Q-switched lasers generate regular pulse trains via repetitive Q switching. It is due to this technique of Q switching that the principle of selective photothermolysis can be applied to the pigmented lesions to achieve the desired clinical results without much damage to the surrounding area.
The search for an ideal laser for pigmented lesions has been long and continuing. It started with the ruby and carbon dioxide in continuous mode with heavy and bulky lasers systems which were not practical to use. Moreover, the complications/side effects far outweighed the benefits. Today, we stand tall with new Q-switched technology which delivers a flat top beam to utmost perfection and at the same time sparing the surrounding skin. But does that end our quest for ideal laser for pigmented lesions? We still can’t treat melasma effectively. There are still problems like scarring, ghost shadows, etc. with tattoos.
There is still apprehension in using frequency doubled Q-switched laser 532 nm in Asians skins due to fear of hyperpigmentation. Hence, there is definitely still a long learning curve ahead to overcome these lacunae in the application of the existing technology to common skin problems. However, in Q-switched technology, we certainly have found answers to some of the previously untreatable conditions. Nevertheless, newer future developments overcoming the shortcomings of the existing ones would certainly be welcome.
Various clinical applications of q switch lasers are tattoos, pigmented lesions like lentigenes, café au lait macules, freckles , dermal pigmented lesions like nevus of ota, ABNOM, etc, non-ablative resurfacing of wrinkles and scars, laser assisted hair reduction, medium depth non ablative skin resurfacing, melasma , vascular lasers and dark lips.