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Laser hack of self-driving cars can ‘delete’ pedestrians

<p>Although a city filled with entirely self-driving cars is still in the realm of science fiction, more and more cars are <a href="https://en.wikipedia.org/wiki/Tesla_Autopilot" target="_blank" rel="noopener">coming with ‘self-driving’ features so</a> it’s a little alarming to learn that there are ways to use lasers to mess with the technology the cars use to detect its surroundings.</p> <p><a href="https://arxiv.org/abs/2210.09482" target="_blank" rel="noopener">In a study uploaded to arXiv</a> by a team of researchers in the US and Japan, researchers were able to trick the ‘victim vehicle’ (their words not ours) into not seeing a pedestrian or other object in its way.</p> <p>Most self-driving cars use LIDAR to be able to ‘see’ around them by sending out a laser light and then recording the reflection from objects in the area. The time it takes for the light to reflect back gives the system information about how far away the object is.</p> <p>This new ‘hack’ or spoof works because a perfectly timed laser shined onto a LIDAR system can create a blind spot large enough to hide an object like a pedestrian.</p> <p>“We mimic the LIDAR reflections with our laser to make the sensor discount other reflections that are coming in from genuine obstacles,” <a href="https://www.eurekalert.org/news-releases/969698" target="_blank" rel="noopener">said University of Florida cyber security researcher professor Sara Rampazzi.</a></p> <p>“The LIDAR is still receiving genuine data from the obstacle, but the data are automatically discarded because our fake reflections are the only one perceived by the sensor.”</p> <div class="newsletter-box"> <div id="wpcf7-f6-p221287-o1" class="wpcf7" dir="ltr" lang="en-US" role="form"> </div> </div> <p>Although the technology is relatively simple, the attack isn’t an easy one. The team demonstrated the attack up to 10 meters away from the car, but the device must be perfectly timed, and move with the car to be able to keep the laser pointing the right way.</p> <p>The researchers have already told manufacturers about this potential exploit and have suggested ways to be able to minimise the problem. Manufacturers might be able to teach the software to look for the tell-tale signatures of the spoofed reflections added by the laser attack.</p> <p>“Revealing this liability allows us to build a more reliable system,” <a href="https://www.eurekalert.org/news-releases/969698" target="_blank" rel="noopener">said first author, University of Michigan computer scientist Yulong Cao.</a></p> <p>“In our paper, we demonstrate that previous defence strategies aren’t enough, and we propose modifications that should address this weakness.”</p> <p>This unfortunately isn’t the first time that researchers have found <a href="https://cosmosmagazine.com/news/tricking-driverless-car-sensors/" target="_blank" rel="noreferrer noopener">vulnerabilities with LIDAR sensors on self-driving cars</a>, but as more of these problems are uncovered and fixed, the technology will hopefully end up safer in the long run.</p> <p>The research is to be presented next year at the <a href="https://www.usenix.org/conference/usenixsecurity23" target="_blank" rel="noopener">2023 USENIX Security Symposium</a>.</p> <p><img id="cosmos-post-tracker" style="opacity: 0; height: 1px!important; width: 1px!important; border: 0!important; position: absolute!important; z-index: -1!important;" src="https://syndication.cosmosmagazine.com/?id=221287&amp;title=Laser+hack+of+self-driving+cars+can+%E2%80%98delete%E2%80%99+pedestrians" width="1" height="1" /></p> <div id="contributors"> <p><em><a href="https://cosmosmagazine.com/technology/laser-hack-lidar-self-driving-cars-delete-pedestrians/" target="_blank" rel="noopener">This article</a> was originally published on Cosmos Magazine and was written by Jacinta Bowler.</em></p> <p><em>Image: Getty Images</em></p> </div>

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When laser surgery turns into a nightmare

<p>It will soon be a year since Jessica Starr, a popular weatherperson on Detroit TV, took her own life. Her husband said she did so because of complications related to <a href="https://www.today.com/health/smile-surgery-husband-meteorologist-who-took-her-own-life-speaks-t151062">her recent laser refractive surgery</a>.</p> <p>Such complications are not as rare as people think. <a href="https://www.nytimes.com/2018/06/11/well/lasik-complications-vision.html">The <em>New York Times</em></a> warned in 2018 of the potential effects on some patients. More recently, and closer to home, <a href="https://www.ctvnews.ca/health/lasik-md-patients-allege-nerve-damage-file-class-action-lawsuit-1.4697069">a class-action lawsuit was filed across the country</a> against Québéc-based company Lasik MD. It is accused of failing to properly warn its clients of the risks associated with vision correction surgery.