Long-Term Follow-up of Hearing Loss in Children and Young Adults With Enlarged Vestibular Aqueducts: Relationship to Radiologic Findings and Pendred Syndrome Diagnosis

OBJECTIVE

To describe the long-term audiologic findings in pediatric patients with enlarged vestibular aqueducts (EVAs). The relationship between the hearing loss (HL) and the dimensions of the EVA, enlarged endolymphatic duct (EED), or enlarged endolymphatic sac (EES) was also investigated. The influence of a Pendred syndrome (PS) diagnosis on the audiologic phenotype was also examined.

STUDY DESIGN

Retrospective analysis of case notes and imaging records, including measurement of the dimensions of the EVA, EED, and EES.

SETTING

Tertiary referral center.

PATIENTS

Twenty-seven patients (21 female, 6 male) had an EVA in at least one ear. Eighty-five percent had bilateral enlargements. Median age at onset of follow-up was 5.0 years, and median follow-up was 9.7 years.

MAIN OUTCOME MEASURES

Hearing thresholds at the start and end of follow-up, rate of progression of HL, history of sudden drops in hearing.

RESULTS

: All ears with an EVA had HL. Average HL at the start and end of follow-up was severe. Thirty-seven percent of patients had progressive HL, and 33% reported sudden drops in hearing. Progression was significantly associated with a history of sudden drops. PS patients had worse hearing at the end of follow-up as compared with nonsyndromic patients. There was no evidence of a relationship between the dimensions of the EVA, EED, or EES and the severity or progression of HL.

CONCLUSIONS

Patients with EVAs should be advised to avoid known trigger factors for sudden drops in hearing (e.g., minor head trauma). A diagnosis of PS may be associated with a worse audiologic prognosis.

Treatment Outcomes and Dose Rate Effects Following Gamma Knife Stereotactic Radiosurgery for Vestibular Schwannomas

BACKGROUND

Gamma Knife radiosurgery (GKRS; Elekta AB) remains a well-established treatment modality for vestibular schwannomas. Despite highly effective tumor control, further research is needed toward optimizing long-term functional outcomes. Whereas dose-rate effects may impact post-treatment toxicities given tissue dose-response relationships, potential effects remain largely unexplored.

OBJECTIVE

To evaluate treatment outcomes and potential dose-rate effects following definitive GKRS for vestibular schwannomas.

METHODS

We retrospectively reviewed 419 patients treated at our institution between 1998 and 2015, characterizing baseline demographics, pretreatment symptoms, and GKRS parameters. The cohort was divided into 2 dose-rate groups based on the median value (2.675 Gy/min). Outcomes included clinical tumor control, radiographic progression-free survival, serviceable hearing preservation, hearing loss, and facial nerve dysfunction (FND). Prognostic factors were assessed using Cox regression.

RESULTS

The study cohort included 227 patients with available follow-up. Following GKRS 2-yr and 4-yr clinical tumor control rates were 98% (95% CI: 95.6%-100%) and 96% (95% CI: 91.4%-99.6%), respectively. Among 177 patients with available radiographic follow-up, 2-yr and 4-yr radiographic progression-free survival rates were 97% (95% CI: 94.0%-100.0%) and 88% (95% CI: 81.2%-95.0%). The serviceable hearing preservation rate was 72.2% among patients with baseline Gardner-Robertson class I/II hearing and post-treatment audiological evaluations. Most patients experienced effective relief from prior headaches (94.7%), tinnitus (83.7%), balance issues (62.7%), FND (90.0%), and trigeminal nerve dysfunction (79.2%), but not hearing loss (1.0%). Whereas GKRS provided effective tumor control independently of dose rate, GKRS patients exposed to lower dose rates experienced significantly better freedom from post-treatment hearing loss and FND (P = .044).

CONCLUSION

Whereas GKRS provides excellent tumor control and effective symptomatic relief for vestibular schwannomas, dose-rate effects may impact post-treatment functional outcomes. Further research remains warranted.

