Rarely, impingement upon critical organs may result in complications, such as respiratory distress when a lymphangioma compresses the airway.

They are distinguished by the depth and the size of abnormal lymph vessels, but all involve a malformation of the lymphic system.

[9] In 1976, Whimster studied the pathogenesis of lymphangioma circumscriptum, finding lymphatic cisterns in the deep subcutaneous plane are separated from the normal network of lymph vessels.

Whimster theorized the cisterns might come from a primitive lymph sac that failed to connect with the rest of the lymphatic system during embryonic development.

[citation needed] A thick coat of muscle fibers that cause rhythmic contractions line the sequestered primitive sacs.

Rhythmic contractions increase the intramural pressure, causing dilated channels to come from the walls of the cisterns toward the skin.

[7] Microscopically, the vesicles in lymphangioma circumscriptum are greatly dilated lymph channels that cause the papillary dermis to expand.

[7] The typical history of Lymphangioma circumscriptum shows a small number of vesicles on the skin at birth or shortly after.

Usually, lesions are asymptomatic or do not show any evidence of a disease, but, mostly, patients may have random break outs of some bleeding and major drainage of clear fluid from ruptured vesicles.

[citation needed] Cavernous lymphangioma first appears during infancy, when a rubbery nodule with no skin changes becomes obvious in the face, trunk, or extremity.

Other imaging methods such as CT and MRI scans are useful in treatment planning, delineate the size of the lesion, and determine its surrounding vital structures.

Lymphangioma circumscription can be healed when treated with a flashlamp pulsed dye laser, although this can cause port-wine stains and other vascular lesions.

[15] Orbital lymphangiomas, which carry significant risks from surgical removal, can also be treated with sclerosing agents, systemic medication, or through observation.

A sclerosing agent, such as 1% or 3% sodium tetradecyl sulfate, bleomycin, doxycycline, or ethanol, may be directly injected into a lymphocele.

"All sclerosing agents are thought to work by ablating the endothelial cells of the disrupted lymphatics feeding into the lymphocele.

Treatment with sirolimus can decrease pain and the fullness of venous malformations, improve coagulation levels, and slow the growth of abnormal lymphatic vessels.

Two cases of lymphangiosarcoma arising from lymphangioma circumscriptum have been reported; however, in both of the patients, the preexisting lesion was exposed to extensive radiation therapy.

[citation needed] In cystic hygroma, large cysts can cause dysphagia, respiratory problems, and serious infection if they involve the neck.

In 1965, Bill and Summer proposed that Cystic hygromas and lymphangiomas are variations of a single entity and that its location determines its classification.