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Uncompensated vestibular hypofunction can result in symptoms of dizziness, imbalance, and/or oscillopsia, gaze and gait instability, and impaired navigation and spatial orientation; thus, may negatively impact an individual's quality of life, ability to perform activities of daily living, drive, and work. It is estimated that one-third of adults in the United States have vestibular dysfunction and the incidence increases with age. There is strong evidence supporting vestibular physical therapy for reducing symptoms, improving gaze and postural stability, and improving function in individuals with vestibular hypofunction. The purpose of this revised clinical practice guideline is to improve quality of care and outcomes for individuals with acute, subacute, and chronic unilateral and bilateral vestibular hypofunction by providing evidence-based recommendations regarding appropriate exercises.These guidelines are a revision of the 2016 guidelines and involved a systematic review of the literature published since 2015 through June 2020 across 6 databases. Article types included meta-analyses, systematic reviews, randomized controlled trials, cohort studies, case-control series, and case series for human subjects, published in English. Sixty-seven articles were identified as relevant to this clinical practice guideline and critically appraised for level of evidence.Based on strong evidence, clinicians should offer vestibular rehabilitation to adults with unilateral and bilateral vestibular hypofunction who present with impairments, activity limitations, and participation restrictions related to the vestibular deficit. Based on strong evidence and a preponderance of harm over benefit, clinicians should not include voluntary saccadic or smooth-pursuit eye movements in isolation (ie, without head movement) to promote gaze stability. Based on moderate to strong evidence, clinicians may offer specific exercise techniques to target identified activity limitations and participation restrictions, including virtual reality or augmented sensory feedback. Based on strong evidence and in consideration of patient preference, clinicians should offer supervised vestibular rehabilitation. Based on moderate to weak evidence, clinicians may prescribe weekly clinic visits plus a home exercise program of gaze stabilization exercises consisting of a minimum of: (1) 3 times per day for a total of at least 12 minutes daily for individuals with acute/subacute unilateral vestibular hypofunction; (2) 3 to 5 times per day for a total of at least 20 minutes daily for 4 to 6 weeks for individuals with chronic unilateral vestibular hypofunction; (3) 3 to 5 times per day for a total of 20 to 40 minutes daily for approximately 5 to 7 weeks for individuals with bilateral vestibular hypofunction. Based on moderate evidence, clinicians may prescribe static and dynamic balance exercises for a minimum of 20 minutes daily for at least 4 to 6 weeks for individuals with chronic unilateral vestibular hypofunction and, based on expert opinion, for a minimum of 6 to 9 weeks for individuals with bilateral vestibular hypofunction. Based on moderate evidence, clinicians may use achievement of primary goals, resolution of symptoms, normalized balance and vestibular function, or plateau in progress as reasons for stopping therapy. Based on moderate to strong evidence, clinicians may evaluate factors, including time from onset of symptoms, comorbidities, cognitive function, and use of medication that could modify rehabilitation outcomes.Recent evidence supports the original recommendations from the 2016 guidelines. There is strong evidence that vestibular physical therapy provides a clear and substantial benefit to individuals with unilateral and bilateral vestibular hypofunction.The focus of the guideline was on peripheral vestibular hypofunction; thus, the recommendations of the guideline may not apply to individuals with central vestibular disorders. One criterion for study inclusion was that vestibular hypofunction was determined based on objective vestibular function tests. This guideline may not apply to individuals who report symptoms of dizziness, imbalance, and/or oscillopsia without a diagnosis of vestibular hypofunction.These recommendations are intended as a guide to optimize rehabilitation outcomes for individuals undergoing vestibular physical therapy. The contents of this guideline were developed with support from the American Physical Therapy Association and the Academy of Neurologic Physical Therapy using a rigorous review process. The authors declared no conflict of interest and maintained editorial independence.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A369).

BACKGROUND Translabyrinthine approaches (TLAs) for resection of skull base neoplasms are complex with variable reconstruction techniques. Fat grafts in conjunction with hydroxyapatite bone cement techniques have seldom been described in terms of possible superiority to other skull base reconstruction techniques. We sought to determine the impact of this skull base reconstruction technique on clinical outcomes and patient's satisfaction. METHOD We performed a retrospective analysis of all patients who underwent translabyrinthine approaches for resection of CPA lesions over a 5-year period. Both post-op objective and subjective markers of reconstruction, as well as postoperative complications, were collected and analyzed. RESULTS Sixty-nine patients were included, 34 underwent reconstruction with hydroxyapatite and fat (rHAC) and 35 with fat alone (rF). rHAC was associated with fewer cranial wound superficial infection/dehiscence (0% vs 14.3%; p = 0.029) and shorter length of stay (mean ± standard deviation) (6.9 ± 7.4 vs 4.4 ± 3.7 days, p = 0.008). Postoperative subjective characterization of rHAC demonstrated improved satisfaction scores (1.38 ± 0.5 vs 1.83 ± 1; p = 0.049) and fewer reports of post-operative irregularities (11.5% vs 37.5%; p = 0.017). CONCLUSION The use of hydroxyapatite for cranial reconstruction after translabyrinthine approaches has improved patient satisfaction and decreased cranial defects in our small series. Postoperative complications are consistent with other described methods, but with shorter hospital stay, decreased risk of superficial wound dehiscence/infection, and a perceived superiority in preventing percutaneous post-op CSF leaks.

Management of small vestibular schwannomas (VSs) remains controversial. When surgery is chosen, the preservation of facial and cochlear nerve function is a priority. In this report, we introduce and evaluate a technique to anatomically preserve the vestibular nerves to minimize manipulation and preserve the function of the facial and cochlear nerves. The vestibular nerve preservation technique was prospectively applied to resect small VS tumors in patients with serviceable preoperative hearing (American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) class A or B). Clinical and radiological data were recorded and analyzed. Ten patients met the inclusion criteria. The mean (SD) age was 40.4 (12.5) years. Follow-up ranged from 6 weeks to 2 years. The maximum tumor diameter parallel to the internal auditory canal ranged from 10 to 20 mm (mean, 14.9 (3.1) mm). There were three Koos grade 3 and seven Koos grade 2 tumors. Gross total resection was achieved in all cases. Both the facial and cochlear nerves were anatomically preserved in all cases. Postoperatively, 7 patients (70%) remained in the AAO-HNS class A or B hearing category. None of the patients had new vestibular symptoms, and all had House–Brackmann grade 1 facial function. Nervus intermedius dysfunction was observed in 1 patient preoperatively, which worsened postoperatively. Two patients had new nervus intermedius symptoms postoperatively. Improvement of facial nerve and hearing outcomes is feasible through the intentional preservation of the vestibular nerves in the resection of small VSs. Longer follow-up is required to rule out tumor recurrence.

Translabyrinthine approaches (TLAs) for resection of skull base neoplasms are complex with variable reconstruction techniques. Fat grafts in conjunction with hydroxyapatite bone cement techniques have seldom been described in terms of possible superiority to other skull base reconstruction techniques. We sought to determine the impact of this skull base reconstruction technique on clinical outcomes and patient's satisfaction.We performed a retrospective analysis of all patients who underwent translabyrinthine approaches for resection of CPA lesions over a 5-year period. Both post-op objective and subjective markers of reconstruction, as well as postoperative complications, were collected and analyzed.Sixty-nine patients were included, 34 underwent reconstruction with hydroxyapatite and fat (rHAC) and 35 with fat alone (rF). rHAC was associated with fewer cranial wound superficial infection/dehiscence (0% vs 14.3%; p = 0.029) and shorter length of stay (mean ± standard deviation) (6.9 ± 7.4 vs 4.4 ± 3.7 days, p = 0.008). Postoperative subjective characterization of rHAC demonstrated improved satisfaction scores (1.38 ± 0.5 vs 1.83 ± 1; p = 0.049) and fewer reports of post-operative irregularities (11.5% vs 37.5%; p = 0.017).The use of hydroxyapatite for cranial reconstruction after translabyrinthine approaches has improved patient satisfaction and decreased cranial defects in our small series. Postoperative complications are consistent with other described methods, but with shorter hospital stay, decreased risk of superficial wound dehiscence/infection, and a perceived superiority in preventing percutaneous post-op CSF leaks.

