Structural connectivity changes in unilateral hearing loss.

Network connectivity, as mapped by the whole brain connectome, plays a crucial role in regulating auditory function. Auditory deprivation such as unilateral hearing loss might alter structural network connectivity; however, these potential alterations are poorly understood. Thirty-seven acoustic neuroma patients with unilateral hearing loss (19 left-sided and 18 right-sided) and 19 healthy controls underwent diffusion-weighted and T1-weighted imaging to assess edge strength, node strength, and global efficiency of the structural connectome. Edge strength was estimated by pair-wise normalized streamline density from tractography and connectomics. Node strength and global efficiency were calculated through graph theory analysis of the connectome. Pure-tone audiometry and word recognition scores were used to correlate the degree and duration of unilateral hearing loss with node strength and global efficiency. We demonstrate significantly stronger edge strength and node strength through the visual network, weaker edge strength and node strength in the somatomotor network, and stronger global efficiency in the unilateral hearing loss patients. No discernible correlations were observed between the degree and duration of unilateral hearing loss and the measures of node strength or global efficiency. These findings contribute to our understanding of the role of structural connectivity in hearing by facilitating visual network upregulation and somatomotor network downregulation after unilateral hearing loss.

Post headshake nystagmus: further correlation with other vestibular test results.

BACKGROUND: It is generally accepted that headshake nystagmus (HSN) is generated from an asymmetrical peripheral vestibular input and a correlation exists between HSN and canal paresis. There have been limited reports, however, how HSN correlates with the more recently introduced tests of vestibular function. AIMS/OBJECTIVES: To evaluate the correlation between HSN and unilateral weakness on caloric testing, high-frequency vestibulo-ocular reflex (VOR) function on video head impulse testing (VHIT) and otolith function determined by vestibular evoked myogenic potentials (VEMPs). METHODS: A retrospective study of all patients who underwent complete vestibular function testing at our tertiary referral center from 2016 to 2019 was performed. Demographic data, clinical diagnosis (where available), the results of video-nystagmography, vHIT, and VEMPs were evaluated. RESULTS: Of the 1499 patients in the study period, 101 (6.7%) had HSN. Vestibular test abnormalities were more common in patients with HSN. The sensitivity of HSN for underlying pathology was low in comparison with vestibular testing. However, HSN demonstrated a high specificity. CONCLUSIONS AND SIGNIFICANCE: HSN generation is likely more complex than caloric-induced nystagmus, probably due to additional variables within the vestibular system. HSN may provide clinicians with additional information concerning high-frequency VOR function involving lateral semicircular and otolith dysfunction.

The Relationship Between Disorders of Bone Metabolism and Benign Paroxysmal Positional Vertigo: A Systematic Review.

OBJECTIVES: Several studies have reported an association between benign paroxysmal positional vertigo (BPPV) and bone mineral density or serum vitamin D levels. The aim of this review is to provide further clarification regarding the relationship between BPPV and calcium metabolism. DESIGN: PubMed and MEDLINE databases were systematically reviewed to identify all English language papers regarding the relationship between BPPV and the following terms: osteoporosis, osteopenia, bone mineral density, serum vitamin D levels, and bone metabolism. RESULTS: Of the 456 identified records, 28 studies were eligible for this review. Most were retrospective studies with inherent limitations and often conflicting results. While the literature is not conclusive, osteoporosis in patients of at least 50 years old appears to have an association with BPPV. Similarly, an association was observed between recurrent BPPV and vitamin D deficiency. CONCLUSION: There is only weak evidence to support the relationship between BPPV and osteoporosis or low serum 25-hydroxyvitamin D levels. Further prospective studies with more robust methodologies are needed to clarify the association between BPPV and disorders of bone metabolism.

Elevated ocular VEMP responses in the absence of a superior semicircular canal dehiscence.