</p> <p>Does this mean that the dream of getting rid of glasses while still improving vision should be forgotten?</p> <p><strong>Improved technology</strong></p> <p>Refractive laser surgery aims to change the profile of the cornea, the front and clear part of the eye, to correct common vision problems: nearsightedness, farsightedness and astigmatism. The idea is to eliminate the need for glasses.</p> <p>Introduced in 1983 in Germany, the first North American procedure <a href="https://www.ncbi.nlm.nih.gov/pubmed/?term=kugler+wang+laser+applied+optics">was performed in 1985</a>. Since then, millions have been done. At that time, laser surgery was an advantageous alternative to <a href="https://www.ncbi.nlm.nih.gov/pubmed/2686058">a more imprecise technique, radial keratotomy </a>(KR).</p> <p>The first laser technologies led to better, more stable, and more predictable results, but they were also associated <a href="https://www.ncbi.nlm.nih.gov/pubmed/31819355">with a number of complications</a>: intense pain during the procedure and in the days that followed, off-centre treatment leading to the perception of halos and glare, under- or over-correction requiring the need for retouching or a return to wearing glasses, permanent corneal fog or delayed healing of the corneal surface with increased potential for infection.</p> <p>In order to improve this profile, and especially the patient’s comfort, a technique called LASIK (laser <em>in situ</em> keratomileusis) was developed in the 1990s. This time, the laser is applied once a flap of tissue, generated by incising the cornea with a small planer equipped with a blade, is lifted. The flap is then replaced without the need for sutures.</p> <p><strong>Complications remain</strong></p> <p>All surgery carries risks. Serious incidents after <a href="https://www.newswire.ca/news-releases/protegez-vous-fevrier-2016---la-chirurgie-des-yeux-au-laser-sous-enquete-565633031.html">LASIK occur in only 0.1 per cent of cases</a>. But various complications affect between 10 and 30 per cent of patients undergoing surgery, compared to 7.7 per cent <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3777802/">after cataract surgery</a>.</p> <p>While the majority of complications are minor and do not result in permanent consequences, a number of patients experience chronic, severe post-operative pain and/or visual problems, to the point where Morris Waxler, a former Food and Drug Administration expert, <a href="https://www.cbsnews.com/news/lasik-eye-surgery-retired-fda-adviser-says-procedure-should-be-taken-off-market/">is calling for a recall and suspension of its use pending further safety investigations</a>.</p> <p>Regarding LASIK, <a href="https://www.canada.ca/en/health-canada/services/medical-procedures/laser-eye-surgery.html">Health Canada lists several potentially serious effects</a> that must be taken into account.</p> <p><strong>A nightmare case</strong></p> <p>Following laser surgery, the cornea is traumatized and must recover to restore normal function. In the case of LASIK, the cornea is cut at the level of the sensory nerves. These nerves protect the eye but also provide the feedback (biofeedback) necessary for the production of new tears.</p> <p>In the absence of this feedback, the eye dries out and its surface can deteriorate. In the majority of cases, the cut nerves will return to normal function within four to six months. But for a number of patients, the episode turns into a nightmare.</p> <p>Karen (not her real name) is one such patient I recently met. As a young, dynamic executive, she had opted for surgery for practical (work, sports activities) and esthetic reasons. Attracted by promotions and a tempting price, she went to a laser centre and was quickly examined by the staff. Even more quickly, she was given an appointment for surgery — the next day! Without thinking too much, she proceeded.</p> <p>In the days and weeks that followed, her eyes began to hurt more and more —intense pain that felt like knives in her eyes, redness and sensitivity to light requiring her to wear sunglasses even indoors. She had difficulty sleeping.</p> <p>The staff at the centre tried to reassure her, saying it would be temporary, that she is the only one to whom this happened, and that it would heal by itself. Weeks went by, without improvement. She asked to see the surgeon again.</p> <p>The surgeon told her that her eye was healed and that nothing more could be done for her. His tone and attitude left Karen in great despair. She had feelings of rejection, of denial of what she was experiencing, of incomprehension. The situation affected her work. She began to consult other professionals, always being told that her eyes were perfect. No one seemed to understand.