How can pigmentation disorders be treated with lasers?

The correct answer focuses on the mechanism of how lasers can effectively treat pigmentation disorders. Lasers operate by emitting concentrated light energy that targets specific chromophores in the skin, such as melanin, which is responsible for pigmentation. By directing the laser at areas with excess melanin, the treatment helps to break down these pigment particles. This breakdown allows for the body's natural processes to gradually remove the excess pigment, thereby reducing the appearance of pigmentation disorders like melasma, sunspots, or age spots.

In contrast, other treatments mentioned do not directly address the excess melanin in the same targeted manner. For instance, injecting steroids is typically used for inflammatory skin conditions rather than directly treating pigment issues. Topical retinoids can improve skin texture and promote cell turnover but do not specifically target melanin in the way lasers do. Oral medications may address underlying conditions or inflammation but are not the primary method for treating localized pigmentation problems. Thus, the mechanism of targeting and breaking down excess melanin is key to effectively addressing pigmentation disorders with lasers.