Tag: Radiation

The History of Laser Hair Removal

The lasers used for laser hair removal developed from a theory instituted by the Nobel prize-winning physicists Albert Einstein and Max Planck. This theory, first introduced in the 1920s, defined stimulated emission, or laser. The word laser is an acronym for light amplification by stimulated emission of radiation. However, it wasn’t until the 1960s that the first true laser was built and patented by Gordon Gould, an American physicist.

Laser hair removal devices of the 1960s sent out a continuous wavelength which caused damage to the surrounding skin tissue. In the late 1960s, Dr. Leon Goldman was the first to begin testing a ruby laser for hair removal. It was also in this time frame that the Q switch with developed for use with a laser. With the development of the Q switch it was possible to control the energy of the laser beam to be sent to out in controlled pulses. The Q switch worked much in the same way as a camera shutter.

Early devices for laser hair removal proved to be ineffective. In order to remove the hair follicle, there was severe damage to the surrounding skin area. The ruby laser, as well as the argon laser, are no longer used for laser hair removal.

Throughout the next several decades, researchers and physicists continued to experiment and test lasers for successful hair removal. It wasn’t until the 1980s that the first laser was introduced as a safe and effective method of hair removal. This discovery actually happened by chance when scientists noted that birthmarks treated with certain types of lasers caused the hair in that area to disappear and not grow back.

The FDA cleared the first laser for hair removal in 1995 . This laser, called the Soft Light, was a NeoDymium Yttrium Aluminum Garnets laser and was manufactured by Thermolaise. This laser was used with a chromophore of carbon-based lotion. After the skin was waxed, the carbon-based lotion would be rubbed onto the skin and enter the hair follicle. The beam of light produced by the laser would heat the carbon quickly and destroy the hair follicle. However, this type of laser treatment could easily damage nearby skin cells. Eventually, this type of laser hair removal proved to be less effective than targeting the natural pigmentation that existed in the skin.

In 1997, several types of laser hair removal devices were cleared by the F DA. One of these was the ruby laser, which used a shorter wavelength system. However, clinical research eventually showed that the laser did not produce damage far enough down the hair shaft to result in permanent hair loss. Researchers also found that if a t the ruby laser was used on people with dark or tan skin there was a high risk of hyperpigmentation. Other types of laser hair removal devices today include alexandrite, diode, and NeoDymium Yttrium Aluminum Garnets lasers.

Research and development in the area of laser hair removal are still in the early stages. However, continuing research, testing and development in this area continues to produce safer and more effective equipment.

Orthopedic Problems in Adolescents

Physical health problems encountered during adolescence can affect the development of the body, if not treated. There are few anatomic regions, such as spine, knee and ankle, in adolescents which can get orthopedic problems such as Osgood-Schlatter disease, and Slipped Capital Femoral Epiphysis.

Osgood-Schlatter disease is caused due to injury or overuse of the knee which causes swelling and pain in the area below the knee, above the shin bone. The patellar tendon and the soft tissues surrounding it gets inflamed, because of the constant pulling of the area where the tendon joins the below knee. Usually, adolescents who participate in sports actively and are athletic, such as football, basketball, soccer, ballet and gymnastics, tend to get the Osgood-Schlatter disease. Boys of age eleven to fifteen and girls of age eight to thirteen are at greater risk. The reason why adolescents get this problem is that their bones grow faster when compared to the tendons and muscles in this age and because of this the muscles and tendons stretch and become tight.

The symptoms of Osgood-Schlatter disease are swelling of knee, tenderness below knee area and limping. The doctor will check the medical history of the patient and will conduct physical examination and diagnostic procedures such as taking an X-ray. The physician will decide on the treatment to be done by studying the overall health, age, medical history, tolerance for certain medications and extent of the disease. Treatment will include medications, rest, compression, elevation, neoprene knee sleeve and physical therapy. The main aim will be to control and limit the knee pain by cutting down on the adolescents physical activities. Usually the Osgood-Schlatter disease gets healed over a period of time and in very rare cases is a surgery required.

