To describe the rare process of osteolytic labyrinthitis, previously referred to as labyrinthine sequestrum, which involves progressive obliteration of the bony and membranous labyrinth with eventual ...supplantation with soft tissue and, in some cases, bony sequestrum.
Three patients with diverse presentations of osteolytic labyrinthitis from two tertiary care academic medical centers.
Case series report analyzing the relevant clinical, radiologic, pathologic, and surgical data on our patients with osteolytic labyrinthitis and comparing these index cases to the existing literature.
We describe the varying image findings seen in osteolytic labyrinthitis on computed tomography and magnetic resonance imaging. Also, we report successful surgical intervention and hearing rehabilitation with cochlear implantation in patients with osteolytic labyrinthitis.
Our three patients presented with profound sudden sensorineural hearing loss and vertigo consistent with labyrinthitis. None of the three patients had a history of chronic otitis media. Imaging workup revealed varying degrees of erosion to the otic capsule bone demonstrating the spectrum of disease seen in osteolytic labyrinthitis. Although two cases showed osteolytic changes to the semicircular canals and vestibule, the first case revealed frank bony sequestrum within the obliterated labyrinth. The three cases were taken for surgical debridement and cochlear implantation.
We propose the new term, osteolytic labyrinthitis-previously referred to as labyrinthine sequestrum-to describe the rare spectrum of disease characterized by destruction of the osseous and membranous labyrinth and potential supplantation with bony sequestrum. Cochlear implantation is a viable option in selected patients with osteolytic labyrinthitis.
Labyrinthitis ossificans (LO) may occur following meningitis and, in cases where cochlear implantation is indicated, complicate electrode insertion. LO is critical to identify for successful cochlear ...implantation, and histopathology is more sensitive than imaging for identification of LO. Herein we utilize otopathologic techniques to study the timing and location of intracochlear tissue formation following meningitic labyrinthitis (ML).
Retrospective review.
Academic institution.
Temporal bone specimens with a history of bacterial ML were histologically evaluated. The location and extent of intracochlear tissue formation within the scala tympani (ST) and scala vestibuli (SV) were graded, and spiral ganglion neurons were counted.
Fifty-one temporal bones were identified: 32 with no intracochlear tissue formation, 9 with fibrosis alone, and 10 with LO. Fibrosis was identified as early as 1.5 weeks after ML, while ossification was found only in specimens that survived multiple years after ML. All LO cases showed ossification of the ST at the round window membrane (RWM) with continuous extension throughout the basal turn. Extent of SV ossification correlated with that in the ST but showed frequent isolated distal involvement of the cochlea. Spiral ganglion neuron counts were lower than those in age-matched controls.
In this human temporal bone study, we found that postmeningitic LO results in ossification at the RWM with continuous extension into the ST of the basal turn and variable involvement of the SV. Identification of a patent basal turn beyond RWM ossification of the ST should permit full electrode insertion.
Retrospective review.
Conclusion The patients with serous labyrinthitis caused by acute otitis media (AOM) exhibited various patterns of nystagmus in which direction-fixed irritative-type nystagmus was the most common ...pattern. Differential effects on inner ear function by toxic or inflammatory mediators may be responsible for the various manifestation of nystagmus. Objective This study aimed to investigate nystagmus patterns in patients with serous labyrinthitis, and discuss possible mechanisms. Methods From October 2011 to March 2014, 13 consecutive patients with serous labyrinthitis were included. Eye movements of the patients were serially examined using video-nystagmography, and patterns of nystagmus were investigated. Results The most commonly observed pattern was direction-fixed nystagmus (nine of 13 patients). Of these, eight showed irritative-type, and one showed paretic-type. Direction of nystagmus, although the intensity gradually decreased, was not changed during the course of treatment. One patient showed direction-changing spontaneous nystagmus, which changed into paretic-type direction-fixed nystagmus 1 day after myringotomy. Three patients exhibited persistent direction-changing positional nystagmus in a supine head-roll test. Of them, two showed apogeotropic and one showed geotropic type. In all 13 patients, vertigo and hearing loss were improved after the treatment.
Labyrinthitis most commonly results from an infectious and less commonly from an inflammatory process of the inner ear, but it can be associated with temporal bone trauma, hemorrhage, or tumor. This ...inflammation (regardless of the etiology) disrupts the transmission of sensory information from the ear to the brain. Labyrinthitis ossificans is the pathological ossification of the membranous labyrinthine spaces in response to an insult to the inner ear involving membranous labyrinth or the endosteum of the otic capsule. Herein, we present a case of a 67-year-old female with progressive bilateral sensorineural hearing loss and positional vertigo.
To demonstrate characteristic nystagmus findings in acute otitis media (AOM) complicated by serous labyrinthitis and discuss the mechanism of direction-changing positional nystagmus (DCPN) in this ...condition.
A patient with AOM complicated by serous labyrinthitis on the left side.
Video nystagmography and 3D fluid attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI).
Characterize positional nystagmus in a head-roll test observing the change of nystagmus direction in process of time and compare findings of temporal bone 3D FLAIR MRI.