BACKGROUND: Vestibular evoked myogenic potentials (VEMPs) have an accepted role in the diagnosis of the superior semicircular canal dehiscence (SSCD) syndrome. The current impression is that ocular VEMPs (oVEMPs) are more sensitive than cervical VEMPs (cVEMPs) for detecting a SSCD and that oVEMP testing in response to air conducted sound provides an excellent screening test without risk of radiation exposure from computerized tomography (CT). AIMS/OBJECTIVES: To report on patients with elevated oVEMP amplitudes but without evidence for a SSCD on multiplanar CT imaging. MATERIAL AND METHODS: Retrospective chart review of all patients referred for vestibular function testing to our department. Patients with oVEMP peak-to-peak amplitudes ≥17 µν without evidence for a SSCD on imaging were evaluated. RESULTS: 26 patients had oVEMP peak-to-peak amplitudes ≥17 µν with no evidence of a SSCD on imaging. The most common diagnosis was Meniere's disease in those identified. CONCLUSION AND SIGNIFICANCE: oVEMPs can provide false positive results for diagnosis of a SSCD and an elevated oVEMP amplitude in itself is insufficient for diagnosis of a SSCD.

Management of invasive intralabyrinthine cholesteatoma: Can one realistically preserve hearing when disease is medial to the otic capsule?

PURPOSE: To report our long-term results in surgical management of invasive intralabyrinthine cholesteatoma. MATERIAL AND METHODS: The study is a case series in a tertiary referral center. Retrospective chart review of all mastoid operations performed for chronic ear disease between 1994 and 2019 at University Health Network, Toronto. The type of surgery, intraoperative findings, hearing outcome, recurrence of disease and the need for revision surgery were evaluated. RESULTS: 10 cases of extensive petrous bone cholesteatoma medial to the otic capsule were identified in 616 mastoid surgeries. All but one patient with extensive petrous bone cholesteatoma who underwent an exteriorizing procedure to preserve cochlear function failed the first surgery. A second procedure was needed in all cases due to complications which included facial palsy, recurrent cholesteatoma or internal auditory canal (IAC) abscess. Hearing was not preserved in any patient. In contrast, 57 ears with cholesteatomatous labyrinthine fistula lateral to the otic capsule had matrix exteriorized and had very good long-term results. CONCLUSION: We were rarely able to preserve hearing in massive petrous bone cholesteatoma. There should be no hesitation to remove the otic capsule to exteriorize diseases even under circumstances where residual cochlear and vestibular function is present if required to provide a safe ear.

Photographic facial soft tissue analysis of healthy Iranian young adults: anthropometric and angular measurements.

BACKGROUND: Soft tissue profile can be widely different in various populations. Furthermore, this profile can be also continues to change throughout life. However, there are few studies that quantitatively evaluate the soft tissue profile in Iranian population. In order to determine normal reference values of facial parts in our populations, we aimed to measure standards for facial soft tissue parameters in Iranian young population. METHODS: The study samples included 155 medical students at the Firouzgar hospital in winter 2011. The soft tissue facial profiles were digitally analyzed using linear measurements and angles made with standardized photographic records, taken in a natural head position, to determine the average soft tissue facial profile for males and females. RESULTS: There was a statistically significant difference between males and females in 21 of our 26 measurements. The most prominent differences between the genders were observed in the measurements taken from the face region. Minimum frontal breadth and supraorbital breadth were larger in males than in females. Except for middle face height measurement, other horizontal and vertical measurements for the face were larger in males than in females, indicating wider and higher faces in men than in women. Some measurements of facial angles are discrepant between the two genders. CONCLUSION: Due to the specific features of Iranian facial soft tissue values and also observable differences in facial measurements and angles between men and women, the Iranian standard values on facial measurements and angles should be given more attention, especially by plastic and cosmetic surgeons.

Central Vestibular Dysfunction in Head Injury.

