A haemangioma is an arteriovenous malformation or proliferation of abnormal blood vessels.
A strawberry naevus or capillary cavernous haemangioma is a raised nodular patch of strawberrycoloured skin, which can appear anywhere on the body. They usually develop in the first few weeks of life, grow to a maximum in the first year and then gradually resolve. Treatment is not required unless they involve the eye, bleed or become recurrently infected. Treatments include laser therapy and courses of steroids.
Cavernous haemangioma are larger and deeper vascular lesions, which may be covered by normal skin.
Large haemangiomas can trap platelets leading to thrombocytopenia (Kasabach–Merritt syndrome).
Port-wine stains are irregular reddish-purple macules caused by permanent vascular dilatation, which may darken and become irregular with age. They are treated with laser therapy. A port-wine stain in the ophthalmic division of the trigeminal nerve may have an associated vascular malformation in the brain or meninges leading to epilepsy, hemiplegia and developmental delay (Sturge–Weber syndrome).
Pyogenic granuloma is an acquired haemangioma consisting of a bright red or blood-crusted nodule, which often follows trauma. Surgical curettage is possible but they occasionally recur.