A previously healthy 50-year-old man who complained of acute otalgia, hearing loss, and vertigo was diagnosed with AOM complicated by serous labyrinthitis on the left side. A head-roll test performed on the day when vertigo developed showed persistent geotropic DCPN. While pre- and postcontrast T1-weighted MRI showed no signal abnormality in both inner ears, 10-minute delay postcontrast 3D FLAIR image showed enhancement in the inner ear on the left side. Four-hour-delay postcontrast 3D FLAIR images showed more conspicuous enhancement of the whole cochlea, vestibule, and semicircular canals on the left side.
In AOM complicated by serous labyrinthitis, density of perilymph may increase due to direct penetration of cytokines and other inflammatory mediators from the middle ear into perilymph and breakdown of blood-labyrinth barrier that causes vascular leakage of serum albumin into perilymph. The density difference between perilymph and endolymph makes the semicircular canal gravity sensitive. A buoyant force is also generated by gravity, causing indentation of endolymphatic membrane in the ampulla and cupula displacement. Thus, at the early stage of serous labyrinthitis, a head-roll test may elicit persistent geotropic DCPN, of which the direction can be changed over time.
Hearing impairment can be the cause of serious socio-economic disadvantages. Recent studies have shown inflammatory responses in the inner ear co-occur with various damaging conditions including ...noise-induced hearing loss. We reported pro-inflammatory cytokine interleukin-6 (IL-6) was induced in the cochlea 6
h after noise exposure, but the pathophysiological implications of this are still obscure. To address this issue, we investigated the effects of IL-6 inhibition using the anti-IL-6 receptor antibody (MR16-1).
Noise-exposed mice were treated with MR16-1 and evaluated. Improved hearing at 4
kHz as measured by auditory brainstem response (ABR) was noted in noise-exposed mice treated with MR16-1. Histological analysis revealed the decrease in spiral ganglion neurons was ameliorated in the MR16-1-treated group, while no significant change was observed in the organ of Corti. Immunohistochemistry for Iba1 and CD45 demonstrated a remarkable reduction of activated cochlear macrophages in spiral ganglions compared to the control group when treated with MR16-1.
Thus, MR16-1 had protective effects both functionally and pathologically for the noise-damaged cochlea primarily due to suppression of neuronal loss and presumably through alleviation of inflammatory responses. Anti-inflammatory cytokine therapy including IL-6 blockade would be a feasible novel therapeutic strategy for acute sensory neural hearing loss.
Human otopathology following drill-out procedures for cochlear implantation (CI) in cases with labyrinthitis ossificans (LO) has not been previously described. This study uses the high sensitivity of ...histopathology to (1) evaluate surgical drill-out technique with associated intracochlear findings and (2) quantify spiral ganglion neuron populations in a series of patients with LO who underwent CI.
Retrospective otopathology study.
Otopathology laboratory.
Temporal bone (TB) specimens from cases with evidence of preoperative intracochlear fibroossification that required a drill-out procedure for CI electrode array insertion were included. All cases were histopathologically evaluated and 3-dimensional reconstructions of the cochleae were performed to interpret drilling paths and electrode trajectories.
Five TB specimens were identified, of which 4 underwent drill-out of the basal turn of the cochlea and 1 underwent a radical cochlear drill-out. In multiple TBs, drilling was imprecise with resultant damage to essential structures. Two TBs showed injury to the modiolus, which was associated with substantially decreased or even absent neuronal populations within these areas. In addition, 2 cases with inadequate drill-out or extensive LO of the basal turn resulted in extracochlear placement of electrode arrays into the vestibule due to persistent obstruction within the basal turn.
Otopathology highlights the challenges of drill-out procedures in cases of LO. Imprecise drilling paths, due to distortion of normal cochlear anatomy, risk injury to the modiolus and adjacent neurons as well as extracochlear placement of electrode arrays, both of which may contribute to poorer hearing outcomes.
Acute spontaneous vertigo with idiopathic sudden sensorineural hearing loss (ISSNHL) can be diagnosed as labyrinthitis, which has a poorer prognosis than ISSNHL without vertigo. Thus, we aimed to ...identify the effect of the baseline vestibular function on the prognosis of labyrinthitis.
A total of 23 patients with labyrinthitis was retrospectively divided into the recovered group (complete recovery, partial recovery) and the nonrecovered group (slight improvement, no improvement). Differences in caloric weakness and gain in the video head impulse test (vHIT) between the two groups were compared. In addition, the prognostic value of the vHIT on each of the three semicircular canals in predicting hearing recovery was analyzed using a linear regression model.
In final pure-tone audiometry, 2 patients (8.70%) exhibited complete recovery, 4 patients (17.39%) had partial recovery, and 17 patients (73.91%) had slight or no improvement. The initial ipsilesional posterior canal (iPC) gain and the contralesional anterior canal (cAC) gain were significantly decreased in the nonrecovered group (p < 0.013 for iPC and p < 0.007 for cAC, Mann-Whitney U test). The mean hearing gain was positively correlated with the iPC gain (R2 = 0.36, p = 0.003, Spearman correlation analysis).
An abnormal iPC gain may be a poor prognostic factor for hearing recovery. Additionally, the vHIT on the three semicircular canals can provide prognosis and insights into the pathophysiological mechanisms in patients with labyrinthitis.