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By Emily Perry 28 February 2010 Tissue that grows over the glottis and between the vocal folds. A laryngeal web growing across the glottis between the two vocal folds inhibits normal fold vibration, often producing a high-pitched rough sound during vibration. Webs can be present at birth or acquired. If present at birth, it is detected at the time of birth, and is the result of the glottal membrane failing to separate in embryonic development. Depending on the size of the web, the baby will produce stridor (inhalation noises), shortness of breath, and often a different high-pitched cry. Approximately three-fourths of all laryngeal webs cross the glottis. The presence of webbing at birth requires immediate surgery. Usually, the infant’s larynx will recover over a period of four to six weeks. Acquired webs result from some kind of bilateral trauma or medial edges of the vocal folds. Anything that might serve as an irritant to the mucosal surface of the folds may be in the initial cause of the webbing. Any surface irritation due to prolonged infection or trauma may cause the inner margins of the two fold surfaces to grow together. To explain further, one principle of plastic surgery is that, when approximated together, offended tissue surface will tend to grow and fuse together. The same principle explains why webbing occurs. The offended surface of the two approximated folds tends to grow together, in this case forming a thin membrane across the glottis. Webbing grows across the glottis in an anterior to posterior fashion. Severe laryngeal infections sometimes cause enough glottal irritation to lead to web formation. Bilateral surgery of the folds, perhaps for papilloma and nodules can also be followed by a web. External trauma to the folds, such as a direct hit on the thyroid cartilage that causes it to fracture, may damage the folds behind it, thus creating enough glottal irritation for a web to develop. Laryngeal or tracheal surgery is the most frequent event producing the postsurgical acquired web. Laryngeal web may cause severe dysphonia as well as shortness of breath, depending on how extensively the webbing crosses the glottis. The treatment for the formation of webbing is surgery. The webbing is cut, freeing the two folds. To prevent the surgically removed web from growing again, a vertical keel is placed between the two folds and kept their until complete healing has been achieved. A keel is about the size of a fingernail and is put between the vocal folds, preventing them from approximating. The patient is then on vocal rest as long as the keel is in place, because it presence inhibits normal fold vibration. When the keel is removed, often in six to eight weeks, the patient generally requires some voice therapy to restore normal phonation. If there was extensive damage to the larynx from the trauma, it may well be impossible after healing and voice therapy to ever develop the same kind of normal voice the patient had before the accident. The prognosis for voice recovery after webbing and its surgical treatment is highly individualized , depending on the extent of the trauma and size of the web. Leukoplakia are whitish patches that are lesions to the surface membrane of mucosal tissue and that often extend beneath the surface in subepithelial space. The primary etiology of these white patches is continuous irritation of membranes. The most common cause is heavy smoking. Although the lesions are classified as benign tumors, they are considered precancerous lesions and must be followed closely. Within the vocal tract, common sites of leukoplakia are under the tongue and on the vocal folds. It is important to note that it is difficult or impossible to distinguish between leukoplakia and cancer of the larynx by visual inspection along. Although leukoplakia on or under the tongue have only minimal effects on voice, leukoplakia on the vocal folds dramatically alter voice. The added lesion mass to the vocal folds lowers voice pitch and frequently causes hoarseness and sometimes hypophonia. Also, because leukoplakia are random in size and location, they often cause the vocal folds to be asymmetrical, which may result in diplophonia as each fold vibrates at a different frequency because of its different size or mass. Leukoplakia that occupies space on the glottal margin may prevent optimal approximation of the folds, contributing to breathiness, reduced loudness, and overall dysphonia. The treatment of leukoplakia is medical-surgical , and voice therapy only contributes to developing the best voice possible .
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