Photoaging refers to the damage that is done to the skin from prolonged exposure, over a person's lifetime, to UV radiation. Sun freckles (also known as liver spots, although they have nothing to do with the liver), irregular pigmentation and dilated blood vessels (often referred to as "broken" blood vessels) are some examples. Other examples of photoaging include fine lines and laxity from the loss of elastic fibers and healthy collagen.
To understand the difference between photoaged vs non-photoaged skin, look no further than your arms and chin. Notice how the inside surface of your upper arm is lighter in tone? Compare this to the outside of your arm where you can see the sun's staining effect. Similarly, you can see these effects on your neck if you look in a mirror. Given enough sun exposure to the surrounding areas, there will be a subtle and even "V" outlined below your chin where the skin has been shielded from the sun by your chin. The mottled pigmentation of the sides of the neck is missing because your chin acts as a sunbrella.
Your best weapon in the treatment of photoaging is of course prevention through good sun protection. There"s also a variety of ways to reverse signs photoaging, including topical treatments such as vitamin A derivatives, alpha hydroxy acids, vitamin C preparations, plant and botanical derivatives, antioxidants, growth factors and peptides. Chemical peels and microdermabrasions are also options worth looking into, as well as laser surgery and radiofrequency devices which help correct sun freckles, dilated blood vessels and wrinkles. Botox, collagen, hyaluronic acid and fat injections can help with certain lines of expression and loss of facial fullness. And new non-invasive tightening devices have come to the forefront to "replace" face-lifts.
Speak with your dermatologist to find out which treatments are best for you.