Content area
Full text
Otitis media with effusion (OME) is characterized by the occurrence of fluid in the middle-ear cavity in the absence of any signs of acute ear infection and occurs most frequently in children with auditory or eustachian tube dysfunction. Its chronic form is an important clinical issue for pediatricians and otologists alike. The study by Depreux et al. in this issue of the JCI shows that absence of the transcriptional activator Eya4 in knockout mice results in abnormal structuring of the eustachian tube, thus predisposing these animals to OME (see the related article beginning on page 651). The development of this genetics-based animal model is an important advance for understanding OME and for exploring new avenues of treatment.
Nonstandard abbreviations used: ET, eustachian tube; Eya4, eyes absent 4 homolog; OME, otitis media with effusion.
In humans, fluid accumulation in the middle-ear cavity, in the absence of acute ear infection, is known as otitis media with effusion (OME) (1-3). The disorder occurs most frequently in children, with approximately 2.2 million episodes diagnosed each year in the United States (2,3). Fortunately, spontaneous resolution occurs within three months in a large number of these children. Unfortunately, an equally large number of children have recurrent OME (1). Recurrent OME is accompanied by an increased risk for sustained conductive hearing loss, with the potential for speech, language, and learning problems. The treatment of chronic OME is thus an important clinical issue for pediatricians and otologists.
The most important factor associated with OME is abnormal structure and function of the eustachian tube (ET) (3). The ET is an osteocartilaginous tube that connects the middle-ear cavity to the nasopharynx. The cartilaginous portion opens into the nasopharynx at the torus tubarius, and the osseous portion opens into the anterior wall of the middle-ear cavity at the ostium (3) (Figure 1A). The lumen of the ET and the inner surface of the middle-ear cavity are lined with the respiratory epithelium. The mucosal layer of the respiratory epithelium consists of secretory cells, ciliated cells, supporting cells, and connective tissue (3). The ET serves two major functions. First, it permits air to enter or leave the middle-ear cavity, thus balancing middle-ear pressure with ambient air pressure (4). The tensor veli palatini muscle is primarily responsible for...