Port wine stains are caused by abnormal development of blood vessels (capillaries) and last a lifetime. The port-wine stain (also known as nevus flammeus) appears as a flat, pink, red or purple mark, and occurs on the face, trunk, arms, or legs.
If you or your child has a port wine stain present on eyelids, this is thought to pose an increased risk of glaucoma, an eye disease associated with increased pressure in the eyes that can lead to blindness if it's not treated. Read more about port-wine stains, birthmarks, and other abnormal skin pigmentation.
Visual Guide to Birthmarks
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