The demonstration of the auditory ossicles by high resolution CT

The high resolution CT scanning system introduced by EMI in 1978 has added a new dimension to computerised tomography in otology. The apparatus used for this study was an EMI CT 5005 body scanner adapted for head and neck scanning and incorporating a high resolution facility. The latter has proved most advantageous in areas of relatively high differential absorption, so that its application to the demonstration of abnormalities in the petrous temporal bone, and in particular middle ear disease, has been very rewarding. Traumatic ossicular disruptions may now be demonstrated and the high contrast of CT often shows them better than conventional hypocycloidal tomography. The stapes is also better visualised and congenital abnormalities of its superstructure have been recorded. These studies have been achieved with a very acceptable level of radiation to the eye, lens and cornea and the technique is clearly a rival to conventional pluridirectional tomography in the assessment of the petrous temporal bone. With further design improvements high resolution CT could completely replace existing techniques.

Mutational analysis of EYA1, SIX1 and SIX5 genes and strategies for management of hearing loss in patients with BOR/BO syndrome

BACKGROUND

Branchio-oto-renal (BOR) or branchio-otic (BO) syndrome is one of the most common forms of autosomal dominant syndromic hearing loss. Mutations in EYA1, SIX1 and SIX5 genes have been associated with BOR syndrome. In this study, clinical and genetic analyses were performed in patients with BOR/BO syndrome focusing on auditory manifestations and rehabilitation.

METHODS

The audiologic manifestations were reviewed in 10 patients with BOR/BO syndrome. The operative findings and hearing outcome were analyzed in patients who underwent middle ear surgeries. The modality and outcome of auditory rehabilitation were evaluated. Genetic analysis was performed for EYA1, SIX1, and SIX5 genes.

RESULTS

All patients presented with mixed hearing loss. Five patients underwent middle ear surgeries without successful hearing gain. Cochlear implantation performed in two patients resulted in significant hearing improvement. Genetic analysis revealed four novel EYA1 mutations and a large deletion encompassing the EYA1 gene.

CONCLUSIONS

Auditory rehabilitation in BOR/BO syndrome should be individually tailored keeping in mind the high failure rate after middle ear surgeries. Successful outcome can be expected with cochlear implantations in patients with BOR/BO syndrome who cannot benefit from hearing aids. The novel EYA1 mutations may add to the genotypic and phenotypic spectrum of BOR syndrome in the East Asian population.

Auditory and vestibular system findings in patients with vascular loops in the internal auditory canal

Many anatomic studies have shown that a loop of the anterior inferior cerebellar artery is frequently found in the cerebellopontine angle and internal auditory canal. The concept of vascular cross-compression has been extended to the eighth cranial nerve, and patients with symptoms of hearing loss, tinnitus, and vertigo have been treated surgically by separating the vascular loop from the nerve. Previous reports have emphasized vascular anatomy, surgical approaches, and treatment results. Our study provides details of audiometric and vestibular system test results in a series of ten patients with prominent vascular loops in the internal auditory canal diagnosed by computerized tomography after subarachnoid space air injection (pneumo-CT). All patients had a unilateral (or asymmetric) hearing loss on the side of the lesion, and no vascular loops were detected on the contralateral sides. Hearing losses ranged from mild to profound. Audiometric findings were generally of a cochlear type, and most patients had excellent speech discrimination. Spontaneous nystagmus was detected in all patients during neurotologic testing, and half of the patients had normal caloric test results. The variability of audiometric and vestibular system test results is probably a reflection of anatomic variations of the vascular loop and its branches. Auditory and vestibular symptoms may be due to a complex interaction between the eighth cranial nerve and the vascular loop, in which the loop compresses the nerve and the nerve compromises circulation to the inner ear. Although symptoms from vascular loops and eighth nerve tumors are similar, the findings of a cochlear type of hearing loss, excellent speech discrimination, and normal caloric test results should raise the suspicion of a vascular loop.(ABSTRACT TRUNCATED AT 250 WORDS)

Audibility and speech perception of children using wide dynamic range compression hearing AIDS

PURPOSE

This study examined the relation of audibility for frequency-specific sounds and the Speech Intelligibility Index (SII) to speech perception abilities of children with sensorineural hearing loss using digital signal-processing hearing aids with wide dynamic range compression.

