm |archive-date=September 12, 2014 }} IPL has been found to be much less effective than laser hair removal; however, many patients experience satisfaction with significant hair reduction.

A 2006 article in the journal Lasers in Medical Science compared IPL and both alexandrite and diode lasers. The review found no statistical difference in effectiveness, but a higher incidence of side effects with diode laser treatment. Hair reduction after six months was reported as 68.75% for alexandrite lasers, 71.71% for diode lasers, and 66.96% for IPL. Side effects were reported as 9.5% for alexandrite lasers, 28.9% for diode lasers, and 15.3% for IPL. All side effects were found to be temporary and even pigmentation changes returned to normal within six months.{{cite journal|last1 = Toosi|first1 = Parviz|title = A comparison study of the efficacy and side effects of different light sources in hair removal|journal = Lasers in Medical Science|date = April 2006|volume = 21|issue = 1|pages = 1–4|doi = 10.1007/s10103-006-0373-2|pmid = 16583183|last2 = Sadighha|first2 = Afshin|last3 = Sharifian|first3 = Ali|last4 = Razavi|first4 = Gita Meshkat|s2cid = 10093379}}

A 2009 study evaluated the rate of hair removal after a second generation IPL source. Results found that patients had 75% hair reduction after four months, and up to 80% after eight months.{{cite journal|last=Smith|first=S.R.|author2=Y. Tse|author3=S.K. Adsit|display-authors=etal|year=1998|title=Long-term results of hair photo-epilation|journal=Lasers Surg Med|page=43}}{{cite journal|last=Troilus|first=A.|author2=Troilus C|date=September 1999|title=Hair removal with a second generation broad spectrum intense pulsed light source—a long term follow-up|journal=J Cutan Laser Ther|volume=1|issue=3|pages=173–178|doi=10.1080/14628839950516832|pmid=11360414}}

{{Expand section|date=June 2012}}

IPL was first developed for vascular conditions. It is at least as effective as pulsed dye lasers and can penetrate deeper with reduced risk of purpura and hyperpigmentation. IPL can also be used for the treatment of dry eye conditions such as meibomian gland dysfunction.{{cite web|url=http://www.aao.org/publications/eyenet/201207/upload/july-2012-clinical-update-cornea.pdf |title=Managing Blepharitis:Tried-and-True and New Approaches |author=Annie Stuart |date=July 2012 |publisher=EyeNet |access-date=February 22, 2015 |url-status=dead |archive-url=https://web.archive.org/web/20150305165437/http://www.aao.org/publications/eyenet/201207/upload/July-2012-Clinical-Update-Cornea.pdf |archive-date=March 5, 2015 }}{{cite web|url=http://www.aao.org/pdf/aaosub_cornea_2012_syllabus.pdf |title=Pushing Surgical Boundaries, Professional Development, and Popular Opinion |last1=Aldave |first1=Anthony J. |last2=Afshari |first2=Natalie |last3=Colby |first3=Kathryn |date=10 November 2012 |publisher=The American Academy of Ophthalmology |access-date=February 22, 2015 |url-status=dead |archive-url=https://web.archive.org/web/20130123230629/http://www.aao.org/pdf/AAOSub_Cornea_2012_Syllabus.pdf |archive-date=January 23, 2013 }} IPL can treat pigmented lesions with rapid recovery. Dyschromia can be cleared after repeated sessions. Photoaging treatment has been explored. A series of IPL can be used for facial rejuvenation, improving skin laxity and collagen production. IPL combined with facial injections can be used for dynamic rhytids. Home IPL devices have been developed.

IPL is employed in the treatment of a range of dermatological conditions including photodamage induced dyspigmentation and vascular changes, poikiloderma of Civatte, rosacea, acne vulgaris, sebaceous gland hyperplasia, broken capillaries, telangiectases, vascular lesions (small blood vessels), pigmented lesions (freckles, liver spots, birth marks ), melasma, actinic keratosis, photorejuvenation, basal cell carcinoma, and Bowen's disease (squamous cell carcinoma).{{Cite journal|title = Application of intense pulsed light in the treatment of dermatologic disease: a systematic review.|date = Apr 2014|journal = Dermatol. Surg.|doi = 10.1111/dsu.12424|pmid = 24495252 |volume=40 |issue = 4|pages=359–77|last1 = Wat|first1 = Heidi|last2 = Wu|first2 = Douglas C.|last3 = Rao|first3 = Jaggi|last4 = Goldman|first4 = Mitchel P.|s2cid = 205081994}}

• Electrology

{{Reflist}}

• {{cite journal |vauthors=Husain Z, Alster TS |title=The role of lasers and intense pulsed light technology in dermatology |journal=Clinical, Cosmetic and Investigational Dermatology |volume=9 |pages=29–40 |date=2016 |pmid=26893574 |pmc=4745852 |doi=10.2147/CCID.S69106 |type=Review |doi-access=free }}

{{Cosmetics}}

{{Human hair}}

{{DEFAULTSORT:Intense Pulsed Light}}

Category:Hair removal