Cystic hygromas, however, account for approximately 90% of the lymphangiomas in the head and neck region. These three types are frequently found together in a same patient, depending on the severity of the disease. When a lymphangioma is confined to fairly dense tissue, such as the tongue, it presents as a cavernous lymphangioma, but when it develops in the relatively loose fascia of the neck, a cystic lesion occurs. A commonly used classification classifies these lesions into capillary lymphangioma or lymphangioma simplex, cavernous lymphangioma, and cystic lymphangioma or cystic hygroma 4. Bill and Summer, in 1965, presented the concept that cystic hygromas and lymphangiomas are variations of a single entity and that its classification is determined by its location in the head and neck 3. Lymphangiomas are classified as microcystic (capillary lymphangiomas), macrocystic (cavernous lymphangiomas) and cystic hygromas according to the size of the lymphatic cavities incorporated 2. The first suggests that a blockage or arrest of normal growth of the primitive lymph channels occurs during embryogenesis, the second that the primitive lymphatic sac does not reach the venous system, while the third advances the hypothesis that, during embryogenesis, lymphatic tissue lays in the wrong area 1. Three theories have been proposed to explain the origin of this abnormality. They consist in localized centres of abnormal development of the lymphatic system.
Lymphangiomas are rare congenital benign lesions occurring mainly in the head, neck and oral cavity.
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