Haemangioma

Definition

noun, plural: haemangiomas or haemangiomata

An arteriovenous malformation that consists of a benign tumour and is mostly congenital, caused by improperly angioblastic tissue in the foetus


Supplement

Haemangioama is a congenital arteriovenous malformation. It consists of a benign tumour containing newly formed blood vessels with an abnormal communication between the arterial and venous systems. It results when there is an improperly formed angioblastic tissue in the fetus. It is red or purple discolouration vascular markings on the skin that develop shortly after birth. It may also form in subcutaneous tissues. Localised steroid injections have been used successfully to reduce the size of a birthmark.

If large enough, they may produce a shunt of sufficient magnitude to raise the cardiac output. Arteriovenous malformations may occur in brain, brainstem and spinal cord, where they may cause headaches, seizures or bleeding (subarachnoid haemorrhage).

Most are usually painless and benign. Some lesions, particularly in cavernous haemangiomas, will disappear or become harder to see as the child approaches school age (i.e. about the age of 9 years). It is commonly found in the head, neck, and visceral organs (e.g. liver, spleen, or pancreas). In strawberry haemangioma, the lesions appear as raised, red, lumpy area of flesh. It is the most common form of haemangioma. It affects mostly female, especially premature and low birth weight infants. The lesions may be gone by the age of 2 or by the time of the child's school age.


Word origin: Greek haema- ("blood") + angeio ("vessel") + -oma ("tumor")

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