METHOD

Twenty-six children age 5-15 years with pure-tone averages (0.5, 1.0, and 2.0 kHz) from 60-98 dB HL participated. Three subgroups were created based on the compression characteristics of each hearing aid. Minimum audibility was determined using aided thresholds for frequency-modulated tones and the SII calculated at 55 and 70 dB SPL using the simulated real-ear output of the hearing aid. The Lexical Neighborhood Test (LNT; K. I. Kirk, D. B. Pisoni, & M. J. Osberger, 1995) was presented at 50 and 70 dB SPL.

RESULTS

LNT scores at 70 dB SPL were significantly higher than at 50 dB SPL. Average aided thresholds at 0.5, 1.0, and 2.0 kHz were negatively correlated with LNT scores at 50 dB SPL, and SIIs at 55 and 70 dB SPL were positively correlated with LNT scores at 50 and 70 dB SPL.

CONCLUSIONS

Results support using aided thresholds and speech test scores at soft to loud levels as part of the amplification fitting process.

GGPS1 Mutations Cause Muscular Dystrophy/Hearing Loss/Ovarian Insufficiency Syndrome

OBJECTIVE

A hitherto undescribed phenotype of early onset muscular dystrophy associated with sensorineural hearing loss and primary ovarian insufficiency was initially identified in 2 siblings and in subsequent patients with a similar constellation of findings. The goal of this study was to understand the genetic and molecular etiology of this condition.

METHODS

We applied whole exome sequencing (WES) superimposed on shared haplotype regions to identify the initial biallelic variants in GGPS1 followed by GGPS1 Sanger sequencing or WES in 5 additional families with the same phenotype. Molecular modeling, biochemical analysis, laser membrane injury assay, and the generation of a Y259C knock-in mouse were done.

RESULTS

A total of 11 patients in 6 families carrying 5 different biallelic pathogenic variants in specific domains of GGPS1 were identified. GGPS1 encodes geranylgeranyl diphosphate synthase in the mevalonate/isoprenoid pathway, which catalyzes the synthesis of geranylgeranyl pyrophosphate, the lipid precursor of geranylgeranylated proteins including small guanosine triphosphatases. In addition to proximal weakness, all but one patient presented with congenital sensorineural hearing loss, and all postpubertal females had primary ovarian insufficiency. Muscle histology was dystrophic, with ultrastructural evidence of autophagic material and large mitochondria in the most severe cases. There was delayed membrane healing after laser injury in patient-derived myogenic cells, and a knock-in mouse of one of the mutations (Y259C) resulted in prenatal lethality.

INTERPRETATION

The identification of specific GGPS1 mutations defines the cause of a unique form of muscular dystrophy with hearing loss and ovarian insufficiency and points to a novel pathway for this clinical constellation. ANN NEUROL 2020;88:332-347.

Computed tomography: how accurate a predictor for cochlear implantation?

Cochlear implantation is an accepted medical treatment for profound bilateral postlinguistically acquired hearing loss. Because cochlear implants are still in the process of development, a detailed evaluation of the results of implantation is essential. However, the capability of predetermining the auditory benefit of a cochlear implant is limited and depends upon a number of factors. This report focuses upon the ability of computed tomography (CT) to predict surgical success and audiological results of multichannel cochlear implantation. It also addresses how the disease state might affect the functional benefit of the implant. After undergoing routine clinical and audiological evaluations, 28 cochlear implant candidates underwent CT scans in order to evaluate cochlear patency prior to surgery. Subsequently, 24 patients were implanted with either a single-or 22-channel device. Surgical findings were noted and postoperative audiological assessments of sound detection and speech discrimination were made. The CT risk factors that diminish the likelihood of a successful cochlear implant result are discussed based upon a retrospective comparison of preoperative CT results, surgical findings, and postsurgical audiological evaluations of the 14 patients who received a 22-channel implant. Analysis of the predictive capability of CT will allow clinicians to use that procedure more effectively in the presurgical assessment of cochlear implant candidates.

The role of post-operative imaging in cochlear implant surgery: a review of 220 adult cases

OBJECTIVES

To determine the incidence of abnormal radiological findings after cochlear implantation and their effect on clinical outcomes.