OBJECTIVES: This study aims to provide an overview of dizziness post head injury in those with prominent features for central vestibular dysfunction (CVD) in comparison to those with a post-traumatic peripheral vestibular etiology. STUDY DESIGN: Retrospective. SETTING: University Health Network (UHN) Workplace Safety and Insurance Board (WSIB) database from 1988 to 2018 were evaluated for post-traumatic dizziness. METHODS: The UHN WSIB neurotology database (n = 4291) between 1998 and 2018 was retrospectively studied for head-injured workers presenting with features for CVD associated with trauma. All patients had a detailed neurotological history and examination, audiovestibular testing that included video nystagmography (VNG) and cervical vestibular-evoked myogenic potentials (cVEMPs). Imaging studies including routine brain and high-resolution temporal bone computed tomography (CT) scans and/or intracranial magnetic resonance imaging (MRI) were available for the majority of injured workers. RESULTS: Among 4291 head-injured workers with dizziness, 23 were diagnosed with features/findings denoting CVD. Complaints of imbalance were significantly more common in those with CVD compared to vertigo and headache in those with peripheral vestibular dysfunction. Atypical positional nystagmus, oculomotor abnormalities and facial paralysis were more common in those with CVD. CONCLUSION: Symptomatic post-traumatic central vestibular injury is uncommon. It occurred primarily following high-impact trauma and was reflective for a more severe head injury where shearing effects on the brain often resulted in diffuse axonal injury. Complaints of persistent imbalance and ataxia were more common than complaints of vertigo. Eye movement abnormalities were highly indicative for central nervous system injury even in those with minimal change on CT/MRI.

Effectiveness of vestibular rehabilitation therapy in patients with idiopathic Cerebellar Ataxia with Bilateral Vestibulopathy (iCABV).

OBJECTIVE: To evaluate the benefit of vestibular rehabilitation therapy (VRT) in the management of patients with idiopathic cerebellar ataxia with bilateral vestibulopathy (iCABV). BACKGROUND: iCABV is a hindbrain degenerative disorder with impairment of both central and peripheral vestibular pathways. There is combined failure of four compensatory eye movement systems including the vestibulo-ocular reflex (VOR), optokinetic reflex, smooth pursuit and the visually enhanced vestibulo-ocular reflex (VVOR). Phenotypic presentation includes postural and gait instability, oscillopsia and dizziness with active head movement. The benefit of VRT in iCABV patients has not been established. METHODS: A retrospective review was performed on a cohort of twelve patients diagnosed with iCABV in a multidisciplinary neuro-otology clinic. All participated in VRT and completed their suggested course of VRT. The following clinical measures were assessed before starting and after finishing VRT: 1) Dizziness Handicap Inventory (DHI), 2) Activities-Specific Balance Confidence (ABC) Scale, 3) Catastrophization scale, 4) Positive Affective Negative Affective Score (PANAS), 5) Dynamic Gait Index (DGI) and 6) Modified Clinical Test of Sensory Interaction in Balance (mCTSIB). The number of falls historically was recorded in addition to gait speed (ft./sec). RESULTS: Following VRT, patients were found to have improved balance on mCTSIB (condition 4 : 7 vs 18 seconds, P = 0.04) and a better postural stability with a reduced number of falls (p = 0.01). No statistically significant improvement was seen in the DHI, ABC, Catastrophization scale, DGI, PANAS and gait speed (p > 0.05). CONCLUSIONS: iCABV patients who underwent VRT were found to have a better postural stability and reduced risk of falls. VRT was not found to significantly improve patients' overall subjective perception of their symptoms or their psychological status.

Contralesional High-Acceleration Vestibulo-Ocular Reflex Function in Vestibular Schwannoma.

