Capillary Malformation

Vascular Malformations

Therapy

Observation is appropriate for asymptomatic or mildly symptomatic hemangiomas of skeletal muscle and bone. If symptoms cannot be managed adequately by activity modification and nonnarcotic analgesics, further treatment may be considered. Embolization may be used to provide symptomatic relief of intramuscular hemangiomas.

When surgical excision is planned, embolization also may be used preoperatively to decrease intraoperative blood loss and postoperative recurrence. Excision of symptomatic intramuscular hemangiomas can provide permanent relief. However, because complete excision is required for long-lasting satisfactory results, this treatment option generally is restricted to hemangiomas contained within a single muscle belly. Even so, complete resection is not always possible; when incompletely resected, hemangiomas nearly always recur. In addition, surgery can be associated with large-volume blood loss, even when preoperative embolization is employed.

Laser knife excision of hemangiomas is a technique developed to better control intraoperative bleeding. Preoperative ultrasound-guided hookwire localization may aid in defining the extent of a hemangioma during excision.

Vascular malformations are localized or diffuse errors of development that may affect any segment of the vascular tree including arterial, venous, capillary, and lymphatic vessels. They are named on the basis of the predominant channel type and flow characteristics. Slow-flow anomalies include capillary, lymphatic, and venous malformations; fast-flow lesions include arteriovenous malformations and arteriovenous fistulae.

Capillary malformation (CM) is the proper name for "port-wine stain." These lesions consist of dilated capillary sized vessels in the superficial dermis with a paucity of normal nerve fibers. The lesion darkens with age due to vessel dilatation. CM may be confused with nevus flammeus neonatorum, which occurs in 50% of whites and is also known as “angel kiss” (on the forehead) or “stork bite” (on the nuchal area). Nevus flammeus neonatorum is due to a minor transient dilatation of dermal vessels that fades with age, whereas a CM does not (Image 9.5).

A	B
Image 9.5 A – Capillary malformation; B – Nevus flammeus neonatorum ("stork bite").

CMs affect 0,3% of infants with an equal sex distribution. Most CMs are sporadic, but some are inherited in an autosomal dominant pattern. They are present at birth and appear as flat, pink-red, cutaneous patches.

It may occur in any location and over time darkens and develops fibrovascular overgrowth.

It can be associated with soft tissue and skeletal hypertrophy. CM may signal an underlying structural abnormality. For example, a midline occipital CM can be associated with an encephalocele, whereas a CM over the spine may indicate a spinal dysraphism.

CM is also a common component of several combined VMs.

Treatment.The mainstay of treatment for CM is the flashlamp pulsed-dye laser (585 nm). This laser causes selective photothermolysis of CM via the chromophore oxyhemoglobin. The pulsed-dye laser does not penetrate more than 1.2 mm and results in lightening of the lesion in 70% of patients. Multiple sessions are often required.

The timing of therapy remains controversial. Some authors suggest that the ultimate results may be better when laser treatment is performed in infancy, whereas others do not believe that the age of treatment affects outcome. Initiating treatment before 6 months of age is an option and short-term follow-up appears promising.

Surgical intervention may be required for associated soft tissue hypertrophy and limb length discrepancy.