Contribution of Otoacoustic Emissions for Diagnosis of Atypical or Recurrent Intracranial Hypotension. A Cases Series.

BACKGROUND: The diagnosis of spontaneous or post-traumatic intracranial hypotension mainly rely on clinical features and neuroimaging. In atypical presentations, other non-invasive tests are missing to support the diagnosis of intracranial hypotension. The assessment of otoacoustic emissions (OAE) shown interest to monitor intracranial pressure mainly in cases of intracranial hypertension. This non-invasive method was also assessed in response to pressure change after lumbar puncture. A few reports showed abnormal results of distortion product otoacoustic emissions (DPOAE) in cases of spontaneous or post-traumatic intracranial hypotension. We describe additional results in a series of intracranial hypotension cases. We discuss the interest of DPOAE assessment in atypical presentations of intracranial hypotension. We review the other non-invasive tests reported in literature. METHODS: We studied 4 atypical or recurrent cases of spontaneous or post-traumatic intracranial hypotension by recording OAE in sitting then supine position. RESULTS: Unilateral or bilateral abnormal changes of DPOAE were recorded in all cases, in response to postural test. These changes were present even in the absence of vestibular symptoms. CONCLUSION: The study of OAE may be a non-invasive tool for the diagnosis of spontaneous intracranial hypotension.

[Hearing disorders in 3- to 12-year-olds]. / L'audition de l'enfant de 3 à 12 ans.

The hearing disorders of the child between 3 and 12 years are dominated by the conductive hearing loss. The questioning, looking for risk factors, as well as the otoscopy are essential to detect and diagnose a hearing disorder. Screening tests help to identify the children with risk of hearing loss. Then, the child is sent for diagnosis towards an ENT specialist or a specialized structure. In spite of the frequency of the conductive hearing loss, in case of the slightest doubt, a sensorineural hearing loss must be always looked for by a puretone audiometry examination via the headphones.

The neurologist and the hydrops.

The presence of endolymphatic hydrops has been studied in many neurological disorders. The pathophysiological mechanisms may involve CSF pressure variations, transmitted to the innear ear. This hydrops could play a role in vestibular or cochlear symptoms. For the ENT specialist, the etiological diagnosis of endolymphatic hydrops is a challenge, and neurological etiologies must be known. The treatment of these neurological causes could be effective on cochleo-vestibular symptoms. The knowledge of endolymphatic hydrops could also be a target for noninvasive tests, able to estimate CSF pressure variations. For the neurologist, this could represent a useful tool for the diagnosis and follow-up, in some of these neurological disorders, related to a CSF pressure imbalance. The purpose of this paper is to summarize literature data on endolymphatic hydrops in neurological disorders. We define some neurological conditions, for which there is a particular interest in noninvasive investigations of endolymphatic hydrops.

Out-of-body experience in vestibular disorders - A prospective study of 210 patients with dizziness.

Out-of-body experiences (OBEs) are states during which people experience their centre of awareness as located outside of their physical body, along with the sensation of seeing the environment from an elevated viewpoint. OBE is encountered in epilepsy, migraine and depersonalization, and it is not an uncommon experience in the general population. Current neuroscientific models of bodily self-consciousness consider that OBE are related to a failure to integrate visual, somatosensory and vestibular signals. These models have highlighted the importance of visual-vestibular mismatch in OBE. Case reports from older clinical literature suggest that vestibular disorders may precipitate OBE, but we were lacking population-based evidence that OBE is related to vestibular disorders. The present observational, prospective study describes otoneurological, neuropsychological and phenomenological correlates of OBE in the largest sample of patients with dizziness to date (n = 210) compared to a group of age- and gender-matched controls with no history of dizziness (n = 210). We show a significantly higher occurrence of OBE in patients with dizziness (14%) than in healthy participants (5%). Most of the patients experienced OBE only after they started having dizziness for the first time. OBE in patients with dizziness were mainly related to peripheral vestibular disorders. We also identify depersonalization-derealization, depression and anxiety as the main predictors of OBE in patients with dizziness, as well as a contribution of migraine. Depersonalization-derealization was the only significant predictor of OBE in healthy controls. Altogether, our data indicate that OBE in patients with dizziness may arise from a combination of perceptual incoherence evoked by the vestibular dysfunction with psychological factors (depersonalization-derealization, depression and anxiety) and neurological factors (migraine).

Diagnosis and Treatment of Perilymphatic Fistula.