Impairment of ipsilesional vestibulo-ocular reflex (VOR) function is well described in vestibular schwannoma (VS) and a correlation between gain of the VOR and tumor size has been suggested. Bilateral VOR impairment may also occur in VS patients, but its mechanisms are poorly understood. We sought to explore the effect of unilateral VS on ipsilesional and contralesional high-acceleration VOR function using video head impulse testing, and evaluate potential factors responsible for contralesional VOR impairment. MATERIALS AND METHODS: Chart review in tertiary referral center of patients with unilateral VS, who completed neurotological examination and vestibular function testing. RESULTS: One hundred one patients (mean age 57.4 yrs) were included. Maximal tumor diameter ranged from 0.3 to 5.0 cm. Forty one patients had evidence of brainstem compression from VS on magnetic resonance imaging (MRI). Ipsilesional and contralesional VOR impairment was present in 81 (80%) and 44 (43%) patients, respectively. Bilateral VOR impairment was seen in 42 (42%) patients. Bilateral VOR impairment correlated with tumor size. Presence of brainstem compression was associated with reduced ipsilesional VOR gain, but not contralesional VOR gain.

Post-traumatic peripheral vestibular disorders (excluding positional vertigo) in workers following head injury.

Benign paroxysmal positional vertigo has typically been reported to be the most common cause of post-traumatic dizziness. There is however paucity in the literature about other peripheral vestibular disorders post-head injury. This article provides an overview of other causes of non-positional dizziness post-head trauma from our large institutional experience. The UHN WSIB Neurotology database (n = 4291) between 1998 and 2018 was retrospectively studied for those head-injured workers presenting with non-positional peripheral vestibular disorders. All subjects had a detailed neurotological history and examination and vestibular testing including video nystagmography, video head impulse testing (or a magnetic scleral search coil study), vestibular-evoked myogenic potentials, and audiometry. Imaging studies included routine brain and high-resolution temporal bone CT scans and/or brain MRI. Based on a database of 4291 head-injured workers with dizziness, 244 were diagnosed with non-positional peripheral vertigo. Recurrent vestibulopathy (RV) was the most common cause of non-positional post-traumatic vertigo. The incidence of Meniere's disease in the post-traumatic setting did not appear greater than found in the general population. The clinical spectrum pertaining to recurrent vestibulopathy, Meniere's disease, delayed endolymphatic hydrops, drop attacks, superior semicircular canal dehiscence syndrome, and uncompensated peripheral vestibular loss are discussed.

Repair of large nasal septal perforation with titanium membrane: report of 10 cases.

OBJECTIVE: The aim of the study was to study a new treatment to repair large nasal septal perforation with medical titanium membrane. METHOD: Ten patients with septal perforation underwent repair with open rhinoplasty approach using titanium membrane. RESULTS: The perforation of nasal septum in 10 patients was closed satisfactorily. During our followup period (mean, 1 year), the titanium membrane was mucosalized, and this technique led to persistent closing of perforation. CONCLUSION: Repair of septal perforation with titanium membrane yields excellent results.

Transient Vertigo with Horizontal Nystagmus to Loud Noise and Pressure: Utricular Hydrops or Vestibular Atelectasis?

We present an unusual case of a patient with a positive Tullio phenomenon, brief Valsalva-induced transient horizontal nystagmus, reduced left caloric response, and bilateral vestibulo-ocular reflex loss. This study discusses the pathophysiology and differential diagnosis concerning the suspected pathology for the phenomenon of utricular hydrops or vestibular atelectasis and presents a literature review.

Long-Term Outcomes from Blind Sac Closure of the External Auditory Canal: Our Institutional Experience in Different Pathologies.

OBJECTIVES: This study reports long-term results of blind sac closure of the external auditory canal performed for various pathologies, compares the complication rates and the need for revision surgery. MATERIALS AND METHODS: This study is a retrospective review. Ninety-six cases of blind sac closure performed for various pathologies were included in this study. The primary pathologies included extensive mucosal disease in an open mastoid cavity, cholesteatoma, skull base lesion, cerebrospinal fluid leak, and osteoradionecrosis of the temporal bone. Preoperative history, postoperative complications, and the need for revision surgery were evaluated. RESULTS: The most common indication for blind sac closure in our series involved skull base lesions (62.5%). The mean follow-up period was 46 months (4 months - 20 years). The total complication rate related to blind sac closure was 10.4%. The median time between surgery and long-term complications was 5.5 years. Patients with chronic mucosal disease had the highest rate of complications. CONCLUSION: Blind sac closure of external meatus can be effectively performed for different pathologies. Long-term follow-up with patients is necessary. Patients with chronic mucosal disease have the highest complication rates.

