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What is Vascular malformation and explain in detail?
A vascular malformation is a blood vessel or lymph vessel abnormality. Vascular malformations are one of the classifications of vascular anomalies, the other grouping is vascular tumors. They may cause aesthetic problems as they have a growth cycle, and can continue to grow throughout life.
Vascular malformations of the brain (VMBs) include those involving capillaries, and those involving the veins and arteries. Capillary malformations in the brain are known as cerebral cavernous malformations or capillary cavernous malformations (CCMs). Those involving the mix of vessels are known as cerebral arteriovenous malformations (AVMs or cAVMs). The arteriovenous type is the most common in the brain.

Types
A simple division of the vascular malformations is made into low-flow and high-flow types. Low-flow malformations involve a single type of blood or lymph vessel, and are known as simple vascular malformations; high-flow malformations involve an artery. There are also malformations that are of mixed-flow involving more than one type of vessel, such as an arteriovenous malformation.Low-flow vascular malformations include capillary malformations, venous malformations, and lymphatic malformations.

Capillary malformation
Capillary malformations involve the capillaries, and are the most common type. They used to refer only to port-wine stains but now include others. Capillary malformations are limited to the superficial layers of the skin but they can thicken, become nodular, and sometimes become disfiguring.
It has been proposed that the category of capillary malformations, also called vascular stains, be classified into seven major clinical types including nevus flammeus nuchae also known as nevus simplex, commonly known as stork bite or salmon patch.A capillary malformation is also a feature of the disorder macrocephaly-capillary malformation.

Venous malformation
Venous malformations are typically ill-defined masses, coloured from pale to dark blue. They can affect any tissue in the body