LVI Congenital Webs, Cysts, Laryngoceles and other Anomalies of the Larynx

Abstract

Commonest of all congenital anomalies of the larynx is laryngomalacia. This anomaly is characterized by a gradually increasing stridor during the 1st year of life which spontaneously decreases in intensity and disappears 6 months to a year later. Stridor is the principal symptom of all obstructions of the airway and must be accurately identified to differentiate it from other conditions characterized by stridor. Other cartilaginous anomalies are absence of the epiglottis and deformities of the cricoid such as a stenotic cricoid ring and a laryngo-esophageal cleft. Cysts and laryngoceles are encountered originating near the ventricle of the larynx. Internal laryngoceles protruding from between the true and false cords and those bulging within the aryepiglottic fold generally have some con- nection with the interior of the larynx. Glottic cysts and internal thyroglossal duct cysts do not have actual or potential communication with the interior of the larynx. Webs may be a supraglottic fusion of the false cords, glottic membranes between the true cords, or fusion of the anterior portion of the true cords, or subglottic webs which are membranous, distinct from cartilaginous cricoid obstruction. Congenital glottic atresia is rarely seen because only if immediately recognized at birth and relieved at once can the infant survive. Sub-glottic stenosis, a thickening of the subglottic structures, is common and accounts for many cases of recurring "croup" or prolonged ex-tubation in infants tracheostomized because of the respiratory obstruction early in life. Bilateral laryngeal paralysis is associated with cerebral retardation, a meningomyelocele or extensive birth trauma. Unilateral left cord paralysis may often be traced to anomalies of the heart or great vessels, the esophagus or the tracheobronchial tree. Unilateral right cord paralysis may be seen in an otherwise normal infant. The voice (cry) of an infant with bilateral recurrent laryngeal nerve paralysis is more normal than one with a unilateral paralysis; but inspiration is stridorous and a large % require trachestomy. Vascular anomalies consist of hemangiomas and lymphangiomas, the former as capillary and cavernous, usually associated with other hemangiomas about the head and neck, the latter as laryngeal extensions of a cystic hygroma.