OBJECTIVES: To compare contralateral to ipsilateral stimulation with percutaneous and transcutaneous bone conduction implants. BACKGROUND: Bone conduction implants (BCIs) effectively treat conductive and mixed hearing losses. In some cases, such as in single-sided deafness (SSD), the BCI is implanted contralateral to the remaining healthy ear in an attempt to restore some of the benefits provided by binaural hearing. While the benefit of contralateral stimulation have been shown in at least some patients, it is not clear what cues or mechanisms contribute to this function. Previous studies have investigated the motion of the ossicular chain, skull, and round window in response to bone vibration. Here, we extend those reports by reporting simultaneous measurements of cochlear promontory velocity and intracochlear pressures during bone conduction stimulation with two common BCI attachments, and directly compare ipsilateral to contralateral stimulation. METHODS: Fresh-frozen whole human heads were prepared bilaterally with mastoidectomies. Intracochlear pressure (P(IC)) in the scala vestibuli (P(SV)) and tympani (P(ST)) was measured with fiber optic pressure probes concurrently with cochlear promontory velocity (V(Prom)) via laser Doppler vibrometry during stimulation provided with a closed-field loudspeaker or a bone conduction implant (BCI). Stimuli were pure tones between 120 – 10240 Hz, and response magnitudes and phases for P(IC) and V(Prom) were measured for air and bone conducted sound presentation. RESULTS: Contralateral stimulation produced lower response magnitudes and longer delays than ipsilateral in all measures, particularly for high frequency stimulation. Contralateral response magnitudes were lower than ipsilateral response magnitudes by up to 10–15 dB above ~2 kHz for a skin-penetrating abutment, which increased to 25–30 dB and extended to lower frequencies when applied with a transcutaneous (skin drive) attachment. CONCLUSION: Transcranial attenuation and delay suggest that ipsilateral stimulation will be dominant for frequencies over ~1 kHz, and that complex phase interactions will occur during bilateral or bimodal stimulation. These effects indicate a mechanism by which bilateral users could gain some bilateral advantage.

Objective There are no direct comparisons between the success of collagen allografts versus traditional autografts for tympanic membrane (TM) repair. We sought to compare success rates in a large series of patients undergoing tympanoplasty using collagen allografts versus autologous tissues. Study design Retrospective review. Setting Academic medical center. Subjects and methods Single institution retrospective chart review was performed for adult subjects with TM perforation undergoing tympanoplasty. Demographic, clinical, and surgical data were collected. Statistical analysis was completed using Rstudio. Each factor was examined to assess effect on graft success rate using logistic regression. Results Two hundred sixty-five surgeries met criteria with four main grafting materials or combinations thereof. The overall graft success rate was 81.1% with failure rate of 18.9%. There was no significant association between failure rates and: age, sex, perforation cause, size, and location, primary or revision status, middle ear status (wet or dry), concomitant procedures (mastoidectomy or ossiculoplasty), presence of active cholesteatoma, or surgical technique. Although not statistically significant, the odds of success for perichondrium + cartilage were 7.5 times higher than collagen allografts (p = 0.07, 95% confidence interval [CI] = 0.81-69.6). The odds of success for the postauricular (odds ratio [OR] = 6.4) and transcanal approaches (OR = 24.8) were significantly greater than for endaural (p = 0.007 and p = 0.008, respectively). Conclusion In tympanoplasty surgeries performed on patients with TM perforation, we found no statistically significant difference in graft failure rates between collagen allograft and other grafting materials or combinations, though the higher odds ratio of success with cartilage + perichondrium may be clinically relevant.

OBJECTIVE Current clinical practice for fixation of the cochlear implant receiver-stimulator (RS) may not follow recommended manufacturer's guidelines. We investigated short- and long-term RS migration using a subperiosteal pocket technique via serial objective position measurements since previous literature provided only subjective or short-term evaluation. STUDY DESIGN Retrospective review. SETTING Tertiary referral center. PATIENTS We reviewed all patients who underwent cochlear implantation by the senior author between 2012 and 2018. At least two comparison measurements were available for 73 implants in 62 patients, 72.6% adults and 27.4% children. INTERVENTIONS RS placement using a subperiosteal pocket technique. MAIN OUTCOME MEASURE Distance between the pinna and RS magnet in the early ( 6 mo) postoperative period. RESULTS In the early postoperative period, mean RS distance was 57.0 mm (SD 9.4 mm) from the pinna compared with baseline intraoperative distance of 55.8 mm (SD 8.4 mm), p = 0.44. With some shifts closer and some farther from the pinna, there was a 3.0 mm mean absolute value migration (median 2 mm, SD 3.8 mm, range 0-15 mm). Fourteen implants (25.9%) migrated >5 mm in the early period, 35.7% closer, and 64.3% farther from pinna. In the late postoperative period, mean RS final distance was 56.6 mm (SD 10.1 mm), compared with its baseline of 59.0 mm (SD 9.2 mm), p = 0.29. Seven implants (19.4%) demonstrated shifts >5 mm, with a mean 3.6 mm shift (median 2 mm, SD 4.5 mm, range 0-17 mm). CONCLUSION A subperiosteal pocket technique demonstrated objective RS migration in 20 to 25% of adult and pediatric patients, nearly all of which were not clinically apparent unless measured. Additionally, none of these patients experienced associated symptoms or device failures.

Otitis media (OM), a very common disease in young children, can result in hearing loss. In order to potentially replicate previously reported associations between OM and PLG, exome and Sanger sequencing, RNA-sequencing of saliva and middle ear samples, 16S rRNA sequencing, molecular modeling, and statistical analyses including transmission disequilibrium tests (TDT) were performed in a multi-ethnic cohort of 718 families and simplex cases with OM. We identified four rare PLG variants c.112A > G (p.Lys38Glu), c.782G > A (p.Arg261His), c.1481C > T (p.Ala494Val) and c.2045 T > A (p.Ile682Asn), and one common variant c.1414G > A (p.Asp472Asn). However TDT analyses for these PLG variants did not demonstrate association with OM in 314 families. Additionally PLG expression is very low or absent in normal or diseased middle ear in mouse and human, and salivary expression and microbial α-diversity were non-significant in c.1414G > A (p.Asp472Asn) carriers. Based on molecular modeling, the novel rare variants particularly c.782G > A (p.Arg261His) and c.2045 T > A (p.Ile682Asn) were predicted to affect protein structure. Exploration of other potential disease mechanisms will help elucidate how PLG contributes to OM susceptibility in humans. Our results underline the importance of following up findings from genome-wide association through replication studies, preferably using multi-omic datasets.

Previous genetic studies on susceptibility to otitis media and airway infections have focused on immune pathways acting within the local mucosal epithelium, and outside of allergic rhinitis and asthma, limited studies exist on the overlaps at the gene, pathway or network level between the upper and lower airways. In this report, we compared [1] pathways identified from network analysis using genes derived from published genome-wide family-based and association studies for otitis media, sinusitis, and lung phenotypes, to [2] pathways identified using differentially expressed genes from RNA-sequence data from lower airway, sinus, and middle ear tissues, in particular cholesteatoma tissue compared to middle ear mucosa. For otitis media, a large number of genes (n = 1,806) were identified as differentially expressed between cholesteatoma and middle ear mucosa, which in turn led to the identification of 68 pathways that are enriched in cholesteatoma. Two differentially expressed genes CR1 and SAA1 overlap in middle ear, sinus, and lower airway samples and are potentially novel genes for otitis media susceptibility. In addition, 56 genes were differentially expressed in both tissues from the middle ear and either sinus or lower airways. Pathways that are common in upper and lower airway diseases, whether from published DNA studies or from our RNA-sequencing analyses, include chromatin organization/remodeling, endocytosis, immune system process, protein folding, and viral process. Taken together, our findings from genetic susceptibility and differential tissue expression studies support the hypothesis that the unified airway theory wherein the upper and lower respiratory tracts act as an integrated unit also applies to infectious and nonallergic airway epithelial disease. Our results may be used as reference for identification of genes or pathways that are relevant to upper and lower airways, whether common across sites, or unique to each disease.