Surgical Outcomes of Cerebellopontine angle Tumors in 50 Cases.

INTRODUCTION: To report our experience with a large series of surgical procedures for removal of cerebellopontine angle (CPA) tumors using different approaches. MATERIALS AND METHODS: This was a retrospective analysis of 50 patients (mean age, 49 years) with CPA tumors (predominantly acoustic neuroma) who underwent surgical removal using appropriate techniques (principally a translabyrinthine approach) during a 4-year period. RESULTS: One death occurred during this study. There were nine cases (18%) of cerebrospinal fluid leak, and five patients (10%) were diagnosed as having bacterial meningitis. Complete gross tumor removal was not achieved in four patients (8%). Facial nerve function as measured by the House Brackmann system was recorded in all patients 1 year following surgery: 32% had a score of 1 or 2; 26% had a score of 3 or 4; and 8% had a score of 5 or 6. Other complications included four cases of wound infection. CONCLUSION: The translabyrinthine approach was predominantly used in our series of CPA tumors, and complication rates were comparable with other large case series.

Occult Laryngeal Foreign Body Mimicking Normal Thyroid Cartilage.

INTRODUCTION: Foreign body aspiration is common especially in children. The absence of history of choking does not rule out the diagnosis. Diagnosis required high index of suspicion. CASE PRESENTATION: Undiagnosed foreign body aspiration mostly occurs in bronchial airway rather than larynx and can cause severe complications. In this article, we report a silent laryngeal foreign body aspiration to show that careful history taking and accurate evaluation of radiography are important factors for diagnosis. CONCLUSIONS: The single most significant factor leading to detect of tracheobronchial foreign body aspiration is a high index of suspicion; this case highlights the possibility of a foreign body in the airway in patients who presents with a recent onset of chronic respiratory complaints.

Myringoplasty using rotation flap of canal skin for total tympanic membrane perforation.

OBJECTIVE: To evaluate the efficacy of a novel technique of using rotation flap of canal skin in patients with total or subtotal tympanic membrane (TM) perforation with no anterior residual tympanic membrane. METHODS: A retrospective study of 50 patients with total or subtotal perforation repaired with rotation flap of canal skin. Clinical and audiometric data were recorded. RESULTS: The overall perforation closure rate was 96%. A statistically significant shortened healing time was observed. CONCLUSION: The rotation flap of canal skin could be an effective and safe technique for perforations with no anterior residual TM.

Effect of Intratympanic Dexamethasone on Controlling Tinnitus and Hearing loss in Meniere's Disease [corrected].

INTRODUCTION: We investigated the effect of intratympanic dexamethasone on control of tinnitus and hearing loss in patients with Menier's disease. MATERIALS AND METHODS: 100 consecutive patients with a diagnosis of Menier's disease according to the 1995 criteria of The American Academy of Otolaryngology - Head and Neck Surgery (AAO-HNS) who remained symptomatic despite medical therapy were assigned to receive intratympanic dexamethasone. The results were assessed with respect to changes in hearing symptoms and tinnitus. RESULTS: Hearing improvement and improvement in SDS was observed in 52% and 35% of patients, respectively. Tinnitus score was improved in 57% of patients. There was no relationship between age, sex, duration of disease, unilaterality of disease, or response to therapy. CONCLUSION: Intratympanic dexamethasone may be effective in the symptomatic control of hearing loss and tinnitus in Menier's disease.