Chapter 6 Special Sensory Organs: Eye and Ear 263 Otitis Media Otitis media (ō-TĪ-tĭs MĒ-dē-ă) is a bac- terial or viral infection of the middle ear (Figure 6.8). It is more common in children than adults. The otalgia (ō-TĂL-gē-ă), or ear pain, that accompanies otitis media is due to inflammation and buildup of fluid in the middle ear. Persistent ear infections can cause hearing problems and other seri- ous complications. Presbycusis Presbycusis (PRĔZ-bē-KŪ-sĭs) is the gradual loss of hearing that occurs as people age. Although there is no single known cause for presbycusis, it is most commonly associated with degenerative changes to the inner ear. One of the hall- marks of presbycusis is difficulty hearing high-frequency sound, such as that pro- duced by someone talking, particularly amid background noise. Genetic factors as well as repeated or prolonged exposure to loud noises can contribute to age-related hearing loss. Procedures and Treatments We will now briefly review common diagnostic tests and procedures used to help identify disorders and diseases of the eyes and ears, as well as some common therapeutic treatments. The Eye A variety of procedures are used to test visual acuity and help diagnose diseases and disorders of the eye, and rapidly developing technologies have brought about cutting-edge treatments. For the purpose of this brief overview, we will present a few common procedures and treatments. Visual Acuity Test The visual acuity (ă-KYŪ-ĭ-tē) test is a routine part of an eye examination. The Snellen chart, a standardized eye chart, is used to assess eyesight clarity and detect problems with vision (Figure 6.9). Eustachian tube A. Normal middle ear B. Otitis media Infected fluid in middle ear Eardrum Auditory bones Figure 6.8 Middle ear infection