Dizziness is a common complaint, with approximately 35 percent of adults reporting dizziness, with the prevalence increasing dramatically with age (Agrawal, 2009). As the profession of audiology has evolved, so has our understanding of the various disorders that cause imbalance and dizziness. This article will walk you through the case of Sunny Susan (patient’s name changed to protect identity), a woman who I first saw as a balance patient after she had spent over 22 years struggling with recurrent dizziness and progressive hearing loss.
The first time she was seen at the clinic was 12 years prior to her visit with me. She was age 54 years, and was referred by her primary care physician for hearing loss, potentially due to occupational noise exposure. No other symptoms, besides a gradual hearing loss, were noted. At that time, a mild high-frequency hearing loss, with a pattern consistent with noise exposure, was found. Tympanometry and acoustic reflex results were also noted as normal (see FIGURE 1).
She returned to the same clinic six years later, due to dizziness and decreased hearing. At that time, her hearing had dropped in the low and mid frequencies, and a slight air-bone gap was seen at 500, 2000, and 4000 Hz. Tympanometry and acoustic reflex results were normal again. At this time, Sunny Susan was also referred to an otolaryngologist for dizziness, as the clinic did not yet have vestibular testing (see FIGURE 2).
Third Time’s a Charm
She was back again, three years later (nine years since baseline), due to hearing difficulties, bilateral, pulsatile tinnitus, as well as ongoing dizziness. This time, the audiogram revealed a moderate, rising to mild, low-frequency conductive hearing loss with bone-conduction thresholds at -10 dB HL at 500 and 1000 Hz.
Tympanometry revealed that the middle ear pressure was slightly negative (-75 and -100 daPa MEP for the left and right) with present reflexes. The audiologist at that time noted that she experienced dizziness during acoustic reflex threshold testing with stimulation to the right ear and not the left. The patient was then referred to the otolaryngologist to rule out a middle ear disorder (see FIGURE 3).
In the meantime, she had traveled quite a distance to be seen by a larger medical facility, and had received a diagnosis of Ménière’s disease. Twelve years since baseline, she landed on my schedule, as the clinic had added vestibular assessment the year prior. She reported balance problems with a veering to the left side for 10 years, with increased dizziness with bending forward, straining, or blowing her nose. At this visit, the hearing test was the same configuration since the last one, but much worse in the low frequencies, inching toward “severe.” Unfortunately, acoustic reflex thresholds were difficult to interpret due to a poor seal/excess needle deflection (see FIGURE 4).
Fortunately, at this time, I was able to move forward with balance testing, which included modified Clinical Test of Sensory Integration of Balance (mCTSIB) testing, and Video Nystagmography (VNG). As I progressed, however, I already had some thoughts in mind in terms of potential etiology. Was it Ménière’s Disease, as previously diagnosed? I doubted it. Why? Well, first, we must consider the configuration. While the hearing loss presented as a reverse-slope hearing loss, it is conductive, and not sensory neural.
The next thing that caught my attention was the dizziness provoked while bending down. We all learn that benign paroxysmal positional vertigo (BPPV) is the most common cause of dizziness (von Brevern, 2007), so it is important to rule that out. Although other things didn’t align, as follows:
- Conductive hearing loss with normal tympanograms
- Progressive hearing loss
- Dizziness when straining or blowing her nose
At this point, what else could it be?
Perhaps an uncompensated unilateral weakness, due to the veering, with a “poor historian,” and perhaps head-turns were the issue, not the positions? We have all had poor historians in our clinics, and she just wasn’t one of them.
Tests and Results
On to testing! As mentioned earlier, in that clinic, we had VNG and mCTSIB, using dense foam. The results may surprise you… or might not.
- Oculomotors are within normal limits (Good! Not central!).
- Gaze testing is negative for nystagmus in any position, with and without target.
- High-frequency headshake is negative for post-headshake nystagmus.
- Positional testing (moving slowly, as we should for this test!) is negative for nystagmus in any position, with or without fixation.
- Dix-Hallpike is “non-classical abnormal:” patient has dizziness in both head right and head left.
- Nystagmus onset is almost instantaneous (non-classical) but it does slow and resolve over the course of one to two minutes (lasts longer in the right ear).
- The nystagmus itself is a vertical nystagmus in each position, which is typically deemed as a central finding, right?
- Caloric testing reveals a strong, symmetric response.
- No significant unilateral weakness or directional preponderance.
mCTSIB is mildly abnormal, with the patient unable to stand on foam with eyes closed for more than 15 seconds.
Any ideas as to where this is going?
In an informal assessment, recording of the patient’s eyes as she did a valsalva maneuver revealed, again, a vertical nystagmus.
From our wheelhouse of tests, the next test for me was cervical vestibular evoked myogenic potentials (cVEMP). Due to scheduling constraints, my colleague completed this testing. cVEMP testing revealed strong, symmetric responses at 95dBnHL. Testing at 70dBnHL showed a sustained N1-P1 response (see FIGURE 5).
My next recommendation was for a fine-cut computed tomography (CT) scan, and I requested this of the primary care physician, who was the referring physician. When I learned that two weeks post-testing they had not yet ordered the test, and instead had recommended the patient come back to discuss hearing aids, I called and spoke with the nurse. (Note: In this community, the primary physicians often had an overload on their cases, so the nurse was my first line of communication). After having to convince her that no, the patient did NOT have Ménière’s, the CT was finally ordered.
At this point, I enlisted the help of our neighbor otologist, who I had the good fortune of collaborating with across cases. He gladly met with the patient and explained the CT results with her, and steered her to the closest surgeon for the procedure…. Who just happened to be at the large facility that misdiagnosed her. Nonetheless, with the encouragement that she would be back to see me after the surgery, she headed off for surgery.
The surgeon and patient agreed that the right side, which had showed a larger dehiscence and greater symptoms when provoked, would be the first side for surgery.
Unfortunately, surgery does not always go as planned.
While in surgery, almost as soon as the surgeon had reached the dehiscence, the patient, in her words, “started to bleed out, so they packed up and got me out of there as soon as possible.” On the bright side, her symptoms did reduce, probably due to a packed canal (deadened canal). When asked if she would be returning for surgery on the left, the patient said, “I’m feeling better, and just glad for each minute I have on this earth.”
Perspective is everything, isn’t it?
Agrawal Y, Carey JP, Della Santina CC, Schubert MC, Minor LB. (2009) Disorders of balance and vestibular function in US adults: data from the National Health and Nutrition Examination Survey, 2001-2004. Arch Intern Med 169(10):938–944
von Brevern M, Radtke A, Lezius F, et al. (2007) Epidemiology of benign paroxysmal positional vertigo: A population based study. J Neurol Neurosurg Psych 78(7):710–715