</p> <p><strong>A puzzling condition</strong></p> <p>Karen actually suffers from neuropathy. It is a disorder of the peripheral nerves that causes symptoms but is not associated with any visible pathology. Following LASIK, the nerves in the cornea remain permanently damaged, like bare electrical wires, or they regenerate but make poor connections. In either case, the nerves send a constant signal of pain to the brain.</p> <p>After a few weeks/months, the pain becomes internalized (like pain emanating from a phantom limb) and the brain is therefore involved in making the symptoms chronic. Because no one really understands this condition, patients are dismissed and depression sets in as the condition worsens.</p> <p>The lack of understanding of this case stems from the fact that it is a new field in ocular medicine that is poorly documented in the scientific literature. Treatments are complex and time-consuming. It is, in fact, necessary to create new normal nerve connections while breaking the bad ones, using medication such as cortisone, drops of autologous serum and dressing lenses made of amniotic membrane, etc.</p> <p>The internalized stimulation must also be addressed, using oral medication prescribed by a specialized pain clinic. Antidepressants may also be helpful, but they usually have the effect of increasing dryness of the eyes, which is counterproductive. Psychotherapy is essential, with a professional trained in the treatment of chronic pain. Cannabis oil could help, in theory, but <a href="https://www.ncbi.nlm.nih.gov/pubmed/29513392">this approach is controversial</a>.</p> <p>Karen lost her job due to frequent absenteeism and loss of productivity. Her treatments are expensive and are eating into her savings. The financial stress increases as the months go by and the light at the end of the tunnel is not always clear. The situation put great pressure on her marriage and her spouse has found it difficult to cope with the circumstances.</p> <h2>What to know before deciding to have surgery</h2> <p>To avoid an outcome like Karen’s, certain precautions can be taken.</p> <p>First of all, it’s best to avoid making decisions on a whim. Get information from your own eye-care professional, the one who has known your eyes for a long time. Then, get at least two opinions — in different centres — before proceeding, and assess those interactions and the level of trust you feel.</p> <p>Certain risk factors can reduce the effectiveness of the procedure. For example, many patients opt for surgery because they become intolerant to contact lenses, with uncomfortable and dry eyes at the end of the day. If this is the case, it is because the eye is already prone to dryness and surgery will only increase it. It is therefore necessary to consult your optometrist in order to treat this dryness <em>before</em> the operation, and wait until the surface of the eye is ready for surgery.</p> <p>Patients with chronic inflammatory diseases should avoid refractive surgery. These diseases include fibromyalgia, irritable bowel syndrome, Crohn’s disease, lupus and rheumatoid arthritis. Similarly, people with diabetes or severe and chronic migraines <a href="https://www.aafp.org/afp/2017/0515/p637.html">are considered poor candidates</a>. Finally, <a href="https://www.ncbi.nlm.nih.gov/pubmed/22081153">people with obsessive-compulsive disorders should also abstain</a>. For example, they may have the reflex to rub their eyes violently, which can dislodge the tissue flap.</p> <p>Patients with severe myopia (&gt;8D) as well as patients with large pupils (black part of the eye larger than five millimetres) are prone to the continuous perception of halos and glare after surgery.</p> <p><strong>After the operation</strong></p> <p>Once the operation has been performed, it’s important to ensure adequate professional followup. Demand to see an optometrist or ophthalmologist at every opportunity. Assistance personnel, even properly trained, are not legally authorized to diagnose your condition (saying that everything is fine is a diagnosis in itself).</p> <p>It’s also important to never neglect regular eye health checkups. A severely near-sighted person, even after surgery, is still at risk of having a torn retina.</p> <p>Laser surgery is performed successfully in more than 95 per cent of cases. To avoid chronic problems, it is important to be well assessed and well informed.</p> <p>You only have two eyes and they are not replaceable. So take every precaution to ensure laser surgery is safe for you.<!-- Below is The Conversation's page counter tag. Please DO NOT REMOVE. --><img style="border: none !important; box-shadow: none !important; margin: 0 !important; max-height: 1px !important; max-width: 1px !important; min-height: 1px !important; min-width: 1px !important; opacity: 0 !important; outline: none !important; padding: 0 !important; text-shadow: none !important;" src="https://counter.theconversation.com/content/130518/count.gif?distributor=republish-lightbox-basic" alt="The Conversation" width="1" height="1" /><!