Slipped capital femoral epiphysis is a problem which affects the hip joint. The ball or head of the thigh bone, also known as femoral head slips from the thigh bones neck. Because of this the hip joint becomes stiff and painful. Slipped capital femoral epiphysis is the most common disorder of the hip which can happen in both the hips or one and it is more common in boys when compared to girls. Basically, adolescents of the age ten to eighteen years and who are overweight can be affected by this condition. The condition can arise over a time interval of few weeks or years. The condition, if resulted because of trauma and is also called acute slip and if results after a period of time is called chronic slip. Slipped capital femoral epiphysis is caused because of medications, radiation treatment, thyroid problems, and chemotherapy.

There are three degrees of intensity of slipped capital femoral epiphysis, mild, moderate and severe. In mild slipped capital femoral epiphysis, only one third of femoral head slips from the thigh bone. In moderate, one third to half slips and in severe, more than half of the femoral head slips. The symptoms of this condition are pain in hip which increases upon movement, pain in thigh, knee & groin and limpness in the leg. When an adolescent walks there will be a clicking sound in the hip and his/her legs will be turned outwards.

Apart from studying the medical history of the patient, the doctor will recommend diagnostic procedures such as bone scans, X-ray, magnetic resonance imaging and blood test. The bone scans will determine the arthritic changes and degenerative changes in the joints, which helps to detect tumors & bone diseases and the cause of pain and inflammation. The X-ray will give the inside picture of the bones, tissues and organs. The magnetic resonance imaging provide detailed image of the structures within the body with the help of large magnets. It is best if slipped capital femoral epiphysis is determined in the early stages, so that the femur bones head doesnt slip off any further. The adolescent may need to undergo a surgery along with physical therapy.

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How Lasers Work in Laser Hair Removal

Laser hair removal works by the process of selective targeting of a specific area of the body and using a specific wavelength to absorb light into that area. It does not work on a hair by hair basis, instead it focuses a wide beam of light that treats many hairs at one time. The wavelength of light absorbed has to be sufficient enough to damage the targeted tissue area while leaving the surrounding area basically untouched. The principle behind this process is called selective photothermolysis.

Lasers are intense beams of monochromatic and coherent light. These light beams are produced by laser devices that contain either minerals or gases. The four main types of lasers are solid state, semiconductor, gas and dye.

An electric current stimulates the gas or mineral properties which excites the atoms. The atoms then emit narrow, cohesive, parallel light beams which are all the same wavelength. The light beams are focused just for a fraction of a second on the dark hair pigment at the matrix of the dermal papilla, which is the small, cone shaped indentation at the base of the hair follicle that the hair bulb fits into. The light beam is absorbed and heats the pigment which vaporizes the dermal papilla. The more intense the light beam the hotter it makes the pigment. This results in the dermal papilla being severely damaged or destroyed.

Most people believe that laser hair removal works best on hair that is in its anagen phase. This means that the hair is actively growing and is attached to the dermal papilla. The theory behind this belief is that if the dark pigment in the hair shaft extends all the way down to the dermal papilla, it will be destroyed and vaporized by the coherent light beam that is focused upon the area. This happens because the light beam will follow the dark pigment all the way down to the derma papilla.

Visible light has wavelengths that range from 390 to 770 nm, or nanometers. Lasers operating in this range allows for successful laser hair removal without causing any damage to the dermal tissue. Lasers with a light source that operates between 700 to 1000 nm targets melanin in the hair shaft effectively. For example, the wavelength of an alexandrite laser is 755 nm, which is red in the visible range of the electromagnetic spectrum, making its target melanin. The stronger, or greater, the wavelength, the deeper it penetrates target selectively absorbing the wavelength.

Laser hair removal uses several varying wavelengths of laser energy. These wavelengths range from near infrared radiation to visible light. The three most commonly used lasers for hair removal are Alexandrite, Pulsed diode array, and NeoDymium Yttrium Aluminum Garnets, Also know as Nd:YAGs. The wavelengths of these lasers are 755nm, 810nm, and 1064nm respectively.

Laser hair removal utilizes a complex system of science and physics which are precisely balanced to work effectively and safely on the human body. As technology continues to advance in laser hair removal, this process continues to grow in popularity.