Objective To date, less than 150 cases of middle ear adenomatous neuroendocrine tumors (MEANTs) have been reported in the English literature. The objective of this study was to provide a contemporary analysis of these rare lesions and develop a consensus-driven staging system. Study design Multi-institutional retrospective histopathologic, radiologic, and clinical review. Setting Six tertiary referral centers. Patients Thirty-two patients with pathologically confirmed MEANT. Intervention Surgical resection, adjuvant therapy. Main outcome measures Clinical manifestations, outcomes, staging system. Results Patients commonly presented with progressive conductive or mixed hearing loss (90%), aural fullness (50%), and tonal tinnitus (46%). Pulsatile tinnitus (16%), carcinoid syndrome (4%), and facial nerve paresis (4%) were less commonly observed. MEANTs frequently mimicked temporal bone paraganglioma (31%) and cholesteatoma (15%) at presentation. According to a novel T/N/M/S staging system (S = secretory tumor) proposed herein, there were 6 (19%) T1, 19 (59%) T2, and 7 (22%) T3 MEANTs. T3 tumors were significantly more likely to undergo subtotal or near total resection compared with lower staged tumors secondary to adherence to critical neurovascular structures such as the petrous internal carotid artery and facial nerve (p = 0.027). Patients with T3 MEANTs were more likely to experience multiple recurrences, require adjuvant therapy with a somatostatin analogue, or develop permanent facial nerve paresis compared with lower staged tumors. At last follow up, no patients with T1 MEANTs had developed recurrence, whereas 37% (7/19) of patients with T2 MEANT and 57% (4/7) of patients with T3 MEANT experienced either disease recurrence after gross total resection (GTR) or regrowth of known residual tumor requiring additional surgery at a median duration of 72 months (95% CI, 24-84). Conclusions Patients with MEANTs can present with nonspecific symptomatology that overlaps with more commonly encountered middle ear lesions. MEANT exhibits a proclivity for recurrence according to T-stage and long-term clinical follow up is necessary, particularly for advanced stage tumors.

HYPOTHESIS: Insertion of cochlear implant electrodes generates transient pressure spikes within the vestibular labyrinth equivalent to high intensity acoustic stimuli. BACKGROUND: Though cochlear implant (CI) surgery is regarded as having low-risk of impacting the vestibular system, several studies have documented changes in vestibular function after implantation. The mechanism of these changes is not understood. We have previously established that large, potentially-damaging pressure transients can be generated in the cochlea during electrode insertion, but whether pressure transients occur within the vestibular labyrinth has yet to be determined. Here, we quantify the exposure of the vestibular system to potentially-damaging pressure transients during CI surgery. METHODS: Five human cadaveric heads were prepared with an extended facial recess and implanted sequentially with eight different CI electrode styles via a round window approach. Fiber-optic sensors measured intralabyrinthine pressures in scala vestibuli (SV), scala tympani (ST), and the lateral semicircular canal (LSCC) during insertions. RESULTS: Electrode insertion produced a range of high-intensity pressure spikes simultaneously in the cochlea and LSCC with all electrodes tested. Pressure transients recorded were found to be significantly higher in the vestibular labyrinth than the cochlea and occurred at peak levels known to cause acoustic trauma. CONCLUSION: Insertion of CI electrodes can produce transients in intralabyrinthine fluid pressure levels equivalent to high-intensity, impulsive acoustic stimuli. Results from this investigation affirm the importance of atraumatic surgical techniques and suggest that in addition to the cochlea, the vestibular system is potentially exposed to damaging fluid pressure waves during cochlear implantation.

Objectives (1) Evaluate changes in subjective symptoms in patients following transmastoid canal plugging for superior semicircular canal dehiscence (SSCD) syndrome. (2) Quantify changes in hearing in patients who have undergone transmastoid canal plugging for SSCD syndrome. Study Design Case series with chart review. Setting Single tertiary care institution. Subjects and Methods We retrospectively reviewed patients with SSCD who underwent repair with canal plugging via a transmastoid approach between January 2012 and January 2017. Symptom severity was assessed prospectively (autophony, sound/pressure-induced vertigo, disequilibrium, aural fullness, and pulsatile tinnitus) and after surgery. Pure-tone and speech audiometry were measured before and after surgery. Two-sided Wilcoxon rank-sum tests were used to evaluate changes in subjective symptoms and audiometric outcomes. Results Seventeen patients (19 ears) met inclusion criteria. The superior canal was successfully plugged via the transmastoid approach in all cases. Patients reported a statistically significant improvement in autophony, vertigo, aural fullness, and pulsatile tinnitus ( P < .01), without significant improvement in disequilibrium rating ( P = .06). There were no changes noted in pure-tone average or word recognition score; however, there was a statistically significant improvement in air-bone gap at 250 Hz of 10.9 dB ( P = .04) with 12.9-dB improvement in air conduction thresholds ( P = .02) and no difference (0.9 dB, P = .9) in bone conduction thresholds. Conclusion In our study, patients with SSCD demonstrated excellent hearing outcomes and resolution of most otologic symptoms after surgical repair. Transmastoid canal plugging, which has been described to date only in smaller case series, is a safe and effective alternative to the traditional middle cranial fossa approach.

Intracochlear pressures (PIC) and stapes velocity (Vstap) elicited by bilaterally placed bone-anchored hearing devices (BAHD) will be systematically modulated by imposed interaural time (ITD) and level differences (ILD), demonstrating the potential for users of bilateral BAHD to access these binaural cues.BAHD are traditionally implanted unilaterally under the assumption that transcranial cross-talk limits interaural differences. Recent studies have demonstrated improvements in binaural and spatial performance with bilateral BAHD; however, objective measures of binaural cues from bilateral BAHDs are lacking.Bone-conduction transducers were coupled to both mastoids of cadaveric specimens via implanted titanium abutments. PIC and Vstap were measured using intracochlear pressure probes and laser Doppler vibrometry, respectively, during stimulation with pure-tone stimuli of varied frequency (250-4000 Hz) under ipsilateral, contralateral, and bilateral ITD (-1 to 1 ms) and ILD (-20 to 20 dB) conditions.Bilateral stimulation produced constructive and destructive interference patterns that varied dramatically with ITD and stimulus frequency. Variation of ITD led to large variation of PIC and Vstap, with opposing effects in ipsilateral and contralateral ears expected to lead to "ITD to ILD conversion." Variation of ILD produced more straightforward (monotonic) variations of PIC and Vstap, with ipsilateral-favoring ILD producing higher PIC and Vstap than contralateral-favoring.Variation of ITDs and ILDs conveyed by BAHDs systematically modulated cochlear inputs. While transcranial cross-talk leads to complex interactions that depend on cue type and stimulus frequency, binaural disparities potentiate binaural benefit, providing a basis for improved sound localization and speech-in-noise perception.

We present a case of a 23-month old female with congenital malformation of her inner ear and perilymphatic fistula due to stapes footplate defect leading to recurrent episodes of bacterial meningitis and resulting bilateral profound hearing loss. Multiple-layer closure with obliteration of the malformation, middle ear and mastoid along with closure of the external auditory canal was performed to achieve definitive repair. Cochlear implantation in the contralateral ear resulted in age-appropriate language proficiency with excellent CI speech perception over a 12-year follow up. The importance of multiple-layer closure for adequate repair and early consideration of cochlear implantation are highlighted.

