Vascular anomalies are conditions involving abnormal development of blood vessels or lymphatic vessels. Many are visible at birth or during the first year of life, although some only become noticeable later when they grow, change colour, cause pain, or interfere with function. Most vascular anomalies are benign, but some can be complex and require ongoing care. Early assessment and the correct diagnosis is so children receive the right treatment at the right time.
Classification
The ISSVA (International Society for the Study of Vascular Anomalies) classification divides vascular anomalies into two major groups:
Vascular Tumours
These are lesions that show abnormal cellular growth. The most common example is the infantile haemangioma, which grows rapidly in early infancy and then slowly shrinks over time.
Vascular Malformations
These are structural vessel abnormalities present at birth. They grow proportionally with the child and do not regress.
Within this category there are: capillary malformations, venous malformations, lymphatic malformations and arteriovenous malformations,
The ISSVA system ensures accurate diagnosis and guides appropriate treatment.
The common vascular anomalies that are encountered in children include:
Infantile Haemangiomas
These soft, bright red or blue lesions typically appear in the first few weeks of life and were previously known as strawberry naevi. They often start as a faint pink patch before rapidly becoming more raised and vividly coloured. Infantile haemangiomas follow a very predictable natural history. They undergo a proliferative (growth) phase during the first 3-6 months of life, where they may enlarge quickly in size and thickness. A slower growth phase may continue up to around 9-12 months. After this, they enter an involution phase, where the lesion gradually softens, lightens in colour, and shrinks over several years. By school age, many haemangiomas have significantly improved, although some may leave behind residual skin laxity, telangiectasia (small visible vessels), or a subtle contour irregularity. Most haemangiomas are completely harmless, however some can ulcerate, bleed, obstruct vision, cause nasal or airway blockage, or interfere with feeding, depending on their size and location. Haemangiomas in the eyelids, nose, lip, beard area (lower face and neck), or central face are more likely to cause complications and often require earlier treatment.
Treatment
The first-line therapy is a medication called propranolol, which is highly effective when started early, ideally within the first year of life, and usually continued until around 12 months of age to prevent rebound growth. Propranolol prevents proliferation of the lesion and reduces the risk of ulceration.
While medication has greatly reduced the number of haemangiomas requiring surgery, there is still an important role for surgical treatment, particularly after the haemangioma has finished involuting. Surgery may be considered when there is persistent bulky tissue or excess skin after involution or if the lesion causes long-term distortion of the lip, nose, or eyelid. Sometimes early excision is required if there is a functional problem.
Capillary Malformations
Usually appearing as flat pink or red patches (port-wine stains), they can occur anywhere on the body. Over time they may darken, thicken, or develop small nodules. Depending on location, they may be associated with underlying syndromes or structural changes.
Treatment
Pulsed dye laser remains the mainstay treatment to lighten the colour and reduce long-term thickening.
Venous Malformations
Venous malformations appear as soft, compressible blue or purple lesions that may enlarge with crying or activity. They can occur in the skin, muscles, joints, or internal organs. Symptoms include pain, swelling, distortion of nearby structures, and formation of small clots (phleboliths) that can cause tenderness.
Treatment
Sclerotherapy is the primary treatment, shrinking the malformation through targeted injections. Electrosclerotherapy may be used for small or superficial areas. Surgery is considered in selected cases, often after sclerotherapy.
Lymphatic Malformations
These fluid-filled cystic lesions often occur in the head and neck but can appear anywhere. They may be macrocystic (large cysts), microcystic (tiny clusters), or mixed. Symptoms include swelling, recurrent infections, discomfort, leakage of lymphatic fluid, and sudden enlargement due to bleeding or infection.
Treatment: Sclerotherapy is first line for macrocystic lesions, while microcystic areas may benefit from electrosclerotherapy. Surgery may be suitable for well-defined or functionally problematic lesions and generally involves excising or debulking malformation itself.
Arteriovenous Malformations
These are warm, pulsatile lesions caused by abnormal connections between arteries and veins. They may appear as red patches with visible vessels and can cause swelling, pain, ulceration, bleeding, or tissue destruction over time. They often progress during later childhood or adolescence.
Treatment
Pre-operative embolisation is essential to block blood flow and reduce bleeding risk before any surgery. A combined approach with interventional radiology and surgical excision offers the best outcomes.
