Primary Care Otolaryngology

Chapter 2

larynx, hypopharynx, and nasopharynx. Fiberoptic instruments provide a similar ability to examine these regions, but with superior optics. The Ear Assess the external auricle for congenital deformities, such as microtia, promin auris, or preauricular pits. The external auditory canal should be examined by otoscopy after being thoroughly cleaned if it is blocked by cerumen. The canal should be assessed for swelling, redness (erythema), narrowing (stenosis), discharge (otorrhea), and masses. The tympanic membrane is normally pearly gray, shiny, translucent, and concave. Changes in the appearance of the eardrum may indicate pathology in the middle ear, mastoid, or eustachian tube. White patches, called tympano- sclerosis , are often clearly visible and provide evidence of prior significant infection. An erythematous, bulging, opacified tympanic membrane indi- cates acute bacterial otitis media. A dull, retracted, amber eardrum can be a sign of serous otitis. If a perforation is present, then the middle ear mucosa may be viewed directly. Healed perforations are often more trans- parent than the surrounding drum and may be mistaken for actual holes. Pneumatic otoscopy should be performed to observe the mobility of the tympanic membrane with gentle insufflation of air. Mobility may be lim- ited by scarring, middle ear effusion, or perforation. Eustachian tube func- tion may be assessed by watching the eardrum as the patient executes a gentle Valsalva. Tuning forks can be used to grossly assess hearing and to differentiate between conductive and sensorineural hearing loss. A tuning fork placed in the center of the skull ( Weber test ) will normally be perceived in the mid- line. The sound will lateralize and be perceived as louder on the affected side in cases of conductive hearing loss. If a sensorineural loss exists, the sound will be perceived in the better or normal hearing ear. The tuning fork is then placed just outside the external auditory canal for the Rinne’s test of air conduction hearing. Placing the base of the tuning fork over the mastoid process allows bone conduction hearing to be assessed. In conduc- tive hearing loss, the tuning fork is heard louder behind the ear (bone con- duction is better than air conduction in conductive hearing losses). A proper, complete assessment of hearing requires audiometry . This is indicated in any patient with chronic hearing loss, or with acute loss that cannot be explained by canal occlusion or middle ear infection. It is also an integral part of the evaluation of the patient with vertigo.

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Primary Care Otolaryngology