1 What is the problem?
Vascular lesions are visible blood vessels: facial thread veins (telangiectasia), rosacea redness, cherry angiomas and port-wine stain birthmarks.
2 The science
Oxyhaemoglobin in red blood cells absorbs yellow-green light strongly. The heat spreads to the vessel wall and seals (coagulates) it; the body then absorbs the closed vessel. The pulsed dye laser was the first laser designed using selective photothermolysis.
3 Key points to remember
- Yellow light (585–595 nm) targets haemoglobin
- 1064 nm reaches deeper, larger veins
- Purple bruising (purpura) can occur after treatment
- Port-wine stains respond best when treated early
4 What happens during treatment
- 01
Vessels are examined
- 02
Eyes protected, skin cooled
- 03
Pulses trace the vessels
- 04
Cold compress and sun protection
5 Possible risks
Bruising, swelling, blisters and pigment change. Correct settings, skin cooling and experienced hands reduce these risks.
Did you know? Port-wine stains in children were among the first conditions treated with lasers designed for skin.