Permanent hair reduction and removal is an easy task for light and radiation based methods which kill the hair from growing when it absorbs intense light or radiation. The difference in hair and skin like the laser treatment is often used to the advantage of these processes so that the skin absorbs less light and the hair absorbs most light, and in some instances, artificial dark spots can be introduced to increase absorption. Most of the methods that involve radiation are yet experimental.
The advancement of hair removal technologies based on lasers, optics make use of different areas of the electromagnetic spectrum including visible light, infrared, ultraviolet light and other forms of more intense radiation like microwave and once X-ray. These devices have to be carefully calibrated to give appropriate dosage to kill only the unwanted hair cells and not to have irrecoverable side effects on the skin. Although cooling equipment can make up for the heat absorbed by the skin, it does not make up for the radiation dosage.
Intense Pulsed Light (IPL) Based Hair Removal
Intense pulsed light normally uses the same concept as the laser treatment to target the hair. The pulses and the wavelengths are customized according to the hair and skin condition; 500 nm to 1200 nm. The feature that makes the laser treatment distinct is the use of monochromatic light. This method has the advantage of safety due to its non coherence and maintains a near efficiency to the laser treatment.
Biotechnology, Dermatology and Medical Device manufacturers often fund researches for IPL and laser technologies.
The process emits most wavelengths of the visible light as well as some bands of infrared radiation allowing the expert to better plan and have more flexibility and options in treatment of skin with special conditions. This process might take up to 10 sessions to obtain a semi permanent hair removal.
Complicated skin conditions and health problems directly impact the safety and the recovery time of the patient in laser and IPL treatments. Recent use of other methods such as waxing, plucking sugaring, use of creams & sprays often interferes with the pre-treatment skin condition and the patients are recommended to wait before continuing to proceed to the IPL or laser treatment.
The side effects by the intense light include discolouration of the skin, burns etc. Black garments are also likely to interfere with the process and are a fire hazard might the beam come in direct contact with them.
Photodynamic Therapy for Hair Removal
The process is typically intended for killing unwanted cells like cancer or permanent removal of hair. Being an experimental technology, the process is being tested and experimented upon to get more know-how and fix the side effects and related issues. When combined with the use of hair removal drugs, the process has proved to be a promising hair removing technique. Photodynamic therapy or anti-inflammatory therapy are also used in combination with this process to facilitate a refined removal of hair. Spot size is a primary parameter to be considered in processes involving light such as this.
Use of X-ray for Hair Removal
The observation that radiation such as the X-rays were a cause of hair loss resulted in development controlled procedures that use the same to deliberately remove body hair. This was picked up by many clinics who acquired significant expertise in the process. Though an effective and painless method, the side effects were scarring, radiation dosage resulting in cancer and other radiation sickness effects, the process was banned by most governments.
This has also given the precedence for not allowing further technologies into the commercial industry without first fully understanding the side effects and researching the counter measures if any.
Being a hot research and development topic, with many procedures yet experimental, the topic area is well covered in published literature. Even though most researchers are funded by manufacturers, the research often produces fair warnings and detailed analysis of limitations of the processes while they are still experimental.
Research work shows the necessity of preheating of the treatment volume, pre-cooling, in-treatment cooling and post-treatment cooling of the epidermis higher than the treatment volume.
Most of the research work is being done to improve beam focusing techniques for scattering reduction and to avoid skin damage, techniques for reducing the net cost and increasing the efficacy and efficiency of optical radiation so that it can be better used in hair removal treatment as well as other dermatological treatments.
With the benefits of information age on hand, the research is also being done on simulation level with software available to evaluate the effects of hair removal from light and radiation based systems. This optimizes the process for the final use on patients.