Ear Problems - Otitis Media
Determination of whether otitis media is present can be made visually – by careful examination of the ear drum, similar to when a physician examines a human’s ear. Use of a standard otoscope, similar to what is used by a physician for routine ear examination in humans, is a good screening tool. Use of video-endoscopic equipment such as what is used by Dr. Byrne, provides better visualization than with a standard otoscope. It is not unusual for discharge to be adhered to the surface of the ear drum and the video otoscope provides superior visualization, allowing material to be scraped away more safely.
Advanced imaging modalities such as computed tomography (CT) scan or magnetic resonance imaging (MRI) can be utilized to look for abnormalities such as fluid within the middle ear if direct examination is not feasible. These imaging techniques also require general anesthesia.
If otitis media is severe, sometimes surgical drainage of the middle ear via an incision in the skin, of the neck below the ear, is necessary. This is a delicate procedure and requires experience to safely, many important nerves and blood vessels are near the middle ear.
Otitis media, as opposed to otitis externa or otitis interna, involves inflammation of the middle ear structures. It is usually due to extension of infection from the external ear canal or to penetration of the tympanic membrane by a foreign object. Extension of infection through the auditory tube also occurs in cats, explaining why the most common cause of otitis media is chronic respiratory infection or chronic sinusitis. Hematogenous spread of infection to these areas is possible but rare. Otitis media can lead to otitis interna and inflammation of the inner ear structures and can result in loss of balance and deafness.
The signs of otitis media and otitis externa may be similar. Head shaking, rubbing the affected ear on the floor, and rotating the head toward the affected side are usually present. The ear is usually painful, with a discharge and inflammatory changes in the ear canal.
Because of the possibility of hearing loss and damage to the vestibular apparatus, long-term (3-6 wk) systemic antibacterial therapy should be instituted as soon as the diagnosis of otitis media is made. Otitis media with an intact tympanum usually responds well to systemic antibiotic therapy; however, if chronic otitis externa exists and the tympanum is ruptured, the chances of successful treatment are reduced. If facial and sympathetic nerve deficits develop, they may persist even after the infection has been cleared.