METHODS

Retrospective review of 220 adult cochlear implants. Clinical records and post-operative plain X-rays were reviewed and compared with pre-operative and 6-month post-operative City University of New York (CUNY) speech scores.

RESULTS

There were no cases of extra-cochlear array misplacement. Imaging showed 20 cases of incomplete array insertion (9.2%), 3 cases of kinking of the array (1.4%), 2 cases of tip rollover (0.9%), and 1 case of apparent array fracture (0.5%). Patient management was not altered by abnormal imaging. Patients with abnormal radiological findings had slightly minor improvements (median 39 vs. 56%) in City University of New York (CUNY) speech discrimination scores at 6 months (Mann-Whitney U test, P = 0.043).

CONCLUSION

All abnormalities on post-operative imaging were minor and did not alter patient management. The future role of post-operative imaging is discussed.

Long-term follow-up results of stereotactic radiosurgery for vestibular schwannomas larger than 8 cc

BACKGROUND

Accumulated stereotactic radiosurgery (SRS) experience for large vestibular schwannomas (VSs) based on over 5 years of follow-up are as yet insufficient, and chronological volume changes have not been documented.

METHOD

Among 402 patients treated between 1990 and 2015, tumor volumes exceeded 8 cc in 30 patients. We studied 19 patients with follow-up for more than 36 post-SRS months or until an event. Median tumor volume was 11.5 cc (range; 8.0 to 30.6). The target volume was basically covered with 12.0 Gy.

RESULTS

The median magnetic resonance imaging and clinical follow-up periods were both 98 months (range 49 to 204). Tumor shrinkage was documented in 13 patients (72%), no change in 2 (11%), and growth in the other 3 (17%). Therefore, the crude growth control rate was 83%. All three patients with tumor enlargement needed salvage treatment. Thus, the crude clinical control rate was 84%. Actuarial further procedure-free rates were 91%, 83% and 76%, at the 60th, 120th, and 180th post-SRS month. Among six patients followed chronologically, transient tumor expansion was observed in three (43%) and two cystic VSs showed rapid tumor growth. Transient trigeminal neuropathy occurred in two patients (11%). No patients experienced facial nerve palsy. None of the six patients with useful hearing pre-SRS maintained serviceable hearing. Ventricular-peritoneal shunt placement was required in three patients.

CONCLUSIONS

Long-term tumor control with SRS was moderately acceptable in large VSs. In terms of functional outcome, trigeminal neuropathies and facial palsies were rare. However, hearing preservation remains a challenge. In the long term, chronological tumor volumes were generally decreased after SRS. However, caution is required regarding rapid increases in tumor size, especially for cystic type VSs. Further studies are needed to optimize clinical positioning of SRS for large VSs.

Bionic ear imaging

PURPOSE

The aim of this study was to illustrate the different imaging features of middle and inner ear implants, brainstem implants and inferior colliculus implants.

MATERIALS AND METHODS

We retrospectively reviewed the computed tomography (CT) images of 468 patients with congenital or acquired transmissive or neurosensory hearing loss who underwent surgery. The implants examined were: 22 Vibrant Soundbridge implants, 5 at the long limb of the incus and 17 at the round window, 350 cochlear implants, 95 brainstem implants and 1 implant at the inferior colliculus. All patients underwent a postoperative CT scan (single or multislice scanner) and/or a Dentomaxillofacial cone-beam CT scan (CBCT) (axial and multiplanar reconstruction), and/or a plain-film radiography to visualise the correct position of the implant.

RESULTS

The CBCT scan depicts Vibrant site of implant better than plain-film radiography, with a lower radiation dose compared to CT. For cochlear implants, a single plain radiograph in the Stenvers projection can directly visualise the electrodes in the cochlea. All patients with brainstem or inferior colliculus implants underwent postoperative CT to exclude complications and the assess correct implantation, but the follow-up of these implants can be performed by plain radiography alone.

CONCLUSIONS

CT and CBCT scans are reliable and relatively fast methods for precisely determining the location of middle ear implants. CBCT is preferable to CT because of the lower radiation dose administered; a single plain-film radiograph is enough to visualise and follow-up cochlear, brainstem and inferior colliculus implants.

