Q SWITCHED ND YAG LASER
WHAT IS Q-SWITCHED?In addition to their categorization by wavelength, lasers can be divided into continuous wave (CW) or pulsed. A CW laser delivers a steady stream of light that is measured as average power in watts or kilowatts. A pulsed laser delivers a very short but intense light emission followed by a period of no light. If the laser is repetitively pulsed, the pulse repeats itself on a regular basis. The time between the pulses is referred to as the interpulse period and the length of each pulse is called the pulse duration. The number of hertz (Hz) represents the number of pulses emitted per second. The length of the pulse duration is an important characteristic of any pulsed laser/light device. Pulses lasting a few milliseconds (10 -3 ) are generally characterized as long pulses. Nanosecond (10 -9 ) pulses are considered short. Q-switched NdYAG laser pulses are typically 3-7 nanoseconds in length.
CLINICAL APPLICATIONS OF Q-SWITCHED ND YAG LASERIn Q-switched mode, Nd:YAG produces 2 wavelengths, one in the infrared range (1064 nm) and a second beam of 532 nm wavelength which is useful for superficial skin lesions. Q-switching refers to the technique of making the laser produce a high intensity beam in very short pulses.While the epidermal lesions respond best to 532 nm (frequency doubled NdYAG) the dermal lesions are better treated with 1064 nm. Q-switched lasers are the gold standard for treatment of tattoos. Q-switched NdYAG laser 532 nm and 1064 nm frequency doubled had been studied for treatment of melasma with poor results. Normal skin color was rarely achieved.Dark lips are a common cosmetic concern in India. Two to four sessions of Q-switched 532 nm is an effective treatment for lip lightening.Q-switched NdYAG laser 1064 nm offers a new technology that helps treat scars and wrinkles at their root, deep in the skin. Using laser energy that penetrates deeply without injuring the top layer of skin, the deep dermis is stimulated to produce natural collagen and other vital proteins that make up healthy, youthful skin.