Introduction
Laser is one of the latest technological innovations, which uses simulated light emissions for the illumination of tissues. Lasers find wide application in medicine and telecommunications, primarily in passing information. Lasers are important in providing placate to human life and survival. However, like any other technology lasers have disadvantages and advantages in their applications. Lasers involve emitting light, which is usually coherent, monochromatic, and long-ranged. A laser is a type of light radiation within an electromagnetic spectrum, which can induce effects as it flows or passes through matter. Different types of lasers emit different monochromatic waves, which form a broad light spectrum with varying wavelengths. Different types of lasers include ultraviolet laser, X-ray laser, hydrogen laser, and infrared laser. Much of today’s technological advancements and innovations have used the principle of laser technology to provide solutions to human problems, the latest invention being the innovation CD’s and DVD’s technology. TVs, telephones, and fiber optic communication -underpin the internet use principles of laser technology (Karman, McDonald, New, Woerdman, 1999, pp.10-14).
Laser light is not visible, though our technological innovations have created the use of lasers in different applications like manufacturing, medicine, and welding to create efficiency. However, lasers have biological effects if accidentally or intentionally monochromatic laser beam collides with cells of a living organism. Researchers have carried out experiments to establish the extent to which lasers are able to affect human tissues with little discovery. Strong effects of laser collision can cause laser-induced shocks and dire bubble formations in an individual, which can cause death. Lasers have an effect on the eye that is, if monochromatic laser light encounters the cornea, blindness can occur. Shock waves have an effect, especially that which involves forming radicals within white and red blood cells. Biologically, if the light of high intensity and wavelength collides with lymphocytes, there is massive damage to cells. The extent and effectual smash-up are in relation to pressure and the number of pulses emitted at an instant (Karman et al, 1999, pp. 135-138).
Physics Background
Laser technology backdates to the 1950s when Townes invented the maser. His main aim was to find a gadget that primarily used light for the illumination of tissues and matter. These two technologies (lasers and masers) almost use the same physics ideology, which is the activation of atoms, hence providing them with more energy than they had. On the other hand, after these atoms lose energy, they return to their original energy state, whereby the energy released is in form of high frequencies. The main difference between masers and lasers is that lasers use light for illumination, whereas masers use radio energy during operation (Gilmore, 1962, pp.89-92)
The laser as a physics application became operational when scientist Maiman invented the ruby laser through the use of light. Maiman made the ruby light using particles of aluminum oxide that contains minute amounts of chromium. Chromium being a colored mineral, gives the ruby light desired colors. For ruby light to release packets of energy, light must excite its atoms, which results in a concentration of energy, hence the release. The release of energy by atoms is never uniform because some atoms discharge energies contrary to desired phases (Gilmore, 1962, 200-201)
Research discoveries have proved that laser users can produce lasers from different substances belonging to the three states of matter namely: solids, liquids, and gases. Some physicists have even advanced the technology and currently, they are using Jelo in production, complex integration of many matter properties. The main factor behind the production of laser for different substances is that matter in any state has stored energy in a form that is stable, although not balanced. Stimulation of emissions results when excited energy amounts surpass energy levels with low energy amounts. In this regard, all-laser materials must receive some exiting energy for emissions to occur in their equilibrium states. In addition, users may continue to use laser material so long as energy levels do not go beyond minimum levels, and the laser materials maintain their decay rates (Narducci & Neal, 1988, pp.159-160).
Mechanisms of Interaction with Biological Tissues
The laser effect involves radiations emitted from different types of lasers, for example, visible light and ultraviolet upon tissues. On interaction with tissues, a reaction, which is photochemical in nature, occurs. However, it is not easy for one to discover its effects immediately. Lasers arriving from ultraviolet radiations are able to cause temperatures of tissue bodies’ to change, thus causing thermal effects. For example, an unprotected eye or direct looking at a laser beam can damage the eye retina, cornea, or lens. If a laser source transmits infrared light into the eye, the lens converges to a narrow spot on the retina, thus concentrating more light on one side; which is harmful. If the central area happens to be the macula or fovea, then blindness may occur. The monochromatic light disjoints the tissues far apart, which may result in blindness because; the cornea tissues are not repairable easily. Excessive light leads to permanent eye damage, in case individuals do not take medical precautions. What happens during collision is that, cornea cells are able to absorb ultraviolet emissions, which are protein in nature. After collision and absorption, the cells deactivate or denature monochromatic ultraviolet radiation causing redness of the eye causing photophobia and tearing (U.S. San Diego, 2009, para.4-6). Infrared radiation, on the other hand, can cause haze to the eye by thermally damaging the cornea, due to heat on eye tissues and the cornea. In addition, translucence can occur if the eye gets exposed to infrared radiations for a long time, causing surface problems.
Lasers also have consequential skin effects. They cause thermal skin damage linked to operations of higher wavelength from lasers beams. Thermal skin damage depends on a number of factors like skin’s vascular flow, the surface area of the area affected, scattering, and coefficient at which laser is traveling and colliding with tissues and skin cells. Some lasers traveling at sub-microsecond speed stimulate acoustic waves, which in turn cause thermal heat to build up in skin cells, hence destroying cell ligaments. Continual exposure to these types of lasers causes pulses within skin cells and tissues, thus resulting in diseases like cancer. Medics use laser photocoagulation to stop infrared radiations from causing hemorrhage in patients. Biological tissues are indeed prone to major attacks especially from lasers thus disturbing the physical heterogeneity of tissues. These tissues interact with laser beams causing scattering. Scattering depends on critical connotations like the area affected and the intensity of the laser. If absorption is great, then there is diverse scattering resulting from thermal build-up.