-- End of code. If you don't see any code above, please get new code from the Advanced tab after you click the republish button. The page counter does not collect any personal data. More info: http://theconversation.com/republishing-guidelines --></p> <p><em><a href="https://theconversation.com/profiles/langis-michaud-647069">Langis Michaud</a>, Professeur Titulaire. École d'optométrie. Expertise en santé oculaire et usage des lentilles cornéennes spécialisées, <a href="https://theconversation.com/institutions/universite-de-montreal-1743">Université de Montréal</a></em></p> <p><em>This article is republished from <a href="http://theconversation.com">The Conversation</a> under a Creative Commons license. Read the <a href="https://theconversation.com/when-laser-surgery-turns-into-a-nightmare-the-toll-can-be-enormous-130518">original article</a>.</em></p>

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How the use of lasers and small satellites helps information get through space

<p>Satellites are becoming increasingly important in our lives, as they help us meet a demand for more data, exchanged at higher speeds. This is why we are exploring new ways of improving satellite communication.</p> <p>Satellite technology is used to navigate, forecast the weather, monitor Earth from space, receive TV signals from space, and connect to remote places through tools such as satellite phones and <a href="https://www.nbnco.com.au/learn/network-technology/sky-muster-explained">NBN’s Sky Muster satellites</a>.</p> <p>All these communications use radio waves. These are electromagnetic waves that propagate through space and, to a certain degree, through obstacles such as walls.</p> <p>Each communication system uses a frequency band allocated for it, and each band makes up part of the <a href="https://imagine.gsfc.nasa.gov/science/toolbox/emspectrum1.html">electromagnetic spectrum</a> – which is the name given to the range of all types of electromagnetic radiation.</p> <p>But the electromagnetic spectrum we are able to use with current technology is a finite resource, and is now completely occupied. This means old services have to make room for new ones, or higher frequency bands have to be used.</p> <p>While this poses technological challenges, one promising way forward is optical communication.</p> <p><strong>Communication with lasers</strong></p> <p>Instead of using radio waves to carry the information, we can use light from lasers as the carrier. While technically still part of the electromagnetic spectrum, optical frequencies are significantly higher, which means we can use them to transfer data at higher speeds.</p> <p>However, one disadvantage is that a laser cannot propagate through walls, and can even be blocked by clouds. While this is problematic on Earth, and for communication between satellites and Earth, it’s no problem for communication between satellites.</p> <p>On Earth, optical communication via fibre optic cables connects continents and provides enormous data exchanges. This is the technology that allows <a href="https://www.vox.com/2015/4/30/11562024/too-embarrassed-to-ask-what-is-the-cloud-and-how-does-it-work">the cloud</a> to exist, and online services to be provided.</p> <p>Optical communication between satellites doesn’t use fibre optic cables, but involves light propagating through space. This is called “free space optical communication”, and can be used to not only deliver data from satellites to the ground, but also to connect satellites in space.</p> <p>In other words, free space optical communication will provide the same massive connectivity in space we already have on Earth.</p> <p>Some systems such as the <a href="https://artes.esa.int/edrs-global">European Data Relay System</a> are already operational, and others like SpaceX’s <a href="https://www.space.com/see-spacex-starlink-satellites-in-night-sky.html">Starlink</a> continue to be developed.</p> <p>But there are still many challenges to overcome, and we’re limited by current technology. My colleagues and I are working on making optical, as well as radio-frequency, data links even faster and more secure.</p> <p><strong>CubeSats</strong></p> <p>So far, a lot of effort has gone into the research and development of radio-frequency technology. This is how we know data rates are at their highest physical limit and can’t be further increased.</p> <p>While a single radio-frequency link can provide data rates of 10Gbps with large antennas, an optical link can achieve rates 10 to 100 times higher, using antennas that are 10 to 100 times smaller.</p> <p>These small antennas are in fact optical lenses, and their compact size allows them to be integrated into small satellites called CubeSats.</p> <p>CubeSats are not larger than a shoebox or toaster, but can employ high speed data links to other satellites or the ground.</p> <p>They are currently used for a wide range of tasks including earth observation, communications and scientific experiments in space. And while they’re not able to provide all services from space, they play an important role in current and future satellite systems.