HYPOTHESIS: Acoustic stimulation generates measurable sound pressure levels in the semicircular canals. BACKGROUND: High-intensity acoustic stimuli can cause hearing loss and balance disruptions. To examine the propagation of acoustic stimuli to the vestibular end-organs, we simultaneously measured fluid pressure in the cochlea and semicircular canals during both air- and bone-conducted sound presentation. METHODS: Five full-cephalic human cadaveric heads were prepared bilaterally with a mastoidectomy and extended facial recess. Vestibular pressures were measured within the superior, lateral and posterior semicircular canals and referenced to intracochlear pressure within the scala vestibuli with fiber-optic pressure probes. Pressures were measured concurrently with laser Doppler vibrometry measurements of stapes velocity during stimulation with both air- and bone-conduction. Stimuli were pure tones between 100 Hz and 14 kHz presented with custom closed-field loudspeakers for air-conducted sounds and via commercially available bone-anchored device for bone-conducted sounds. RESULTS: Pressures recorded in the superior, lateral and posterior semicircular canals in response to sound stimulation were equal to or greater in magnitude than those recorded in the scala vestibuli (up to 20 dB higher). The pressure magnitudes varied across canals in a frequency-dependent manner. CONCLUSIONS: High sound pressure levels were recorded in the semicircular canals with sound stimulation, suggesting that similar acoustical energy is transmitted to the semicircular canals and the cochlea. Since these intralabyrinthine pressures exceed intracochlear pressure levels, our results suggest that the vestibular end-organs may also be at risk for injury during exposure to high-intensity acoustic stimuli known to cause trauma in the auditory system.

Objective To assess long-term complication rate and parental satisfaction of osseointegrated bone conduction hearing implants (OBCHIs). Study Design Retrospective chart review of children undergoing OBCHIs. Methods A retrospective chart review of children undergoing OBCHIs for the treatment of conductive, mixed, and single-sided sensorineural hearing loss in children. Results Forty-five subjects were identified with 0.3 to 10.4 years of follow-up. The mean/median age and age range at implant were 9.0/7.8 and 1.7 to 19.1 years. The underlying hearing loss for the cohort included conductive (N = 30), sensorineural (N = 7), and mixed (N = 8) hearing loss. Conductive hearing loss, caused by aural atresia (62.9), was the most common indication for implantation. Fifty-eight complications occurred in 29 subjects, most related to skin infection or overgrowth. Seventeen events required revision surgery, and 18 required oral antibiotics and/or office-based cauterization. Children under the age of 5 years were more likely to have failure of osseointegration or require revision surgery. Parents of 33 subjects underwent a phone interview; 76% rated the overall satisfaction as satisfied or very satisfied. Conclusion A large percentage of children undergoing OBCHI develop postoperative complications, and up to 44% require revision surgery—a figure higher than generally reported and higher than in adults. No factors were found to adequately explain the higher complication rates in children compared to adults. Despite the occurrence of complications, parents viewed this device as satisfactory from many perspectives. Level of Evidence 4. Laryngoscope, 2017

BACKGROUND Combined electrical-acoustical stimulation (EAS) has gained popularity as patients with residual hearing are increasingly undergoing cochlear implantation. Preservation of residual hearing correlates with hearing outcomes, but loss of hearing occurs in a subset of these patients. Several mechanisms have been proposed as causing this hearing loss; we have previously described high amplitude pressure transients, equivalent to high-level noise exposures, in the inner ear during electrode insertion. The source of these transients has not been identified. METHODS Cadaveric human heads were prepared with an extended facial recess. Fiber-optic pressure sensors were inserted into the scala vestibuli and scala tympani to measure intracochlear pressures. Two cochlear implant (CI) electrode styles (straight and perimodiolar) were inserted during time-synced intracochlear pressures and video fluoroscopy measurements. RESULTS CI electrode insertions produced pressure transients in the cochlea up to 160 to 170 dB pSPL equivalent for both styles, consistent with previous results. However, the position of the electrode within the cochlea when transients were generated differed (particularly contact with the medial or lateral walls). CONCLUSIONS These results begin to elucidate the insertion pressure profiles of CI electrodes, which can be used to improve CI electrode designs and facilitate "silent-insertions" to improve chances of hearing preservation.

BACKGROUND Access to the jugular foramen (JF) requires extensive approaches. An endoscopic endonasal far medial (EEFM) approach combined with a postauricular transtemporal (PTT) approach may provide adequate exposure with limited morbidities. OBJECTIVE To provide a quantitative anatomic comparison of the EEFM, the PTT, and the combined EEFM/PTT approaches. A clinical case of the combined approach is presented. METHODS Five cadaveric heads were dissected. Each specimen received PTT and EEFM approaches on opposite sides followed by an EEFM approach on the side of the PTT approach. Morphometric and quadrant analyses were conducted. Three groups were obtained and compared: PTT (group A), EEFM (group B), and combined (group C). RESULTS Group B had a significantly higher area of exposure of the JF as compared to group A (112.3 and 225 mm2, respectively, P = .004). The average degree of freedom (DOF) in the cranio-caudal plane for groups A and B was 63.6 and 12.6 degrees, respectively (P

A genetic basis for otitis media is established, however, the role of rare variants in disease etiology is largely unknown. Previously a duplication variant within A2ML1 was identified as a significant risk factor for otitis media in an indigenous Filipino population and in US children. In this report exome and Sanger sequencing was performed using DNA samples from the indigenous Filipino population, Filipino cochlear implantees, US probands, Finnish, and Pakistani families with otitis media. Sixteen novel, damaging A2ML1 variants identified in otitis media patients were rare or low-frequency in population-matched controls. In the indigenous population, both gingivitis and A2ML1 variants including the known duplication variant and the novel splice variant c.4061 + 1 G>C were independently associated with otitis media. Sequencing of salivary RNA samples from indigenous Filipinos demonstrated lower A2ML1 expression according to the carriage of A2ML1 variants. Sequencing of additional salivary RNA samples from US patients with otitis media revealed differentially expressed genes that are highly correlated with A2ML1 expression levels. In particular, RND3 is upregulated in both A2ML1 variant carriers and high-A2ML1 expressors. These findings support a role for A2ML1 in keratinocyte differentiation within the middle ear as part of otitis media pathology and the potential application of ROCK inhibition in otitis media.

OBJECTIVES To translate and validate the Zurich Chronic Middle Ear Inventory (ZCMEI-21) for the English language in order to provide an English instrument to assess health-related quality of life in chronic otitis media (COM). DESIGN Pilot translation study including cognitive debriefings, prospective multicenter cross-sectional psychometric validation study. SETTING Four tertiary referral centers in three different English-speaking countries (United Kingdom, United States of America and Australia). PARTICIPANTS Adult patients suffering from COM. MAIN OUTCOME MEASURES The English translation of the ZCMEI-21 (ZCMEI-21-E) and the five-level version of the EQ-5D questionnaire. The EQ-5D, which constitutes a generic measure of health-related quality of life, consists of a descriptive system score and a visual analogue scale. Statistical outcomes included single item descriptive statistics, internal consistency (Cronbach's α) as an indicator of reliability, as well as construct validity. RESULTS A total of 124 patients suffering from COM were included. The mean age was 50.1 years (SD 16.9 years) and 72 (58.1%) were males. The Cronbach's α of the ZCMEI-21-E was 0.91, suggesting an excellent internal consistency. The Spearman's correlation coefficient of the ZCMEI-21-E total score was 0.55 (p < 0.0001) for convergent construct validity with EQ-5D descriptive system score and 0.57 (p < 0.0001) with the EQ-5D visual analogue scale. CONCLUSIONS The ZCMEI-21-E is a new validated questionnaire that provides clinicians with a short, comprehensive and reliable instrument to quantify health-related quality of life in patients suffering from COM. The ZCMEI-21-E may be of use in clinical routine as well as in outcome research and monitoring. This article is protected by copyright. All rights reserved.

