Bilateral vestibulopathy gas pain in shoulder

A physician can make the diagnosis based on history, findings on physical examination, and the results of vestibular tests (ENG and rotatory chair) . One should suspect bilateral loss when there is a combination of unsteadiness and decreased vision when the head is rotating (i.e. oscillopsia).

According to Janky et al (2018), in children "A referral for vestibular evaluation should be considered for children whose hearing loss is greater than 66 dB and particularly those who sit later than 7.25 months or walk later than 14.5 months or whose parents report concerns for gross motor development". So if we understand this correctly, if a child needs a cochlear implant and who was late to sit or walk, bilateral vestibular loss should be suspect. The number of children with bilateral loss is presumably far less than adults, as they are due to very rare conditions. Bedside testing

On physical examination, the tandem Romberg test, the dynamic visual acuity test, and the ophthalmoscope tests are the three most helpful confirmatory tests. The ophthalmoscope test is particularly important as it is straightforward to perform and the results are not greatly affected by cooperation or lack of it. The horizontal head impulse test is favored by some authors (e.g. Weber et al, 2009)

The cervico-ocular reflex is easy to check with a swivel chair and video-frenzel goggles, but it is variably increased. It is inconsistent and not a reliable sign (Schubert et al, 2004). We only do this test in severe bilaterals, and are not sure of its sensitivity ourselves.

The Rotatory chair test is the "gold standard" test and is superior to Caloric testing, VHIT testing, and VEMP testing. It is also the hardest to access, but it is generally available in large metropolitan areas. For example, in Chicago, it is done at Chicago Dizziness and Hearing, which is affilliated with Northwestern University, but is not done at the other 4 universities with medical schools in Chicago.

Note that the rotatory chair test is generally needed to categorize bilateral patients. Caloric testing by itself is not sufficient, as because of the high variability of caloric tests, even absent caloric responses are sometimes encountered in otherwise normal individuals (Furman and Kamerer, 1989). Although recent authors suggest that a limit of 27 deg/sec. is sufficient (Zapala et al, 2008), in our opinion, this limit is not generally applicable because of the wide variation in how testing is performed, and because of the intrinsic variability of ENG responses.

The rotatory chair test assesses both high and low frequencies. It is the only "full spectrum" vestibular test — the alternatives just cover a portion of the bandwidth of the vestibular system (see below). This is why the rotatory chair test is the "gold standard".

Visual suppression is the process of attempting to keep the eyes on a target moving with the person, while their head is being rotated. Visual suppression testing can be useful in detecting patients who are pretending to have gentamicin ototoxicity in a hope of being compensated. The idea here is that bilateral patients have a much easier time than normal patients doing suppression, as they have nothing to suppress. Patients who are pretending to have bilateral loss, sometimes are unable to stop their eyes from jumping while suppressing and rotating. We think the best way to do this is with the rotatory chair.

Caloric testing is much easier to access than rotatory chair testing, being available almost universally, but it is also prone to false positives. While the rotatory chair assesses all frequencies, both high and low, the caloric test only assesses low frequencies (roughly 0.003 Hz). The caloric test is more sensitive than the VHIT test, but it takes more time. It has quite a bit of variabilty as well, which limits its usefulness. The average caloric response is about 100, and thus the criterion of 20 means that someone must lose about 80% of their low frequency response.

The "VHIT" test, can be used to detect bilateral loss. As of 2018, this is quick and fairly effective, and it has supplanted the VAT test (see below). The VHIT test ONLY tests high frequencies, roughly 3 hz, and can miss a low-frequency pattern vestibulopathy. Its main advantage over the rotatory chair is that it is a less expensive device for clinicians, and also because it is very quick. The VHIT can be used to detect worsening in vestibular function, but it does not provide as clear a paramater regarding total vestibular function as the rotatory chair, gain-TC product (Hain, Cherchi and Perez, 2018).

VEMP testing is nearly always reduced in bilateral vestibular loss due to aminoglycoside ototoxicity, and the combination of absent VEMP’s and absent calorics is probably nearly as good as rotatory chair testing for diagnosis of bilateral vestibular loss, given that technique is good. VEMPs are also reduced in older persons, and their utility diminishes after the age of 60. There are two types of VEMPS: cVEMPs and oVEMPS. cVEMPs are often preserved in patients with bilateral vestibular neuritis. oVEMPS are usually gone. The reason for this is presumably that vestibular neuritis generally affects the superior vestibular nerve.

neuropathy. OAE’s should be impaired in persons with aminoglycoside toxicity. VEMP testing is useful in detecting otolith function. When patients have both cVEMPs and rotatory chair loss, a process that affects the entire ear is likely. When cVEMPs are spared, this usually means only the superior division of the ear is affected.

been exposure (a tick bite in an endemic area). These tests are all very low yield. Although one might think that Lyme would be associated with bilateral loss, as it is another spirochete such as syphilis, as of 2016, there was only a single report (of a single patient).

for months even after gentamicin is stopped. When using rotatory chair testing to attempt to establish long term prognosis, another test at about 2 years or later is recommended as recent data suggests that partially injured hair cells may recover in the interim. These comments are not absolute and there are occasional exceptions where people are seen who do better or worse than would be expected from their rotatory chair tests.

3-6 months, appliances are rarely needed to get about by one year. The exception to this general rule are patients with severe loss, who also have other medical problems such as neuropathy or brain damage. After 2 years, many patients also have substantial improvement in their rotatory chair tests compared to those done at 3 months, attributed to a combination of adaptation (substitution), plasticity, and recovery of hair cells that were damaged but not killed.

falls. Symptoms are generally the worst in the first 6 months and get better from then on out. You will not be likely to need to use a wheelchair for your bilateral vestibular loss, or even a walker after two years, unless there is something wrong with you other than bilateral vestibular loss.

• Fujimoto C, Murofushi T, Chihara Y, Ushio M, Suzuki M, Yamaguchi T, Yamasoba T, Iwasaki. Effect of severity of vestibular dysfunction on postural instability in idiopathic bilateral vestibulopathy. S.Acta Otolaryngol. 2013 May;133(5):454-61. doi: 10.3109/00016489.2012.742565. Epub 2013 Jan 28.