A case of tinnitus and hearing loss after cerebellar hemorrhage

BACKGROUND

Approximately 10% of cases of hypertensive intracerebral hemorrhage are cerebellar hemorrhage. We report a case of intracerebellar hemorrhage in which the initial symptoms were hearing loss and tinnitus.

SUMMARY OF REPORT

A 45-year-old man suddenly complained of hearing loss and tinnitus on the right side. Computed tomography demonstrated a high-density area 1.2 cm in diameter in the right cerebellar peduncle. Because of enlargement of the high-density area, the patient underwent surgery based on the diagnosis of hypertensive intracerebellar hemorrhage, and the hematoma was evacuated. The right-sided acoustic nerve was remarkably swollen by a subpial hematoma.

CONCLUSIONS

In this case, hemorrhage of the right cerebellar peduncle extended to the eighth nerve through the subpial space, causing hearing loss and tinnitus.

Central Nervous Activity upon Systemic Salicylate Application in Animals with Kanamycin-Induced Hearing Loss--A Manganese-Enhanced MRI (MEMRI) Study

This study investigated the effect of systemic salicylate on central auditory and non-auditory structures in mice. Since cochlear hair cells are known to be one major target of salicylate, cochlear effects were reduced by using kanamycin to remove or impair hair cells. Neuronal brain activity was measured using the non-invasive manganese-enhanced magnetic resonance imaging technique. For all brain structures investigated, calcium-related neuronal activity was increased following systemic application of a sodium salicylate solution: probably due to neuronal hyperactivity. In addition, it was shown that the central effect of salicylate was not limited to the auditory system. A general alteration of calcium-related activity was indicated by an increase in manganese accumulation in the preoptic area of the anterior hypothalamus, as well as in the amygdala. The present data suggest that salicylate-induced activity changes in the auditory system differ from those shown in studies of noise trauma. Since salicylate action is reversible, central pharmacological effects of salicylate compared to those of (permanent) noise-induced hearing impairment and tinnitus might induce different pathophysiologies. These should therefore, be treated as different causes with the same symptoms.

Genome-first approach to rare EYA4 variants and cardio-auditory phenotypes in adults

While newborns and children with hearing loss are routinely offered genetic testing, adults are rarely clinically tested for a genetic etiology. One clinically actionable result from genetic testing in children is the discovery of variants in syndromic hearing loss genes. EYA4 is a known hearing loss gene which is also involved in important pathways in cardiac tissue. The pleiotropic effects of rare EYA4 variants are poorly understood and their prevalence in a large cohort has not been previously reported. We investigated cardio-auditory phenotypes in 11,451 individuals in a large biobank using a rare variant, genome-first approach to EYA4. We filtered 256 EYA4 variants carried by 6737 participants to 26 rare and predicted deleterious variants carried by 42 heterozygotes. We aggregated predicted deleterious EYA4 gene variants into a combined variable (i.e. "gene burden") and performed association studies across phenotypes compared to wildtype controls. We validated findings with replication in three independent cohorts and human tissue expression data. EYA4 gene burden was significantly associated with audiometric-proven HL (p = [Formula: see text], Mobitz Type II AV block (p = [Formula: see text]) and the syndromic presentation of HL and primary cardiomyopathy (p = 0.0194). Analyses on audiogram, echocardiogram, and electrocardiogram data validated these associations. Prior reports have focused on identifying variants in families with severe or syndromic phenotypes. In contrast, we found, using a genotype-first approach, that gene burden in EYA4 is associated with more subtle cardio-auditory phenotypes in an adult medical biobank population, including cardiac conduction disorders which have not been previously reported. We show the value of using a focused approach to uncover human disease related to pleiotropic gene variants and suggest a role for genetic testing in adults presenting with hearing loss.

Hearing impairment associated with spinal anesthesia

OBJECTIVES

Hearing loss after spinal anesthesia has been reported to be related to the transmission of a reduced subarachnoid pressure to the inner ear via the cochlear aqueduct due to loss of spinal fluid. However, there are also some controversies related to this phenomenon, which require systematic investigation.

