Tinnitus in Normal-Hearing Participants after Exposure to Intense Low-Frequency Sound and in Ménière’s Disease Patients

Abstract

Tinnitus is one of the three classical symptoms of Ménière’s disease (MD), an inner ear disease that is often accompanied by endolymphatic hydrops. Previous studies indicate that tinnitus in MD patients is dominated by low frequencies, whereas tinnitus in non-hydropic pathologies is typically higher in frequency. Tinnitus of rather low-frequency (LF) quality was also reported to occur for about 90 s in normal-hearing participants after presentation of intense, LF sound (120 dB SPL, 30 Hz, 90 s). LF sound has been demonstrated to also cause temporary endolymphatic hydrops in animal models. Here, we quantify tinnitus in two study groups with chronic (MD patients) and presumably transient endolymphatic hydrops (normal-hearing participants after LF exposure) with a psychophysical procedure. Participants matched their tinnitus either with a pure tone of adjustable frequency and level or with a noise of adjustable spectral shape and level. Sensation levels of matching stimuli were lower for MD patients (mean: 8 dB SL) than for normal-hearing participants (mean: 15 dB SL). Transient tinnitus after LF-exposure occurred in all normal-hearing participants (N = 28). About half of the normal-hearing participants matched noise to their tinnitus, the other half chose a pure tone with frequencies below 2 kHz. MD patients matched their tinnitus with either high-frequency pure tones, mainly above 3 kHz, or with a noise. Despite a significant proportion of MD patients matching low-pass (roaring) noises to their tinnitus, the range of matched stimuli was more heterogeneous than previous data suggested. We propose that in those participants with noise-like tinnitus, the percept is probably generated by increased spontaneous activity of auditory nerve fibers with a broad range of characteristic frequencies, due to an impaired ion balance in the cochlea. For tonal tinnitus, additional mechanisms are conceivable: focal hair cell loss can result in decreased auditory nerve firing and a central auditory overcompensation. Also, normal-hearing participants after LF-exposure experience alterations in spontaneous otoacoustic emissions, which may contribute to a transient tonal tinnitus.

Burden of rare variants in synaptic genes in patients with severe tinnitus: An exome based extreme phenotype study

“…Meniere disease (MD) is a rare inner ear disorder with a significant genetic contribution [4] , characterized by episodes of vertigo, tinnitus and sensorineural hearing loss [5] . Although vertigo attacks are considered as the main symptom in the first years of the disease, persistent tinnitus is described as the most troublesome symptom by many MD patients [ 6 , 7 ].…”

Rare Deletions or Large Duplications Contribute to Genetic Variation in Patients with Severe Tinnitus and Meniere Disease

“…Interestingly, 80% of individuals with severe tinnitus also suffer from hyperacusis [39], but the molecular links between severe tinnitus and hyperacusis have not been established. While vertigo attacks are noted as the primary symptom during the initial years in individuals suffering from MD, severe tinnitus is reported as the most troublesome symptom by many patients when episodes of vertigo are scarce over time [40,41].…”

Recent Updates of Clinical Guidelines in Diagnosis of Meniere’s Disease: Review Article

“…Hearing may improve between episodes, but as the disease progresses, permanent losses are apparent leading to inverted V audiogram. Almost 50% patients totally lose their hearing in the affected ear fourteen years following their diagnosis (8) . According to the severity of hearing loss between attacks, there are four stages of hearing loss in MD (500 HZ-4 KHZ average): stage one ≤ 25 dB HL), stage two (26-40 dB HL), stage three (41-70 dB HL), and stage four (>71 dB HL) (9) .…”

“…Tinnitus worsens over time and becomes chronic, even when there are no attacks, with the progression of the disease. It described as "roaring" or "ringing" and corresponds to hearing loss (8) .…”