gathering of information, and (c) face-to-face interview at the time of the physical examination. The advantage of a structured questionnaire is its capability to supply comprehensive data regarding the nature of the dizziness/imbalance episodes, accompanying symptoms, additional medical conditions, medications, and lifestyle. However, such questionnaires must be simplified so that it is understandable for the patient and well organized for the practitioner to efficiently interpret the data. Moreover, these questionnaires should be completed prior to the appointment rather than hurriedly filled out in the waiting room. A well constructed and thoughtfully completed questionnaire can be a valuable tool for the examiner to review prior to the patient interview. Alternatively, a medical assistant can conduct a phone interview and record the data. The disadvantages of this approach include that this method can be more time consuming and costly, and the resulting data are less comprehensive than the data from a written questionnaire. Finally, the face-to-face interview by the physician is the most important step in confirming and/or clarifying what the patient has either written in the questionnaire or told the medical assistant by phone. Using the written questionnaire as a guide allows the examiner to ask directed questions during the interview in an efficient fashion to best understand the patient’s symptom complex (Table 165.1).
TABLE 165.1 THE HISTORY OF PRESENT ILLNESS IN A PATIENT WITH DIZZINESS
diving, hyperbaric oxygen treatments, straining (e.g., weight lifting or childbirth), or changes in altitude (e.g., airplane flights or driving in the mountains), especially during an upper respiratory infection that causes congestion. Posttraumatic vertigo may be due to perilymphatic fistula(s) (PLF) of the oval and/or round windows (8, 9, 10, 11), delayed endolymphatic hydrops (12), BPPV (13), migraine, or middle ear surgery (14). Furthermore, trauma may cause a dehiscence of the superior SCC if the bone covering the canal was thin prior to the injury (15, 16, 17).
30S ribosomal subunit and cause mRNA to be misread. While the use of systemic aminoglycosides is declining in developed nations due to their significant toxicities and the availability of better alternatives, aminoglycosides are still widely used in developing countries. This is because aminoglycosides are inexpensive and effective against diseases such as multidrug-resistant tuberculosis (20, 21).
TABLE 165.2 MEDICATIONS THAT MAY CAUSE DIZZINESS
and Norco) abuse has been reported to cause permanent, rapidly progressive, sensorineural hearing loss (35, 36, 37, 38). Although less common than auditory symptoms, vestibular symptoms (e.g., vertigo or disequilibrium) caused by high-dose analgesics can occur. When vestibular symptoms do develop, their onset can even precede tinnitus (Table 165.2) (39).
TABLE 165.3 THE NEUROTOLOGIC EXAMINATION OF THE DIZZY PATIENT
associated with SCC dehiscence or PLF. Finally, the 3-inch foam pad is used to alter sensory input to the proprioceptive system during quiet stance with eyes closed to emphasize the use of vestibular cues for balance.
Figure 165.2 Tools necessary for a neurotologic examination of the dizzy patient. A: Tools include (1) tuning forks: 512 Hz for standard auditory stimulus (Weber and Rinne testing), 128 Hz to assess vibrotactile sensation in the lower extremities, and 256 Hz (not shown) for the malleolar test for third-window pathology, (2) a pneumatic otoscope including a Siegel pneumatic speculum to assess tympanic membrane mobility and to assess third-window pathology, (3) Frenzel lenses, and (4) a 3” foam pad for the foam Romberg test. B: Frenzel lenses provide magnification of the eyes and remove visual fixation. Peripheral vestibular nystagmus is enhanced and central nystagmus is suppressed when visual fixation is removed using Frenzel lenses.
fast-phase movement toward the healthy ear (away from the damaged side). Removing visual fixation (e.g., placing Frenzel lenses on a patient) or gazing in the direction of the fast phase enhances the nystagmus, while gazing in the direction of the slow phase suppresses the nystagmus. This effect is called Alexander law. Alexander classified nystagmus as first-, second-, and third-degree nystagmus. Firstdegree nystagmus is the least intense and is only observed with gaze toward the fast phase. Second-degree nystagmus is more intense and is observed with the eyes in primary gaze position or when gazing toward the fast phase. Thirddegree nystagmus is the most intense and is present when the eyes are in primary gaze position, gazing toward the fast phase or, gazing in the direction of the slow phase. If second- and third-degree nystagmus are present, the finding represents an acute condition or a greater disparity between the good and bad sides. Characterizing the vestibular nystagmus degree is important in determining the time course and degree of compensation for a peripheral vestibular lesion. For example, immediately after unilateral peripheral vestibular damage (e.g., vestibular ablative surgery or vestibular neuronitis), third-degree nystagmus is observed. Over the next several days, the nystagmus intensity declines passing through the stages of second- and then first-degree nystagmus. It has been postulated that the neural integrator, which is responsible for gaze-holding, is disabled when the nervous system is presented with a sudden sustained asymmetric vestibular input. The nystagmus intensity declines as the central system compensates (for a thorough description, see Ref. (40)).