MATERIAL AND METHODS

The effect of spinal needle diameter on hearing loss was investigated using audiometric tests in a prospective comparative study of 30 patients who were scheduled for surgery with spinal anesthesia. The bony structure of the cochlear and vestibular aqueducts was determined from temporal bone CT scans.

RESULTS

Four out of 15 patients (26.67%) treated with a 22 G spinal needle demonstrated hearing loss the day after surgery, which recovered within 2-5 weeks. However, none of the patients treated with a 27 G spinal needle had statistically significant hearing loss in either ear at any frequency. Three out of four patients with hearing loss had an acute-onset balance problem. There was no difference between the two groups in terms of the widths of the vestibular and cochlear aqueducts.

CONCLUSIONS

It has been shown audiometrically that the diameter of the spinal needle used to induce spinal anesthesia seems to have an effect on subsequent hearing loss. The patency of the bony canal determines the transmission of pressure changes to the inner ear. However, the individual risk of this complication is not predictable as there is no radiological abnormality of the canal.

[The deaf child: anatomy, etiologies and management]

Temporal bone imaging in children shows radioanatomical aspects and diseases distinct from the imaging and pathology results found in adults. Imaging modalities such as CT and MR bring out these differences. The aim of this study is to present the CT and MR particularities of the temporal bone during postnatal growth. The mastoid air cells form mostly in the postnatal period and the course of pneumatization is directly correlated with middle ear successive inflammatory episodes. The most frequent etiologies of hearing loss in children are reviewed, emphasizing their specificities in clinical presentation, radiological aspects, and treatment. In children, conductive hearing loss with normal tympanic membrane is mostly caused by minor aplasia rather than otosclerosis. Sensorineural hearing loss, even when unilateral, is predominantly due to malformation or infection and in rare cases to posterior fossa tumor.

Longitudinal Changes in Resting-State Functional Connectivity and Gray Matter Volume Are Associated with Conversion to Hearing Impairment in Older Adults

BACKGROUND

Hearing loss was recently identified as a modifiable risk factor for dementia although the potential mechanisms explaining this relationship are unknown.

OBJECTIVE

The current study examined longitudinal change in resting-state fMRI functional connectivity and gray matter volume in individuals who developed a hearing impairment compared to those whose hearing remained normal.

METHODS

This study included 440 participants from the UK Biobank: 163 who had normal hearing at baseline and impaired hearing at follow-up (i.e., converters, mean age = 63.11±6.33, 53% female) and 277 who had normal hearing at baseline and maintained normal hearing at follow-up (i.e., non-converters, age = 63.31±5.50, 50% female). Functional connectivity was computed between a priori selected auditory seed regions (left and right Heschl's gyrus and cytoarchitectonic subregions Te1.0, Te1.1, and Te1.2) and select higher-order cognitive brain networks. Gray matter volume within these same regions was also obtained.

RESULTS

Converters had increased connectivity from left Heschl's gyrus to left anterior insula and from right Heschl's gyrus to right anterior insula, and decreased connectivity between right Heschl's gyrus and right hippocampus, compared to non-converters. Converters also had reduced gray matter volume in left hippocampus and left lateral visual cortex compared to non-converters.

CONCLUSION

These findings suggest that conversion to a hearing impairment is associated with altered brain functional connectivity and gray matter volume in the attention, memory, and visual processing regions that were examined in this study.

A case of hearing loss and quadriplegia after a pontine hemorrhage

We herein describe the case of a 50-year-old female who developed a pontine hemorrhage with consciousness disturbance and quadriplegia. Her respiratory condition was so bad that she needed to be intubated and put on artificial respiration. After her consciousness and respiratory condition gradually recovered, we noticed that she had developed a bilateral hearing loss. The auditory brain stem response test revealed only I waves on both sides, thus suggesting that her hearing loss had been caused by an injury to the hearing-conducting pathway including the cochlear nuclei. In this case, the hematoma extended from the lower to the upper part of pons and, furthermore, it was also located broadly in the dorsal part of the pons. As a result, the cochlear nuclei and corpus trapezoideum appeared to have been destroyed by the hematoma. However, since most cases with a brain stem hemorrhage showing bilateral hearing loss tend to be in a severe condition, this condition is often easy to overlook. We should therefore carefully evaluate patients' reaction to hearing stimulation to avoid overlooking any hearing loss in such patients.

