Treatment of pigmented lesions.

The method of treatment of pigmented skin changes, developed and patented by the LINLINE company and implemented in the Multiline™ device in the mode of using the Ruby and Alexandrite lasers.

Advantages of the LINLINE™ method.

  • Excellent results in the treatment of epidermal and dermal pigmented skin changes..
  • Short rehabilitation term after the procedure.
  • There is no risk of hypopigmentation.

  Treatment results Before-After


About the mechanisms of treatment of pigmented skin changes.

The method of treating the pigmented lesions implemented in the Multiline™ device fundamentally differs from other classical laser methods. Usually for these purposes either long-pulse methods (with pulse duration from hundreds of microseconds to tens of milliseconds) or methods of mechanical destruction of the spots using nanosecond Q-sw pulses are used. Both these methods are far from perfect.

During the treating of pigmented spots using long pulses, overheating of not only the pigmented spot, but also of the surrounding tissues is inevitable. Thermal relaxation time of the melanin grain is about one millisecond, so during operating of the laser pulse, melanin not only warms up, but also effectively radiates heat to the surrounding tissues.
In case of treating the epidermal hyperpigmentation this heating may lead to superficial burns and appearance of a shallow necrotic area. With the rejection of the received peel there is also rejection of the pigmented lesions. With increasing the pulse energy, an increase in the zone of necrosis can lead to increase of hyperpigmentation and even scarring.
In case of dermal hyperpigmentation treatment the chance of a good aesthetic resul is generally reduced to zero. Because of excessive heat outflow in the deep layers of skin the increase of hyperpigmentation becomes inevitable. Similarly, risk of scarring noticeably increases.

The method of using Q-sw lasers for hyperpigmentation treatment has been known since the 1970’s. This method is based on the formation of powerful acoustic waves in the grains of melanin that have absorbed short nanosecond pulses. Those waves mechanically destroy skin cells inside which there are melanin grains. If the track length of acoustic waves was limited by the size of cell, this method might be considered almost ideal. However, there is no control on the track length of an acoustic wave. As a result, the traumatised area appears to be certainly larger than the hyperpigmentation area. The consequences of such treating are hypopigmentated or hyperpigmentated areas, long healing periods, and in case of treating of dermal pigmentation disorders often causing scarring.

To solve these problems, in the Multiline™ device we use the method of “dot” coagulation of the pigmented spots. The method is based on the principle of coagulation of tissues located between the melanin grains. For different concentrations of melanin we select different parameters of laser radiation, which permits tuning to an increased level of pigmentation for all skin photo types. To implement this method we use radiation in the form of a train of Q-sw pulses with optimised duration of the train and intervals between the pulses. As a result of such influence, areas with the given distance between the melanin grains, step by step heat up to the coagulation temperature. During this, all surrounding tissues effectively diffuse heat. It makes them not only coagulate, but even to reach the temperature which can cause production of additional melanin.
During the process of treatment, the pigmented spot becomes slightly darker. After one-two minutes an erythema appears which remains up to half an hour. Then for one-two weeks the treated spot has a more saturated colour and peels layer by layer (epidermal) or starts turning pale (dermal). The method permits the treatment of pigmental diseases on skin of any photo type without amplification of pigmentation, appearance of hypopigmentated areas. The risk of scarring in this case is zero.
The method is patented.