</p> <p>Another advantage of optical communication is increased security. The light from a laser forms a narrow beam, which has to be pointed from a sender to a receiver. Since this beam is very narrow, the communication doesn’t interfere with other receivers and it’s very hard, if not impossible, to eavesdrop on the communication. This makes optical systems more secure than radio electromagnetic systems.</p> <p>Optical communication can also be used for <a href="https://qt.eu/understand/underlying-principles/quantum-key-distribution-qkd/">Quantum Key Distribution</a>. This technology allows the absolute secure exchange of encryption keys for safe communications.</p> <p><strong>What can we expect from this?</strong></p> <p>While it’s exciting to develop systems for space, and to launch satellites, the real benefit of satellite systems is felt on Earth.</p> <p>High speed communication provided by optical data links will improve connectivity for all of us. Notably, remote areas which currently have relatively slow connections will experience better access to remote health and remote learning.</p> <p>Better data links will also let us deliver images and videos from space with less delay and higher resolution. This will improve the way we manage our resources, including <a href="https://www.ga.gov.au/scientific-topics/community-safety/flood/wofs">water</a>, agriculture and forestry.</p> <p>They will also <a href="https://www.ga.gov.au/scientific-topics/earth-obs/case-studies/mapping-bushfires">provide vital real-time information in disaster scenarios such as bushfires</a>. The potential applications of optical communication technology are vast.</p> <p><strong>Banding knowledge together</strong></p> <p>Working in optical satellite communication is challenging, as it combines many different fields and research areas including telecommunication, photonics and manufacturing.</p> <p>Currently, our technology is far from achieving what is theoretically possible, and there’s great room for improvement. This is why there’s a strong focus on collaboration.</p> <p>In Australia, there are two major programs facilitating this - the Australian Space Agency run by the federal government, and the <a href="https://smartsatcrc.com/">SmartSat Cooperative Research Centre</a> (CRC), also supported by the federal government.</p> <p>Through the SmartSat CRC program, my colleagues and I will spend the next seven years tackling a range of applied research problems in this area.<!-- Below is The Conversation's page counter tag. Please DO NOT REMOVE. --><img style="border: none !important; box-shadow: none !important; margin: 0 !important; max-height: 1px !important; max-width: 1px !important; min-height: 1px !important; min-width: 1px !important; opacity: 0 !important; outline: none !important; padding: 0 !important; text-shadow: none !important;" src="https://counter.theconversation.com/content/126344/count.gif?distributor=republish-lightbox-basic" alt="The Conversation" width="1" height="1" /><!-- End of code. If you don't see any code above, please get new code from the Advanced tab after you click the republish button. The page counter does not collect any personal data. More info: http://theconversation.com/republishing-guidelines --></p> <p><em><a href="https://theconversation.com/profiles/gottfried-lechner-877898">Gottfried Lechner</a>, Associate Professor and Director of the Institute for Telecommunications Research, University of South Australia, <a href="http://theconversation.com/institutions/university-of-south-australia-1180">University of South Australia</a></em></p> <p><em>This article is republished from <a href="http://theconversation.com">The Conversation</a> under a Creative Commons license. Read the <a href="https://theconversation.com/were-using-lasers-and-toaster-sized-satellites-to-beam-information-faster-through-space-126344">original article</a>.</em></p>

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Laser hair removal: Here’s everything you need to know

<p><a href="https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/hirsutism-excessive-hair-women">Unwanted facial and body hair</a> can affect the way we feel, our social interactions, what we wear and what we do.</p> <p>Options to camouflage or remove unwanted hair include plucking, shaving, bleaching, using creams and epilation (using a device that pulls out multiple hairs at once).</p> <p>Longer-term options include electrolysis, which uses an electrical current to destroy individual hair follicles, and laser therapy.</p> <p>So what is <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/j.1468-3083.2005.01327.x">laser therapy</a>? What can it achieve? And what are the side-effects?</p> <p><strong>How does laser treatment work?