To compare outcomes for patients undergoing a transmastoid approach versus a middle fossa craniotomy approach with plugging and/or resurfacing for repair of superior semicircular canal dehiscence. Outcome measures include symptom resolution, hearing, operative time, hospital stay, complications, and revision rates.Multicenter retrospective comparative cohort study.Three tertiary neurotology centers.All adult patients undergoing repair for superior canal dehiscence between 2006 and 2017 at 3 neurotology centers were included. Demographics and otologic history collected by chart review. Imaging, audiometric data, and vestibular evoked myogenic potential measurements were also collected for analysis.A total of 68 patients (74 ears) were included in the study. Twenty-one patients underwent middle fossa craniotomy repair (mean age, 47.9 years), and 47 underwent transmastoid repair (mean age, 48.0 years). There were no significant differences in age or sex distribution between the groups. The transmastoid group experienced a significantly shorter duration of hospitalization and lower recurrence rate as compared with the middle fossa craniotomy group (3.8% vs 33%). Both groups experienced improvement in noise-induced vertigo, autophony, pulsatile tinnitus, and nonspecific vertigo. There was no significant difference among symptom resolution between groups. Additionally, there was no significant difference in audiometric outcomes between the groups.Both the transmastoid approach and the middle fossa craniotomy approach for repair of superior canal dehiscence offer symptom resolution with minimal risk. The transmastoid approach was associated with shorter hospital stays and lower recurrence rate as compared with the middle fossa craniotomy approach.

There are no definitive curative or preventative therapies available for Meniere’s disease. Treatment modalities are based on several theories surrounding the possible causes of the disease, and treatment aims to reduce symptoms of vertigo and preserve hearing and balance function. Here, we describe medical management strategies of Meniere’s disease.

Hypothesis: A cochlear implant electrode within the cochlea contributes to the air-bone gap (ABG) component of postoperative changes in residual hearing after electrode insertion. Background: Preservation of residual hearing after cochlear implantation has gained importance as simultaneous electric-acoustic stimulation allows for improved speech outcomes. Postoperative loss of residual hearing has previously been attributed to sensorineural changes; however, presence of increased postoperative ABG remains unexplained and could result in part from altered cochlear mechanics. Here, we sought to investigate changes to these mechanics via intracochlear pressure measurements before and after electrode implantation to quantify the contribution to postoperative ABG. Methods: Human cadaveric heads were implanted with titanium fixtures for bone conduction transducers. Velocities of stapes capitulum and cochlear promontory between the two windows were measured using single-axis laser Doppler vibrometry and fiber-optic sensors measured intracochlear pressures in scala vestibuli and tympani for air- and bone-conducted stimuli before and after cochlear implant electrode insertion through the round window. Results: Intracochlear pressures revealed only slightly reduced responses to air-conducted stimuli consistent with previous literature. No significant changes were noted to bone-conducted stimuli after implantation. Velocities of the stapes capitulum and the cochlear promontory to both stimuli were stable after electrode placement. Conclusion: Presence of a cochlear implant electrode causes alterations in intracochlear sound pressure levels to air, but not bone, conducted stimuli and helps to explain changes in residual hearing noted clinically. These results suggest the possibility of a cochlear conductive component to postoperative changes in hearing sensitivity.

Supplemental Digital Content is Available in the Text., Background: Uncompensated vestibular hypofunction results in postural instability, visual blurring with head movement, and subjective complaints of dizziness and/or imbalance. We sought to answer the question, “Is vestibular exercise effective at enhancing recovery of function in people with peripheral (unilateral or bilateral) vestibular hypofunction?” Methods: A systematic review of the literature was performed in 5 databases published after 1985 and 5 additional sources for relevant publications were searched. Article types included meta-analyses, systematic reviews, randomized controlled trials, cohort studies, case control series, and case series for human subjects, published in English. One hundred thirty-five articles were identified as relevant to this clinical practice guideline. Results/Discussion: Based on strong evidence and a preponderance of benefit over harm, clinicians should offer vestibular rehabilitation to persons with unilateral and bilateral vestibular hypofunction with impairments and functional limitations related to the vestibular deficit. Based on strong evidence and a preponderance of harm over benefit, clinicians should not include voluntary saccadic or smooth-pursuit eye movements in isolation (ie, without head movement) as specific exercises for gaze stability. Based on moderate evidence, clinicians may offer specific exercise techniques to target identified impairments or functional limitations. Based on moderate evidence and in consideration of patient preference, clinicians may provide supervised vestibular rehabilitation. Based on expert opinion extrapolated from the evidence, clinicians may prescribe a minimum of 3 times per day for the performance of gaze stability exercises as 1 component of a home exercise program. Based on expert opinion extrapolated from the evidence (range of supervised visits: 2-38 weeks, mean = 10 weeks), clinicians may consider providing adequate supervised vestibular rehabilitation sessions for the patient to understand the goals of the program and how to manage and progress themselves independently. As a general guide, persons without significant comorbidities that affect mobility and with acute or subacute unilateral vestibular hypofunction may need once a week supervised sessions for 2 to 3 weeks; persons with chronic unilateral vestibular hypofunction may need once a week sessions for 4 to 6 weeks; and persons with bilateral vestibular hypofunction may need once a week sessions for 8 to 12 weeks. In addition to supervised sessions, patients are provided a daily home exercise program. Disclaimer: These recommendations are intended as a guide for physical therapists and clinicians to optimize rehabilitation outcomes for persons with peripheral vestibular hypofunction undergoing vestibular rehabilitation. Video Abstract available for more insights from the author (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A124).

Non-secretor status due tohomozygosity for the commonFUT2 variant c. 461G> A(p. Trp154*) is associated witheither risk for autoimmune diseases or protection against viral diarrhea and HIV. We determined the role of FUT2 in otitis media susceptibility by obtaining DNA samples from 609 multi-ethnic families and simplex case subjectswith otitis media. Exome and Sanger sequencing, linkage analysis, and Fisher exact and transmission disequilibrium tests (TDT) were performed. The common FUT2 c. 604C> T (p. Arg202*) variant co-segregates with otitismedia in a Filipino pedigree (LOD = 4.0). Additionally, a rare variant, c. 412C> T (p. Arg138Cys), is associated with recurrent/ chronic otitismedia in European-American children (p = 1.2310(-5)) and US trios (TDT p = 0.01). The c. 461G> A (p. Trp154*) variant was also overtransmitted in US trios (TDT p = 0.01) and was associated with shifts inmiddle ear microbiota composition (PERMANOVA p 20 were combined, FUT2 variantswere over-transmitted in trios (TDTp = 0.001). Fut2 is transiently upregulated inmouse middle ear after inoculation withnon-typeable Haemophilus influenzae. Four FUT2 variants-namely p. Ala104Val, p. Arg138Cys, p. Trp154*, and p. Arg202*-reduced A antigen in mutant-transfected COS-7 cells, while the nonsense variants also reduced FUT2 protein levels. Common and rare FUT2 variants confer susceptibility to otitis media, likely by modifying the middle ear microbiome through regulation of A antigen levels in epithelial cells. Our familiesdemonstratemarked intra-familial genetic heterogeneity, suggesting thatmultiple combinations of common and rare variants plus environmental factors influence the individual otitis media phenotype as a complex trait.

Hypothesis Cochlear implants (CIs) designed for hearing preservation will not alter mechanical properties of the middle and inner ears as measured by intracochlear pressure (P(IC)) and stapes velocity (Vstap). Background CIs designed to provide combined electroacoustic stimulation are now available. To maintain functional acoustic hearing, it is important to know if a CI electrode can alter middle or inner ear mechanics because any alteration could contribute to elevated low-frequency thresholds in electroacoustic stimulation patients. Methods Seven human cadaveric temporal bones were prepared, and pure-tone stimuli from 120 Hz to 10 kHz were presented at a range of intensities up to 110 dB sound pressure level. P(IC) in the scala vestibuli (P(SV)) and tympani (PST) were measured with fiber-optic pressure sensors concurrently with VStap using laser Doppler vibrometry. Five CI electrodes from two different manufacturers with varying dimensions were inserted via a round window approach at six different depths (16-25 mm). Results The responses of P(IC) and VStap to acoustic stimulation were assessed as a function of stimulus frequency, normalized to sound pressure level in the external auditory canal, at baseline and electrode-inserted conditions. Responses measured with electrodes inserted were generally within approximately 5 dB of baseline, indicating little effect of CI electrode insertion on P(IC) and VStap. Overall, mean differences across conditions were small for all responses, and no substantial differences were consistently visible across electrode types. Conclusion Results suggest that the influence of a CI electrode on middle and inner ear mechanics is minimal despite variation in electrode lengths and configurations.

