What is an alexandrite laser?

What is a laser?

A laser (light amplification by stimulated emission of radiation) works by emitting a wavelength of high-energy light, which when focused on a certain skin condition will create heat and destroy diseased cells. Wavelength is measured in nanometres (nm).

Various kinds of lasers are available for use in skin surgery. They are differentiated by the medium that produces the laser beam. Each of the different types of lasers has a specific range of utility, depending on its wavelength and penetration. The medium amplifies the light of a particular wavelength as it passes through it. This results in the release of a photon of light as it returns to a stable state.

The duration of the light pulses affects the laser’s clinical applications in skin surgery.

What is an alexandrite laser?

An alexandrite laser is one that uses an alexandrite crystal is used as the laser source or medium. The alexandrite laser produces a specific wavelength of light in the infrared spectrum (755 nm). It is considered a red light laser.

Alexandrite lasers are also available in the Q-switched mode. Q-switching refers to the technique of making the laser produce a high-intensity beam in very short pulses.

How does an alexandrite laser work?

The wavelength of high energy light emitted by the laser is converted to heat energy and this damages the specific target area. Thus alexandrite lasers work by a process of photothermolysis: this means using light to heat a selected area for destruction (lysis).

Alexandrite lasers cause very precise tissue destruction of the lesion and leave the tissue in the surrounding area undamaged.

What is an alexandrite laser used for?

FDA has approved a range of alexandrite laser machines emitting infrared light (wavelength 755 nm) for various skin disorders. The following skin disorders can be treated with Alexandrite laser beams.

Hair removal

Light pulses target the hair follicle causing the hair to fall out and minimising further growth.

May be used for hair removal in any location including underarms, bikini line, face, neck, back, chest and legs.

Generally ineffective for light coloured hair, but useful for treating dark hair in patients of Fitzpatrick types I to III, and perhaps light-coloured type IV skin.

The typical settings employed include pulse durations of 2 to 20 milliseconds and fluences of 10 to 40 J/cm2.

Extreme caution is recommended in tanned or darker skinned patients, as the laser can also destroy melanin, resulting in white patches of skin.