Perilymphatic fistula (PLF) is defined as an abnormal communication between the fluid (perilymph)-filled space of the inner ear and the air-filled space of the middle ear and mastoid, or cranial spaces. PLF is located in the round or oval window, fractured bony labyrinth, microfissures, anomalous footplate, and can occur after head trauma or barotrauma, chronic inflammation, or in otic capsule dehiscence. This clinical entity was initially proposed more than a century ago, yet it has remained a topic of controversy for more than 50 years. The difficulty of making a definitive diagnosis of PLF has caused a long-standing debate regarding its prevalence, natural history, management and even its very existence. In this present study, we will discuss the symptoms, physiological tests (focusing on vestibular assessment) and imaging studies. Referring to a previous criticism, we will share our classification of PLF into 4 categories. Furthermore, we will summarize a nationwide survey using a novel and widely used biomarker (Cochlin-tomoprotein [CTP]) for PLF diagnosis in Japan and present the results of the new diagnostic criteria. PLF is surgically correctable by sealing the fistula, and appropriate recognition and treatment of PLF can improve hearing and balance, and in turn, improve the quality of life of afflicted patients. Therefore, PLF is an especially important treatable disease for otologists.

Distorted own-body representations in patients with dizziness and during caloric vestibular stimulation.

There is increasing evidence that vestibular disorders evoke deficits reaching far beyond imbalance, oscillopsia and spatial cognition. Yet, how vestibular disorders affect own-body representations, in particular the perceived body shape and size, has been overlooked. Here, we explored vestibular contributions to own-body representations using two approaches. Study 1 measured the occurrence and severity of distorted own-body representations in 60 patients with dizziness and 60 healthy controls using six items from the Cambridge Depersonalization Scale. 12% of the patients have experienced distorted own-body representations (their hands or feet felt larger or smaller), 37% reported abnormal sense of agency, 35% reported disownership for the body, and 22% reported disembodiment. These proportions were larger in patients than controls. Study 2 aimed at testing whether artificial stimulation of the vestibular apparatus produced comparable distortions of own-body representations in healthy volunteers. We compared the effects of right-warm/left-cold caloric vestibular stimulation (CVS), left-warm/right-cold CVS and sham CVS on internal models of the left and right hands using a pointing task. The perceived length of the dorsum of the hand was increased specifically during left-warm/right-cold CVS, and this effect was found for both hands. Our studies show a vestibular contribution to own-body representations and should help understand the complex symptomatology of patients with dizziness.

Objective tinnitus associated with essential palatal myoclonus: report in a child.

Palatal myoclonus is an uncommon, rhythmic, "shock-like" involuntary movement of the muscles of the soft palate, throat, and other structures derived from the branchial arcs. Objective tinnitus is frequently neglected in review articles about childhood tinnitus. Our aim was to present the case of a 7-year-old girl with bilateral objective tinnitus due to palatal myoclonus without hearing impairment (normal hearing thresholds between 250 Hz and 8 kHz) but with otherwise normal hearing thresholds (250 Hz-8 kHz) and no evidence of intracerebral or systemic disorders. No treatment was useful.

Intralabyrinthine penetrating ventilation tube with preservation of hearing: an unusual clinical situation.

Introduction Traumatic perilymphatic fistula is not a rare event with regards to sport activities or traffic accident. However, iatrogenic damage to the inner ear can occur following the common use of grommets and ventilation tube insertion. Objectives To report an unusual case of insertion of aeration tube into the vestibule trough the stapes footplate. Resumed Report A 62-year-old woman experienced iatrogenic penetration into the vestibule from a ventilation tube inserted for retraction pocket management. The event was misdiagnosed both by the surgeon and by the emergency room physicians, leading to delay in the management. However, preservation of the hearing function lasted for 2 weeks prior to deafness, thanks to the valve of Bast, which preserved the cochlear fluid. Conclusion This case gives us the opportunity to stress the need for systematic clinical examination of traumatic injury to the ear and to recommend performing multiplanar millimetric computed tomography scan with accurate interpretation. Traumatic injuries should be referred to a dedicated traumatic emergency referral center.

Intralabyrinthine Penetrating Ventilation Tube with Preservation of Hearing: An Unusual Clinical Situation

Introduction Traumatic perilymphatic fistula is not a rare event with regards to sport activities or traffic accident. However, iatrogenic damage to the inner ear can occur following the common use of grommets and ventilation tube insertion. Objectives To report an unusual case of insertion of aeration tube into the vestibule trough the stapes footplate. Resumed Report A 62-year-old woman experienced iatrogenic penetration into the vestibule from a ventilation tube inserted for retraction pocket management. The event was misdiagnosed both by the surgeon and by the emergency room physicians, leading to delay in the management. However, preservation of the hearing function lasted for 2 weeks prior to deafness, thanks to the valve of Bast, which preserved the cochlear fluid. Conclusion This case gives us the opportunity to stress the need for systematic clinical examination of traumatic injury to the ear and to recommend performing multiplanar millimetric computed tomography scan with accurate interpretation. Traumatic injuries should be referred to a dedicated traumatic emergency referral center. .