Objective This update of a 2008 guideline from the American Academy of Otolaryngology-Head and Neck Surgery Foundation provides evidence-based recommendations to benign paroxysmal positional vertigo (BPPV), defined as a disorder of the inner ear characterized by repeated episodes of positional vertigo. Changes from the prior guideline include a consumer advocate added to the update group; new evidence from 2 clinical practice guidelines, 20 systematic reviews, and 27 randomized controlled trials; enhanced emphasis on patient education and shared decision making; a new algorithm to clarify action statement relationships; and new and expanded recommendations for the diagnosis and management of BPPV. Purpose The primary purposes of this guideline are to improve the quality of care and outcomes for BPPV by improving the accurate and efficient diagnosis of BPPV, reducing the inappropriate use of vestibular suppressant medications, decreasing the inappropriate use of ancillary testing such as radiographic imaging, and increasing the use of appropriate therapeutic repositioning maneuvers. The guideline is intended for all clinicians who are likely to diagnose and manage patients with BPPV, and it applies to any setting in which BPPV would be identified, monitored, or managed. The target patient for the guideline is aged ≥18 years with a suspected or potential diagnosis of BPPV. The primary outcome considered in this guideline is the resolution of the symptoms associated with BPPV. Secondary outcomes considered include an increased rate of accurate diagnoses of BPPV, a more efficient return to regular activities and work, decreased use of inappropriate medications and unnecessary diagnostic tests, reduction in recurrence of BPPV, and reduction in adverse events associated with undiagnosed or untreated BPPV. Other outcomes considered include minimizing costs in the diagnosis and treatment of BPPV, minimizing potentially unnecessary return physician visits, and maximizing the health-related quality of life of individuals afflicted with BPPV. Action Statements The update group made strong recommendations that clinicians should (1) diagnose posterior semicircular canal BPPV when vertigo associated with torsional, upbeating nystagmus is provoked by the Dix-Hallpike maneuver, performed by bringing the patient from an upright to supine position with the head turned 45° to one side and neck extended 20° with the affected ear down, and (2) treat, or refer to a clinician who can treat, patients with posterior canal BPPV with a canalith repositioning procedure. The update group made a strong recommendation against postprocedural postural restrictions after canalith repositioning procedure for posterior canal BPPV. The update group made recommendations that the clinician should (1) perform, or refer to a clinician who can perform, a supine roll test to assess for lateral semicircular canal BPPV if the patient has a history compatible with BPPV and the Dix-Hallpike test exhibits horizontal or no nystagmus; (2) differentiate, or refer to a clinician who can differentiate, BPPV from other causes of imbalance, dizziness, and vertigo; (3) assess patients with BPPV for factors that modify management, including impaired mobility or balance, central nervous system disorders, a lack of home support, and/or increased risk for falling; (4) reassess patients within 1 month after an initial period of observation or treatment to document resolution or persistence of symptoms; (5) evaluate, or refer to a clinician who can evaluate, patients with persistent symptoms for unresolved BPPV and/or underlying peripheral vestibular or central nervous system disorders; and (6) educate patients regarding the impact of BPPV on their safety, the potential for disease recurrence, and the importance of follow-up. The update group made recommendations against (1) radiographic imaging for a patient who meets diagnostic criteria for BPPV in the absence of additional signs and/or symptoms inconsistent with BPPV that warrant imaging, (2) vestibular testing for a patient who meets diagnostic criteria for BPPV in the absence of additional vestibular signs and/or symptoms inconsistent with BPPV that warrant testing, and (3) routinely treating BPPV with vestibular suppressant medications such as antihistamines and/or benzodiazepines. The guideline update group provided the options that clinicians may offer (1) observation with follow-up as initial management for patients with BPPV and (2) vestibular rehabilitation, either self-administered or with a clinician, in the treatment of BPPV.

HYPOTHESIS Cochlear implant (CI) electrode insertion into the round window induces pressure transients in the cochlear fluid comparable to high-intensity sound transients. BACKGROUND Many patients receiving a CI have some remaining functional hearing at low frequencies; thus, devices and surgical techniques have been developed to use this residual hearing. To maintain functional acoustic hearing, it is important to retain function of any hair cells and auditory nerve fibers innervating the basilar membrane; however, in a subset of patients, residual low-frequency hearing is lost after CI insertion. Here, we test the hypothesis that transient intracochlear pressure spikes are generated during CI electrode insertion, which could cause damage and compromise residual hearing. METHODS Human cadaveric temporal bones were prepared with an extended facial recess. Pressures in the scala vestibuli and tympani were measured with fiber-optic pressure sensors inserted into the cochlea near the oval and round windows, whereas CI electrodes (five styles from two manufacturers) were inserted into the cochlea via a round window approach. RESULTS Pressures in the scala tympani tended to be larger in magnitude than pressures in the scala vestibuli, consistent with electrode insertion into the scala tympani. CI electrode insertion produced a range of pressure transients in the cochlea that could occur alone or as part of a train of spikes with equivalent peak sound pressure levels in excess of 170 dB sound pressure level. Instances of pressure transients varied with electrode styles. CONCLUSION Results suggest electrode design, insertion mechanism, and surgical technique affect the magnitude and rate of intracochlear pressure transients during CI electrode insertion. Pressure transients showed intensities similar to those elicited by high-level sounds and thus could cause damage to the basilar membrane and/or hair cells.

To examine the incidence and effect of postoperative air-bone gaps in subjects who received cochlear implants for the purpose of hearing preservation.Prospective, multicenter, nonrandomized, repeated measures within subject design.Ten tertiary care institutions.Fifty adults participating in a multicenter clinical trial of the Cochlear Nucleus Hybrid implant system.Cochlear implantation with Hybrid L24 electrode. Audiometric testing including air and bone conductive thresholds and tympanometry preoperatively and at multiple time points postoperatively for 1 year.Average air-bone gaps (ABG) and percentage of patients with ABGs (≥15 dB HL) measured for each time point for 1 year postoperatively at 250, 500, and 1000 Hz. Correlation of tympanograms and ABGs.The mean ABGs at 250, 500, and 1000 Hz increased postoperatively (p 0.05). The percentage of patients found to have an ABG (≥15 dB HL) also increased postoperatively (p 0.05). ABGs persisted and were present at 1 year in60% of patients at 250 Hz, in38% at 500 Hz, and in50% at 1000 Hz in those with residual hearing. No significant relationships were found between abnormal tympanograms and ABG.The incidence of ABGs postoperatively is higher than previously expected and does not correlate to abnormalities on tympanometry. ABGs can adversely affect the fitting of postoperative residual hearing and associated functional benefit. Additionally, intraoperative strategies should be used to potentially reduce ABGs, and bone conduction thresholds should be measured postoperatively.

To assess long-term complication rate and parental satisfaction of osseointegrated bone conduction hearing implants (OBCHIs).Retrospective chart review of children undergoing OBCHIs.A retrospective chart review of children undergoing OBCHIs for the treatment of conductive, mixed, and single-sided sensorineural hearing loss in children.Forty-five subjects were identified with 0.3 to 10.4 years of follow-up. The mean/median age and age range at implant were 9.0/7.8 and 1.7 to 19.1 years. The underlying hearing loss for the cohort included conductive (N = 30), sensorineural (N = 7), and mixed (N = 8) hearing loss. Conductive hearing loss, caused by aural atresia (62.9), was the most common indication for implantation. Fifty-eight complications occurred in 29 subjects, most related to skin infection or overgrowth. Seventeen events required revision surgery, and 18 required oral antibiotics and/or office-based cauterization. Children under the age of 5 years were more likely to have failure of osseointegration or require revision surgery. Parents of 33 subjects underwent a phone interview; 76% rated the overall satisfaction as satisfied or very satisfied.A large percentage of children undergoing OBCHI develop postoperative complications, and up to 44% require revision surgery-a figure higher than generally reported and higher than in adults. No factors were found to adequately explain the higher complication rates in children compared to adults. Despite the occurrence of complications, parents viewed this device as satisfactory from many perspectives.4. Laryngoscope, 127:2165-2170, 2017.

