A 35 year old female presents with intermittent discharge from her right ear whenever she has an upper respiratory tract infection or gets her ears wet. She has started to notice declining hearing in the same ear over the past two years. The patient has a medical history of recurrent ear infections as a child. On examination, she has a large perforation of the eardrum with inflamed middle ear mucosa as well as conductive hearing loss on tuning fork testing.
Tympanic membrane perforations are holes in the eardrum that most commonly occur as a consequence of either ear infections or trauma to the ear. Acute middle ear infection (acute otitis media) is a common condition occurring at least once in 80% of children. Most acute otitis media resolves with spontaneous discharge of infected secretions through the eustachian tube into the nasopharynx. Occasionally, when there is significant eustachian tube obstruction — commonly from immaturity of the tube or from adenoid hypertrophy — then there may be resolution of the infection by perforation of the tympanic membrane.
Most acute tympanic membrane perforations from infection spontaneously resolve with treatment of the infection. Occasionally, when the infections are frequent, there is extensive scarring (tympanosclerosis) of the eardrum and middle ear. This compromises the blood supply to the healing eardrum and, occasionally, stops the hole from healing. These patients often have discharging ears when there is water exposure or with upper respiratory tract infections.
With frequent ear infections in children that fail to resolve with medical therapy, grommets (middle ear ventilation tubes) are sometimes recommended by the ENT surgeon. The grommet tube reduces the frequency and severity of ear infections by ventilating the middle ear and bypassing a blocked eustachian tube. Rarely, when the grommet tube falls out, or when it is removed, the hole in the eardrum does not heal spontaneously. This is typically due to persistent eustachian tube dysfunction and tympanosclerosis, causing poor blood supply to the healing eardrum. Traumatically induced holes occur from a rapid compression of the air column in the external ear canal, most commonly from a blow to the side of the head. In the Australian population this occurs most frequently with water skiing or surfing accidents, or in children with accidental blows to the side of the head.
Examination of the ear is divided into anatomical inspection (otoscopic and microscopic) and physiological assessment (clinical hearing and balance testing). A tympanic membrane perforation is diagnosed when a deficiency in the eardrum is noted. The location of the perforation in the eardrum is clinically relevant. The pars flaccida region of the tympanic membrane is that region above the short process of the malleus.