Many patients presenting to a clinician with a possible vestibular disorder have underlying auditory impairment. Because the ear houses the sensory organs for auditory and vestibular input, not surprisingly many otologic disorders (e.g., Ménière's disease, perilymphatic fistula, labyrinthitis, acoustic neuroma, and others) give rise to both auditory and vestibular symptoms. An understanding of clinical methods of assessment and management of hearing loss and tinnitus is beneficial for the clinician who must diagnose and treat patients with vestibular impairment.
History and Physical Examination
A thorough assessment of a patient's auditory system requires obtaining information from a careful history and physical examination, as well as from audiological testing. A patient whose chief complaint is one of disabling dizziness may not volunteer information about a mild hearing difficulty, particularly one with an insidious onset. At the time of the initial clinical assessment, the examiner should grossly assess hearing acuity of any patient presenting with possible vestibular impairment, especially if audiological testing has not yet been performed. Obtaining a formal audiological assessment on patients with vestibular hypofunction would be a high priority. Inquiry should be made as to whether the patient has subjective hearing difficulties, and if so, in what environments is hearing most challenging. Information such as whether the patient can still talk on the telephone with either ear or whether they frequently need to ask for speakers to repeat themselves can be indicative of worsening hearing. For more subtle hearing losses, the patient may report problems only in certain situations such as listening in church or communicating in a noisy environment such as a restaurant.
The simplest method for identifying gross hearing impairment is for the examiner to occlude one external canal by pressing inward on the tragus and assessing whether the patient can hear a vibrating tuning fork, a whisper, or the examiner's fingers rubbing together near the other ear. An asymmetric hearing loss can sometimes be identified by the Weber tuning fork test, which entails placing a vibrating 512-Hz tuning fork firmly on the patient's forehead or teeth and determining whether the patient perceives the sound emanating from the midline (Fig. 13.1). If sound perception lateralizes to one side, then hearing loss is present. To determine which ear has the loss, the examiner can next perform a Rinne test with the fork (Fig. 13.2). To do this test, the examiner first places the vibrating fork behind the patient's ear, and when the patient can no longer hear the tone, the tines of the vibrating fork are placed in front of the external auditory canal of the same ear. A normal result is when the patient can still hear the tone when the fork is placed by the ear canal. If the Rinne test is abnormal on the side where the tone perception lateralized with the Weber test, then the patient likely has a conductive hearing loss ...