Vestibular schwannoma is a benign tumor that affects 3% of the population, but accounts for 85% of tumors occurring at the cerebellopontine angle (CPA). In this case, we present a 48-year-old female with history of cholesteatoma on the right and chronic suppurative otitis media on the left who presented with an 18 month history of bilateral hearing loss, worse on the right. Investigations revealed a right sided vestibular schwannoma measuring 1.6 cm in diameter. Audiogram revealed an AAO–HNS (American Academy of Otolaryngology–Head and Neck Surgery) class C hearing on the right and class B on the left. There are several management options for this size of vestibular schwannoma including observation and radiosurgery. However, preserving cochlear nerve function remains a challenging enterprise. Furthermore, the ideal management that confers the highest chance of hearing preservation remains heavily debated. Given the patient's young age, the goal of hearing preservation and the tumor size/extension into the CPA, surgery was decided through a right retrosigmoid transmeatal approach for tumor resection with intraoperative brain auditory evoked responses monitoring. For hearing preservation, we emphasize few important dissection techniques: tumor debulking from the top first to avoid early manipulation of the cochlear nerve at the bottom of the tumor, sharp dissection from medial to lateral off the vestibular nerve which is kept intact as a tension band to minimize cochlear nerve manipulations, and limit the drilling of the posterolateral wall of the internal auditory canal (IAC) medial to the labyrinth and endolymphatic apparatus. Postoperatively, the patient was discharged home within 2 days, with imaging showing a gross total resection. Follow-up audiogram shows unchanged pure tone thresholds.The link to the Video can be found at: https://youtu.be/Z5ftkpJN5k8.

Although many previous experiments have considered the responses of vestibular nucleus neurons to rotations and translations of the head, little data are available regarding cells in the caudalmost portions of the vestibular nuclei (CVN), which mediate vestibulo-autonomic responses among other functions. This study examined the responses of CVN neurons of conscious cats to rotations in vertical planes, both before and after a bilateral vestibular neurectomy. None of the units included in the data sample had eye movement-related activity. In labyrinth-intact animals, some CVN neurons (22%) exhibited graviceptive responses consistent with inputs from otolith organs, but most (55%) had dynamic responses with phases synchronized with stimulus velocity. Furthermore, the large majority of CVN neurons had response vector orientations that were aligned either near the roll or vertical canal planes, and only 18% of cells were preferentially activated by pitch rotations. Sustained head-up rotations of the body provide challenges to the cardiovascular system and breathing, and thus the response dynamics of the large majority of CVN neurons were dissimilar to those of posturally-related autonomic reflexes. These data suggest that vestibular influences on autonomic control mediated by the CVN are more complex than previously envisioned, and likely involve considerable processing and integration of signals by brainstem regions involved in cardiovascular and respiratory regulation. Following a bilateral vestibular neurectomy, CVN neurons regained spontaneous activity within 24 h, and a very few neurons (10%) responded to vertical tilts15 degrees in amplitude. These findings indicate that nonlabyrinthine inputs are likely important in sustaining the activity of CVN neurons; thus, these inputs may play a role in functional recovery following peripheral vestibular lesions.

Homozygosity mapping within consanguineous families is a powerful method of localising genes for autosomal recessive disease. We investigated a family from Punjab, Pakistan, a region where consanguineous marriages are frequent. The parents have no detectable clinical disorders. However, five out of six children present with schizophrenia, epilepsy or hearing impairment either alone or in combination. This unusual phenotype in several offspring of first cousins is strongly suggestive of a rare, Mendelian recessive disorder. Two genome-wide scans initially using low-density microsatellites, and subsequently high-density SNP markers were used to map homozygous-by-descent regions in affected individuals. Candidate genes within these loci were subsequently screened for mutations. Homozygosity analysis and inbreeding coefficients were investigated to give an estimate of consanguinity. Two putative disease loci were mapped to 22q12.3-q13.3 and 2p24.3. The candidate locus on chromosome 2p24 overlaps with a deafness locus, DFNB47, linked to autosomal recessive hearing impairment, while positive findings reported for affective psychosis and schizophrenia cluster in a region of 4-5 cM on 22q13.1 within our second candidate locus. Sequence analysis of three candidate genes (KCNF1 (2p); ATF4, CACNG2 (22q)) did not reveal any exonic mutations. Inbreeding coefficients calculated for each family member support a very high degree of ancestral and recent inbreeding. The screening of other candidate genes located within these newly identified disease intervals on Chr2p24.3 and 22q12.3-q13.3 may lead to the discovery of causative variants, and consequent disrupted molecular pathways associated with this rare phenotype.

HYPOTHESIS Intracochlear sound pressures (PIC) and velocity measurements of the stapes, round window, and promontory (VStap/RW/Prom) will show frequency-dependent attenuation using magnet-based transcutaneous bone conduction implants (TCBCIs) in comparison with direct-connect skin-penetrating implants (DCBCIs). BACKGROUND TCBCIs have recently been introduced as alternatives to DCBCIs. Clinical studies have demonstrated elevated high-frequency thresholds for TCBCIs as compared with DCBCIs; however, little data exist examining the direct effect of skin thickness on the cochlear input signal using TCBCIs. METHODS Using seven cadaveric heads, PIC was measured in the scala vestibuli and tympani with fiber-optic pressure sensors concurrently with VStap/RW/Prom via laser Doppler vibrometry. Ipsilateral titanium implant fixtures were placed and connected to either a DCBCI or a TCBCI. Soft tissue flaps with varying thicknesses (no flap and 3, 6, and 9 mm) were placed successively between the magnetic plate and sound processor magnet. A bone conduction transducer coupled to custom software provided pure-tone stimuli between 120 and 10,240 Hz. RESULTS Stimulation via the DCBCI produced the largest response magnitudes. The TCBCI showed similar PSV/ST and VStap/RW/Prom with no intervening flap and a frequency-dependent nonlinear reduction of magnitude with increasing flap thickness. Phase shows a comparable dependence on transmission delay as the acoustic baseline, and the slope steepens at higher frequencies as flap thickness increases, suggesting a longer group delay. CONCLUSION Proper soft tissue management is critical to optimize the cochlear input signal. The skin thickness-related effects on cochlear response magnitudes should be taken into account when selecting patients for a TCBCI.

OBJECTIVE Cervical and ocular vestibular evoked myogenic potentials (cVEMPs and oVEMPs) are commonly used in evaluation of neurotologic disorders. We present a case of sudden bilateral hearing loss immediately after oVEMP and cVEMP testing. The hearing loss did not recover. To our knowledge, no previous case reports discuss sudden hearing loss, especially bilateral, associated with VEMP testing. PATIENT A single patient with sudden bilateral hearing loss that has persisted after cVEMP and oVEMP. INTERVENTION The patient had a history of chronic daily dizziness. She underwent vestibular function testing that included cVEMP and oVEMP testing. A significant bilateral sensorineural hearing loss was noted immediately after cVEMP and oVEMP testing and confirmed with audiometric testing. Despite the use of oral steroids, her hearing loss did not recover. MAIN OUTCOME MEASURES Serial audiograms, calculated maximum total sound energies to each ear. RESULTS Pre-VEMP versus post-VEMP audiograms show increased thresholds and decreased word recognition scores; total sound energy delivered to each ear shows significant sound exposure. CONCLUSION Although VEMP testing is thought to be safe and well tolerated, a significant amount of sound can be delivered to the cochlea, and certain individuals may be susceptible to acoustic trauma at these levels. We recommend limits for VEMP stimuli levels and attention to total sound exposure when multiple trials are used.