</strong></p> <p><a href="https://www.sciencenewsforstudents.org/article/explainer-what-laser">Lasers</a> emit a wavelength of light with a specific single colour. When targeted to the skin, the energy from the light is transferred to the <a href="https://www.medicinenet.com/script/main/art.asp?articlekey=4340">skin and hair pigment melanin</a>. This heats up and damages the surrounding tissue.</p> <p>But to remove hair permanently and to minimise damage to the surrounding tissue, the laser needs to be targeted to specific cells. These are the hair follicle stem cells, which sit in part of the hair known as the hair bulge.</p> <p>As the skin surface also contains melanin, which we want to avoid damaging, people are carefully shaved before treatment.</p> <p><strong>Will it remove hair permanently?</strong></p> <p>Laser treatment can either permanently reduce the density of the hair or permanently remove unwanted hair.</p> <p>Permanent reduction in hair density means some hairs will regrow after a single course of therapy and patients will need ongoing laser treatment.</p> <p>Permanent hair removal means none of the hairs in the treated area will regrow after a single course of therapy and no ongoing laser therapy is needed.</p> <p>Whether hair is removed permanently or just reduced in density is influenced by:</p> <ul> <li>The colour and thickness of the hairs being treated</li> <li>The colour of the patient’s skin</li> <li>The type and quality of the laser used, and</li> <li>The competence and training of the person operating the laser.</li> </ul> <p>However, if you have grey hairs, which have no melanin pigmentation, currently available lasers don’t work.</p> <p><strong>How many treatments will I need?</strong></p> <p>The number of treatments you’ll need depends on your <a href="https://www.arpansa.gov.au/sites/default/files/legacy/pubs/RadiationProtection/FitzpatrickSkinType.pdf">Fitzpatrick skin type</a>. This classifies your skin by colour, its sun sensitivity and its likelihood to tan.</p> <p>Pale or white skin, burns easily, rarely tans (Fitzpatrick types 1 and 2) People with dark hair can usually achieve permanent hair removal with 4-6 treatments every 4-6 weeks. People with fair hair will generally only achieve permanent hair reduction and after an initial course of treatment may need 6-12 treatments a month apart.</p> <p>Light brown skin, sometimes burns, slowly tans to light brown (type 3) People with dark hair can usually achieve permanent hair removal with 6-10 treatments every 4-6 weeks. People with fair hair will generally only achieve permanent hair reduction and after an initial course of treatment may require 3-6 repeat treatments a month apart.</p> <p>Moderate brown to dark brown skin, rarely burns, tans well or to moderate brown (type 4 and 5) People with dark hair can usually achieve permanent hair reduction with 6-10 treatments every 4-6 weeks. Maintenance will usually be required with 3-6 monthly repeat treatments. People with fair hair are unlikely to respond.</p> <p>Re-treatments must be long enough apart to allow new hair growth to reach the level of the bulge.</p> <p><strong>What side effects or complications should I be aware of?</strong></p> <p>You will be advised to wear goggles during the treatment to prevent eye injury.</p> <p>You will also experience some pain during treatment, especially the first few. This is mainly due to not removing all hair in the area to be treated before the procedure. Hairs missed while shaving absorb laser energy and heat the skin surface. There is less pain with repeat treatments at regular intervals.</p> <p>Your skin will feel hot for 15-30 minutes after laser treatment. There may be redness and swelling for up to 24 hours.</p> <p>More serious side effects include blisters, too much or too little skin pigmentation, or permanent scarring.</p> <p>These generally occur in people with a recent suntan and the laser settings have not been adjusted. Alternatively, these side-effects can occur when patients are taking <a href="http://www.webstercare.com.au/files/Continuing_Education_March_2015.pdf">medications</a>that affect their skin’s response to sunlight.</p> <p><strong>Does the type of laser matter?</strong></p> <p>The type of laser not only influences how well it works, it influences your chance of side-effects.</p> <p>Lasers suitable for hair removal include: <a href="https://www.ncbi.nlm.nih.gov/pubmed/10759801">long-pulse ruby lasers</a>, <a href="https://www.sciencedirect.com/science/article/pii/S1090820X05000828">long-pulse alexandrite lasers</a>, <a href="https://www.ncbi.nlm.nih.gov/pubmed/12766964">long pulse diode lasers</a> and <a href="https://jamanetwork.com/journals/jamadermatology/fullarticle/478428">long-pulse Nd:YAG lasers</a>.</p> <p>Intense pulsed light (IPL) devices are not laser devices but flash lamps that emits multiple wavebands of light simultaneously. They work in a similar way to lasers, albeit less effectively and they are much less likely to permanently remove hair.