Telangiectasia are small dilated blood vessels near the surface of the skin; typically, they measure only a few millimeters. They can develop anywhere on the body but are frequently found on the face around the nose, cheeks, and chin.

Since telangiectasias are vascular lesions, they blanch when tested with diascopy.

Telangiectasias are generally treated with laser or IPL therapy. There have been medication based treatments available for the last 50 years. Laser therapy uses light beam that is pulsed onto the veins in order to seal them off, leading them to dissolve.

Telangiectasias can lead to naevus flammeus (port-wine stain), which is a flat birthmark on the head or neck that spontaneously regresses. A port-wine stain, if present, will develop proportionately with the child.

There is a high association with Sturge-Weber syndrome, a nevus formation in the skin provided by the trigeminal nerve and associated with glaucoma, meningeal angiomas, and mental retardation. Finally, spider telangiectasias are a radial array of tiny arterioles that commonly arise in pregnant women and in patients with hepatic cirrhosis and are associated with palmar erythema.