The potential protective effects of temporal bone pneumatization: A shock absorber in temporal bone fracture

Objectives

We hypothesize that when temporal bone fractures occur, the pneumatic cells in the temporal bone are able to absorb most of the impact force during a traumatic event. This study aims to correlate the degree of pneumatization of the temporal bone with the severity of temporal bone fracture (TBF).

Methods

Charts and computed tomography scans representing 54 TBFs, diagnosed from 2012 to 2017 at a single tertiary hospital, were retrospectively reviewed. Temporal bone pneumatization (TBP) in the petrous apex and mastoid region was evaluated using previously published classification systems. TBP classifications and fracture types were correlated with TBF complications such as sensorineural hearing loss (SNHL), facial nerve palsy (FNP), and vestibular dysfunction.

Results

Patients with increased pneumatization of the temporal bone had significantly fewer and less severe SNHL. SNHL more strongly correlated with the degree of pneumatization in the mastoid (P = 0.005) than that in the petrous apex (P = 0.024). On the other hand, the degree of TBP correlated poorly with FNP and vestibular dysfunction. However, the mastoid hypopneumatization demonstrated significant correlation with otic-capsule violations (P = 0.002). Fractures with otic-capsule violation were 4 times more likely to have vestibular dysfunction (P = 0.043) and 3 times more likely to have SNHL (P = 0.006). FNP was not associated with otic-capsule violating fractures but was 3.5 times more common in comminuted fractures (P = 0.025).

Conclusions

The degree of temporal bone pneumatization was negatively correlated to the incidence of otic-capsule violation and the severity of hearing impairment in patients with temporal bone fracture. This study substantiated the potential protective effect of temporal bone pneumatization in TBFs.

A tumour in the cerebellopontine angle region: an unusual case

This paper describes a nearly 60-year old patient with unilateral hearing loss, developed in one year, and complaints of tinnitus and dizziness. Additional findings were unilateral peripheral facial paresis and a diminished corneal reflex. The cause was found to be a metastasis of an anaplastic carcinoma, localized at the site of the internal acoustic porus.

Brain Functional Alterations in Long-term Unilateral Hearing Impairment

BACKGROUND

The rate of patients with unilateral hearing impairments (UHI) increase with age and are characterized by asymmetric auditory afferents in which auditory information is asymmetrically transmitted to the brain. Long-term bilateral hearing imbalance can cause abnormal functional changes in the cerebral cortex. However, the relationship between functional alterations in the brain and the severity of the hearing impairment remains unclear.

METHODS

This study included 33 patients with UHI (left-sided impairment in 17 and right-sided impairment in 16) and 32 healthy patients. All participants underwent resting-state, blood oxygen level dependent functional magnetic resonance imaging. Fractional amplitude of low frequency fluctuation (fALFF) values were calculated after data preprocessing and compared among the left-sided and right-sided impairment groups and the control group. Pure tone audiometry was used to evaluate patients' hearing impairment level. The correlation between fALFF values of abnormal brain regions and the duration and severity of hearing impairment was analyzed.

RESULTS

Results provide evidence for altered resting-state functional activities in the brain of patients with left or right long-term UHI, with significantly increased fALFF values in the Heschl's gyrus, superior temporal gyrus, and insula were observed. Moreover, complicated networks reorganization involved in the visual, cognitive, sensorimotor and information transmission functions except for the auditory function and some brain regions exhibited functional changes only in the one-sided impairment group. In addition, the severity of hearing impairment is related with the functional activities in the bilateral Heschl's gyrus, bilateral insula, right superior temporal gyrus, and left middle frontal gyrus.

CONCLUSION

In conclusion, alterations in functional activity are observed in the brains of patients with long-term hearing impairments and multiple brain regions within different functional networks are involved in the brain functional remodeling. The brain reintegration mechanism appears to be asymmetrical and the lateralization pattern in the contralateral brain hemisphere for auditory information processing related with the severity of hearing impairment.

