The type and shape of the foreign body, its location, and the patient's level of cooperation will determine which piece of equipment to use. Multiple options exist for the removal of EAC foreign bodies. Another important anatomic feature of the EAC is the potential blind spot in the tympanic sulcus caused by the oblique slope of the tympanic membrane anteroinferiorly as it nears the bulge of the temporomandibular joint. Of significant importance for foreign body management, the EAC has two natural narrowings: the first narrowing is at the bony-cartilaginous junction, and the second is just lateral to the tympanic membrane. As a result, in adults, pulling the helix posterior and superior straightens the EAC and allows for better visualization of the tympanic membrane. The EAC assumes a gentle sigmoid contour in adults, with the cartilaginous portion angling posteriorly and superiorly and the bony portion coursing anteroinferiorly. The external auditory canal is nearly straight in children, becoming adult-sized - approximately 2.5 cm long - at about nine years of age. Cranial nerves VII and IX also contribute, but to a lesser extent skull base lesions that involve the facial nerve may cause numbness of a portion of the EAC, and this phenomenon is known as the Hitzelberger sign. Arnold's nerve is the pathway that results in coughing or gagging in some patients with instrumentation of the EAC. Innervation of the EAC is mainly supplied by cranial nerves V3 (mandibular branch) and X, the latter via a small branch known as Arnold's nerve. The skin lining the cartilaginous portion of the EAC has hairs and modified sweat glands that secrete cerumen (earwax). The medial two-thirds of the EAC is comprised of bone covered with stratified squamous epithelial skin, while cartilage makes up the skeleton of the outer third. The EAC and the outer layer of the tympanic membrane arise from the first branchial cleft. However, for most inorganic objects, removal from the EAC is not emergent, although, in cases of prolonged retention of foreign bodies, significant edema of the EAC may render removal more challenging and painful. Certain types of foreign bodies, such as button batteries, do require emergent removal. There may also be a slight male predominance, but not all authors agree on this point. These combine to account for just over half of the foreign bodies removed in one study. The most commonly removed foreign bodies include beads (most common), paper or tissue paper, and popcorn kernels. While more common in pediatric patients, adults may also present with EAC foreign bodies, ranging from insects to hearing aid pieces and cotton balls. This article aims to provide physicians with an understanding of the scope of the problem as well as information regarding methods for managing a foreign body in the external auditory canal. Depending on the specialty and location of practice, some doctors will encounter this condition more frequently. Many physicians who work in acute care settings, especially those who see pediatric patients, will encounter foreign bodies in the external auditory canal. Pharyngeal foreign bodies are most common in the adult population, however, making up 17% of cases. The external auditory canal (EAC) is the most common location to encounter a foreign body, particularly in children, accounting for 44% of cases, with nasal, pharyngeal, esophageal, and laryngobronchial locations representing 25%, 23%, 5%, and 2% of cases, respectively.
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