</p> <p>To minimise the risk of damage to melanin producing cells on the skin surface, the choice of laser and how it’s used can be matched to your skin type.</p> <p>Fair skinned people with dark hair can use an IPL device, an alexandrite laser or a diode laser; people with dark skin and dark hair can use a Nd:YAG or diode laser; and people with blond or red hair can use a diode laser.</p> <p>To control the spread of heat and unwanted tissue damage, short laser pulses are used. The energy of the laser is also adjusted: it needs to be high enough to damage the bulge cells but not so high to cause discomfort or burns.</p> <p><strong>Can I buy a home laser device and do it myself?</strong></p> <p>Home laser devices and IPL home devices are available in Australia and cost between $200 and $1,000. But they don’t tend to work as well and you need to use them repeatedly to maintain hair reduction.</p> <p>Parameters are only set for people with fair skin (Fitzpatrick types 1 and 2) and dark hair. For safety, energy settings are capped. And in inexperienced hands, <a href="https://www.ncbi.nlm.nih.gov/pubmed/20625788">complications</a> may still arise. This includes burns, pain, blistering and changes to skin pigmentation.</p> <p>By contrast, medical grade lasers must be registered with the government regulator, the <a href="https://www.tga.gov.au/can-i-import-ithttps:/www.tga.gov.au/can-i-import-it">Therapeutic Goods Administration</a>. There are also national and state-based regulations about the <a href="https://www.arpansa.gov.au/understanding-radiation/radiation-sources/more-radiation-sources/lasers">facility</a> where the laser is used, <a href="https://www.lasersafetyonline.com.au/">compulsory laser safety training requirements</a> and state-based qualifications and licensing for laser operators.</p> <p>So, a safe and regulated laser in the hands of a skilled professional is recommended.</p> <p><strong>When to see your GP</strong></p> <p>Not all excess hair is cause for concern. But severe <a href="https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/hirsutism-excessive-hair-women">hirsuitism</a> (excess growth of dark and coarse hair over areas of the body where it ordinarily wouldn’t grow) or <a href="https://www.dermnetnz.org/topics/hypertrichosis/">hypertrichosis</a>(excess hair growth for someone’s age, sex or race) can be clues to underlying illness.</p> <p>Hirsutism, especially when associated with symptoms including irregular periods or acne, can be caused by <a href="https://www.tandfonline.com/doi/full/10.1586/edm.11.45?scroll=top&amp;needAccess=true">extra androgen hormones</a>. Hypertrichosis later in life can be a sign of malignancy.</p> <p>Your GP can investigate these.</p> <p><em>Written by Rodney Sinclair. Republished with permission of </em><a href="https://theconversation.com/thinking-of-laser-hair-removal-heres-what-you-need-to-know-113561"><em>The Conversation</em></a><em>.</em></p>

Beauty & Style

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6 surprising risks with laser eye surgery

<p>For most, corrective laser eye surgery brings great results, correcting nearsightedness, farsightedness, astigmatism and more. But for some rarer cases, eye surgery can have painful and sometimes disastrous consequences. Here are some of the laser eye risks you should be aware of when considering undergoing the corrective surgery.</p> <p><strong>Infection –</strong> One of the worst outcomes post laser-surgery, infection can occur in one in every 5000 cases. In the rarest cases, patients can develop a corneal ulcer as a result. To avoid infection, it is recommended that patients avoid swimming and hot tubs in the first few weeks post-surgery.</p> <p><strong>Glare/haziness –</strong> For some shortsighted patients, they will experience more glare than they had before the surgery, though this generally goes away after a few months. For some, however it is occasionally permanent.</p> <p>For most patients post-surgery, they will experience hazy vision which is caused by the healing of their eye and which usually dissipates in the weeks to come. In some cases, further surgery may be necessary to fix hazy vision complications.</p> <p><strong>Under/over-correction –</strong> Because everyone’s eyes are unique, some patients can leave surgery with their vision over- or under-corrected. Significant under-correction can call for a re-surgery, while over-correction can be treated with eye drops, further surgery, and temporary contact lenses.</p> <p><strong>Regression –</strong> Some patients experience regression, or the return to some extent of their pre-surgery shortsightedness, but a slight regression is normal as the eye heals.</p> <p><strong>Dry eyes –</strong> Post-surgery, many patients experience the discomfort of dry eyes, though it generally improves as time passes. For some, the damage may be permanent, and the prolonged use of artificial tears may be necessary. For those who already suffer from dry eyes, laser surgery is not recommended.</p>

Eye Care