The otolaryngologist's role in management of hearing loss in infancy and childhood

This article reviews the role of the otolaryngologist-head and neck surgeon-in the diagnosis and treatment of hearing loss in infants and young children. The otolaryngologist is well-versed in the anatomy, physiology, and pathophysiology of the auditory system, as well as the craniofacial syndromes that can involve the head and neck in combination with deafness. In this paper, the various causes of congenital hearing loss are described, as well as the steps required for proper diagnosis. Finally, surgeries used by otolaryngologists to treat childhood hearing loss, their indications, and outcomes, are discussed.

Morphological comparison of internal auditory canal diverticula in the presence and absence of otospongiosis on computed tomography and their impact on patterns of hearing loss

PURPOSE

The association of internal auditory canal (IAC) fundal diverticula with otospongiosis (OS) and their clinical significance remain unclear. We explored whether isolated IAC diverticula were morphologically different from those with additional CT features of OS, and whether IAC diverticula morphology influenced patterns of hearing loss.

METHODS

Consecutive temporal bone CT studies with (n = 978) and without (n = 306) features of OS were retrospectively assessed. Two independent observers evaluated the presence of IAC diverticula morphological features (depth, neck:depth ratio, definition of contour and angulation of shape), and these were correlated with the presence of fenestral and pericochlear OS. Audiometric profiles were analysed for the isolated IAC diverticula and those with fenestral OS alone. Continuous data was compared using Wilcoxon rank sum tests and categorical data with chi-squared and Fisher's exact tests.

RESULTS

Ninety-five isolated IAC diverticula were demonstrated in 54/978 patients (5.5%) without CT evidence of OS (31M, 23F, mean age 46), and 119 IAC diverticula were demonstrated in 71/306 patients (23%) with CT evidence of OS (23M, 48F, mean age 55). Reduced neck:depth ratio, ill definition and angulation were all significantly associated with the presence of pericochlear OS (p < 0.001), whilst only ill definition was associated with the presence of fenestral OS alone (p < 0.05). No morphological feature was associated with conductive hearing loss in isolated diverticula or with sensorineural hearing loss in diverticula with fenestral OS alone.

CONCLUSION

IAC diverticula associated with pericochlear OS demonstrate different morphological features from isolated IAC diverticula. There are no clear audiometric implications of these morphological features.

Prevalence of Scarpa's ganglion enhancement on high-resolution MRI imaging

BACKGROUND AND PURPOSE

The vestibular ganglion, or Scarpa's ganglion, is a cluster of afferent vestibular neurons within the internal auditory canal (IAC). There is minimal literature describing enhancement of this region on magnetic resonance imaging (MRI) and its correlation to clinical symptoms. Here, we sought to find the prevalence of enhancement at Scarpa's ganglion, and determine whether such enhancement correlates with demographics or clinical symptoms.

MATERIALS AND METHODS

A retrospective review was performed of consecutive patients with an MRI of the IAC between 3/1/2021 and 5/20/2021. Two neuroradiologists independently reviewed for T1 and FLAIR enhancement of the Scarpa's ganglion on post-contrast fat-saturated T1 and post-contrast FLAIR images. Discrepancies were agreed upon by consensus. Clinical variables (hearing loss, vestibular symptoms, tinnitus, and MRI indication) were gathered from a retrospective chart review.

RESULTS

Eighty-nine patients were included (51 female); the mean age was 58 (range 19-85). The most common MRI indication was hearing loss (n = 53). FLAIR enhancement was present on the right in 7 patients, on the left in 7 patients, and bilaterally in 6 patients. No enhancement was seen on post-contrast T1 images. There was no statistically significant correlation between consensus FLAIR on at least one side and age (p = .74), gender (p = .29), hearing loss (p = .32), hearing loss side (p = .39), type of hearing loss (p = .87), vestibular symptoms (p = .71), or tinnitus (p = .81).

CONCLUSIONS

Enhancement is present in the minority of patients on post-contrast FLAIR images. If seen, it should be considered an uncommon but not unexpected finding with no clinical significance.