Interaction of laser with molecular tissues a free radical complex result, which has different effects on tissues. This radical has free-moving electrons, which affect the physiological process hence, pathological change occurs in tissues. On the other hand, the molecular chemical structure of tissue fluids and proteins in the body may be destroyed (Huang, Zhao, Zhong, Guo and Sun, 1997, pp.315-325). Laser radiations also cause biologically stimulating effects on blood cells, enzymes, and metabolic energies of tissues. Proteins are able to cross-link with laser radiations causing complications in the body of living organisms. Clinical studies have shown that, apart from the normal negative laser effects, lasers can also be instrumental in healing processes. It is important to note that, different types of lasers induce different effects, which can be positive or negative. Lasers of high intensity can cause scattering and damage to body cells and tissues, whereas low-intensity laser irradiations are applicable in medicine for treatment purposes. Light from a laser source can penetrate into tissues to enhance cell-reproduction and generation. This happens due to the fact that a laser beam can provide energy, which is essential in repairing and regenerating tissue growth and strengthening the muscles.
Applications of laser in medicine and biology
Some types of lasers are useful in healing wounds by stimulating some common cells like fibroblasts, which are essential in the healing of wounds. Fibroblasts produce collagen, which the body uses in synthesizing protein. If there is the formulation of proteins, tissues can get replacement energies essential for repairing or replacing worn-out cells. Laser light of low irradiation intensity can be of greater importance as the energies replicated from it cause additional fibrous tissue creation, thus reducing skin effects like burning up, scratches, and predominant cuts. Researchers have conducted experiments to prove whether lasers produce vasodilatation with a lot of success. It is true that laser radiations have anti-endemic consequences and find wide application in activating the flow of fluids in the lymphatic system. This reduces itchy inflammatory bruises that are persistent due to prolonged bruising. On the other hand, medics can use lasers to increase enzymatic flow in terms, of output work. Enzymes- catalytic in nature are beneficial in the digestive system where they help red blood cells in carrying out body functions. The body forms new capillaries through laser irradiation and emissions. Body processes like angiogenesis receive power by a conceptual increase in the size of blood vessels resulting from laser effects (Wolbarsht, 1991, pp.31-37).
Research has indicated that medics can use laser light to recover numb nerves and physical impairments like impaired limbs. If a laser beam of moderate intensity interacts with these affected areas, the cells will rejuvenate resulting in healing and reconnection of muscles. The introduction of low laser radiations with low monochromatic frequency can help to formation of free radicals, which the body uses for activating fluids like immunoglobulins and red blood cells. Consequently, the body creates enzymes, which in turn provide the convulsive environment for digestion.
Lasers find application in a variety of medicine ranging from malignant tumors to cardiovascular treatments. For example, from research discoveries, laser-induced fluoresce is important in performing experiments that will decide or identify certain diseases. Physiologists use photochemical reactions to determine biological therapy, which heals tissues and enhances molecular count. Photodynamic therapy popularly known as PDT- laser application, used in healing skin effects created by strong laser radiations, is an application of laser technology. Optical properties are now applicable in medicine, where laser-induced fluorescence treatments illuminate ill tissues. Medics use Ruby lasers in a number of medical applications like removing skin scars, wrinkles, and some dominant stretch marks. In eye surgery, doctors use lasers to treat eye cornea problems. On the other hand, medics use laser scalpel technology in general medicine – gynecology, laparoscopic, and surgery. In dentistry, doctors do endodontic surgery effectively using laser light, whereby it allows oral maxillofacial surgery and tooth removal or whitening. Therapeutically, laser techniques like photobiomodulation apply lasers in therapy processes to heal patients.
Conclusion and Summary
High-intensity laser beams are destructive when they encounter issues and molecules or living organisms. They cause side effects, related to thermal and photochemical effects, which cause diseases and other side effects. Medics use low-intensity laser light in therapy for curing inflammatory diseases, synthesizing proteins, reducing pains, and revascularize wounds. Strong sunlight, which emits ultraviolet radiation, causes cell damage. Laser radiations of low intensity, however, can lead to biomodulation and healing of chronic wounds. Medics can also apply laser radiations in adjunctive therapy, where low thermal heat lasers increase the level of hemoglobin and red blood count. However, laser treatment depends on the intensity of laser light and the method of treatment used by medics. Wrong application and use of lasers may cause an adverse effect on the overall functioning of the body systems. Patients should use appropriate and correct treatment dosage to avoid further invading of body tissues. Outside the field of medicine, scientists use lasers in the manufacturing industry like cutting metals and welding. They are also applicable in the photochemical industry, military, and communication technology.
Reference List
Gilmore, C. P. (1962). The Incredible Ruby Ray. Popular Science, 181: 89-92, 200.
Huang, Y. M., Zhao. H., Yux, Zhong, W., Guo, J. L., Sun, S. Q. and Li Y. (1997).
Damaging mechanism of free radical to the membrane molecules of red blood cell. Acta Biophys Sin, 13, 315−323
Karman, G.P., McDonald, G.S., New and Woerdman. (1999).
Laser Optics: Fractal modes in unstable resonators”, Nature, 402, p.138.
Narducci, M. L. and Neal, A. B. (1988). Laser physics and laser instabilities. New Jersey: World Scientific Pub Co Inc.
U.S. San Diego. (2009). Laser safety program: biological effects of laser radiation. Blink. Web.
Wolbarsh, M. L. (1991). Laser application in medicine and biology. Georgia: Springus.