Previous experiments have demonstrated that the vestibular system contributes to regulating sympathetic nervous system activity, particularly the discharges of vasoconstrictor fibres. In the present study, we examined the physiological significance of vestibulosympathetic responses by comparing blood flow and vascular resistance in the forelimb and hindlimb during head-up tilt from the prone position before and after the removal of vestibular inputs through a bilateral vestibular neurectomy. Experiments were performed on conscious cats that were trained to remain sedentary on a tilt table during rotations up to 60 deg in amplitude. Blood flow through the femoral and brachial arteries was recorded during whole-body tilt using perivascular probes; blood pressure was recorded using a telemetry system and vascular resistance was calculated from blood pressure and blood flow measurements. In vestibular-intact animals, 60 deg head-up tilt produced ∼20% decrease in femoral blood flow and ∼37% increase in femoral vascular resistance relative to baseline levels before tilt; similar effects were also observed for the brachial artery (∼25% decrease in blood flow and ∼38% increase in resistance). Following the removal of vestibular inputs, brachial blood flow and vascular resistance during head-up tilt were almost unchanged. In contrast, femoral vascular resistance increased only ∼6% from baseline during 60 deg head-up rotation delivered in the first week after elimination of vestibular signals and ∼16% in the subsequent 3-week period (as opposed to the ∼37% increase in resistance that occurred before lesion). These data demonstrate that vestibular inputs associated with postural alterations elicit regionally specific increases in vascular resistance that direct blood flow away from the region of the body where blood pooling may occur. Thus, the data support the hypothesis that vestibular influences on the cardiovascular system serve to protect against the occurrence of orthostatic hypotension.

Prior studies have shown that removal of vestibular inputs produces lability in blood pressure during orthostatic challenges (Holmes MJ, Cotter LA, Arendt HE, Cass SP, and Yates BJ. Brain Res 938: 62–72, 2002; Jian BJ, Cotter LA, Emanuel BA, Cass SP, and Yates BJ. J Appl Physiol 86: 1552–1560, 1999). Furthermore, these studies led to the prediction that the blood pressure instability results in susceptibility for orthostatic intolerance. The present experiments tested this hypothesis by recording common carotid blood flow (CCBF) in conscious cats during head-up tilts of 20, 40, and 60° amplitudes, before and after the surgical elimination of labyrinthine inputs through a bilateral vestibular neurectomy. Before vestibular lesions in most animals, CCBF remained stable during head-up rotations. Unexpectedly, in five of six animals, the vestibular neurectomy resulted in a significant increase in baseline CCBF, particularly when the laboratory was illuminated; on average, basal blood flow measured when the animals were in the prone position was 41 ± 17 (SE) % higher after the first week after the lesions. As a result, even when posturally related lability in CCBF occurred after removal of vestibular inputs, blood supply to the head was not lower than when labyrinthine inputs were present. These data suggest that vestibular influences on cardiovascular regulation are more complex than previously appreciated, because labyrinthine signals appear to participate in setting basal rates of blood flow to the head in addition to triggering dynamic changes in the circulation to compensate for orthostatic challenges.

OBJECTIVE: Glomus jugulare tumors (GJT) have traditionally been treated by surgery or fractionated external beam radiation therapy (XRT). This study evaluates acute toxicity and short-term efficacy of single-fraction stereotactic radiosurgery (SRS) for the treatment of GJT.STUDY DESIGN AND SETTING: Eight patients (age range 28-74) with GJT underwent SRS (Brainlab linear accelerator) as primary treatment. A nominal dose of 15-16 Gy was prescribed. RESULTS: After undergoing SRS, 7 of 8 patients (87.5%) reported complete resolution of presenting symptoms. Follow-up MRIs showed tumor stabilization in 100% of patients. Transient vertigo occurred in one patient. One patient suffered acute GI upset and transient lower cranial neuropathy.CONCLUSION: Stereotactic radiosurgery is an effective alternative for patients with GJT in achieving tumor control and resolution of symptoms.EBM rating: C-4© 2006 American Academy of Otolaryngology–Head and Neck Surgery Foundation, Inc. All rights reserved.

Previous studies in humans showed that genioglossal muscle activity is higher when individuals are supine than when they are upright, and prior experiments in anesthetized or decerebrate animals suggested that vestibular inputs might participate in triggering these alterations in muscle firing. The present study determined the effects of whole body tilts in the pitch (nose-up) plane on genioglossal activity in a conscious feline model and compared these responses with those generated by roll (ear-down) tilts. We also ascertained the effects of a bilateral vestibular neurectomy on the alterations in genioglossal activity elicited by changes in body position. Both pitch and roll body tilts produced modifications in muscle firing that were dependent on the amplitude of the rotation; however, the relative effects of ear-down and nose-up tilts on genioglossal activity were variable from animal to animal. The response variability observed might reflect the fact that genioglossus has a complex organization and participates in a variety of tongue movements; in each animal, electromyographic recordings presumably sampled the firing of different proportions of fibers in the various compartments and subcompartments of the muscle. Furthermore, removal of labyrinthine inputs resulted in alterations in genioglossal responses to postural changes that persisted until recordings were discontinued ∼1 mo later, demonstrating that the vestibular system participates in regulating the muscle's activity. Peripheral vestibular lesions were subsequently demonstrated to be complete through the postmortem inspection of temporal bone sections or by observing that vestibular nucleus neurons did not respond to rotations in vertical planes.

Prior work has shown that the vestibular system contributes to regulating activity of upper airway muscles including the tongue protruder muscle genioglossus. The goal of the present experiments was to determine whether electrical vestibular stimulation could potentially be used to alter genioglossal activity in awake animals. Six adult cats were instrumented for recording of EMG activity from genioglossus, abdominal musculature, and triceps. In addition, a silver ball electrode was implanted on the round window for stimulation of vestibular afferents. Subsequently, stimulation and recordings were conducted while animals were awake. In all cases, stimulation using single shocks or trains of pulses > 100 μA in intensity produced responses in all muscles, including genioglossus. The latency of the genioglossal response was approximately 12 msec, and delivering continuous current trains to the labyrinth chronically elevated the muscle's activity. Although a number of muscles were affected by the stimulus, animals experienced no obvious distress or balance disturbances. Vestibular stimulation remained effective in producing genioglossal responses until experiments were discontinued 1–2 months following onset. These data suggest that electrical vestibular stimulation could potentially be used therapeutically to alter upper airway muscle activity.

The vestibular system is known to participate in cardiovascular regulation during movement and postural alterations. The present study considered whether lesions of two regions of the posterior cerebellar vermis (the nodulus and uvula) that provide inputs to vestibular nucleus regions that affect control of blood pressure would alter cardiovascular responses during changes in posture. Blood pressure and heart rate were monitored in awake cats during nose-up tilts up to 60 degrees in amplitude before and following aspiration lesions of the nodulus or uvula; in most animals, cardiovascular responses were also recorded following the subsequent removal of vestibular inputs. Lesions of the nodulus or uvula did not affect baseline blood pressure or heart rate, although cardiovascular responses during nose-up tilts were altered. Increases in heart rate that typically occurred during 60 degrees nose-up tilt were attenuated in all three animals with lesions affecting both dorsal and ventral portions of the uvula; in contrast, the heart rate responses were augmented in the two animals with lesions mainly confined to the nodulus. Furthermore, following subsequent removal of vestibular inputs, uvulectomized animals, but not those with nodulus lesions, experienced more severe orthostatic hypotension than has previously been reported in cerebellum-intact animals with bilateral labyrinthectomies. These data suggest that the cerebellar nodulus and uvula modulate vestibulo-cardiovascular responses, although the two regions play different roles in cardiovascular regulation.