Evaluation of clinical predictors of postoperative outcomes in tegmen defect patients with and without concurrent superior semicircular canal dehiscence and cerebrospinal fluid leak.

OBJECTIVES: Tegmen and superior semicircular canal defects have been well studied, yet the factors contributing to their onset and progression are widely debated. The clinical utility of intraoperative intracranial pressure measurements has yet to be tested. This report aims to use intraoperative opening pressure and concurrent superior semicircular canal dehiscence (SSCD) to analyze factors influencing disease course and clinical outcomes in patients with tegmen dehiscence. METHODS: A retrospective analysis of 61 patients who underwent tegmen defect repair was performed. Multiple variables of interest including body mass index (BMI), presence of SSCD, presence of dural venous sinus stenosis, opening pressure, and acetazolamide therapy use were recorded. The cohort was divided into those with or without concurrent SSCD and those presenting with or without cerebrospinal fluid (CSF) leak for analysis. RESULTS: A linear relationship between opening pressure and BMI (p = 0.009) was noted; however, intraoperative opening pressure was not associated with disease outcome. Concurrent SSCD was present in 25 % of patients, while 62 % presented with CSF leak. The concurrent SSCD group exhibited higher opening pressure, higher likelihood of having dural sinus stenosis, and higher likelihood of being discharged on acetazolamide. The CSF leak group had higher likelihood of obstructive sleep apnea and persistent symptoms. CONCLUSIONS: In patients undergoing tegmen defect repair, concurrent SSCD suggests increased disease severity. The presence of preoperative CSF leak predicts persistent symptoms following repair. BMI is linearly correlated with intracranial pressure in these patients.

Cost-Effectiveness of Diffusion Weighted MRI Versus Planned Second-Look Surgery for Cholesteatoma.

OBJECTIVE: To compare the cost-effectiveness of serial non-echo planar diffusion weighted MRI (non-EP DW MRI) versus planned second look surgery following initial canal wall up tympanomastoidectomy for the treatment of cholesteatoma. METHODS: A decision-analytic model was developed. Model inputs including residual cholesteatoma rates, rates of non-EP DW MRI positivity after surgery, and health utility scores were abstracted from published literature. Cost data were derived from the 2022 Centers for Medicare and Medicaid Services fee rates. Efficacy was defined as increase in quality-adjusted life year (QALY). One- and 2-way sensitivity analyses were performed on variables of interest to probe the model. Total time horizon was 50 years with a willingness to pay (WTP) threshold set at $50 000/QALY. RESULTS: Base case analysis revealed that planned second-look surgery ($11 537, 17.30 QALY) and imaging surveillance with non-EP DWMRI ($10 439, 17.26 QALY) were both cost effective options. Incremental cost effectiveness ratio was $27 298/QALY, which is below the WTP threhshold. One-way sensitivity analyses showed that non-EP DW MRI was more cost effective than planned second-look surgery if the rate of residual disease after surgery increased to 48.3% or if the rate of positive MRI was below 45.9%. A probabilistic sensitivity analysis at WTP of $50 000/QALY found that second-look surgery was more cost-effective in 56.7% of iterations. CONCLUSION: Non-EP DW MRI surveillance is a cost-effect alternative to planned second-look surgery following primary canal wall up tympanomastoidectomy for cholesteatoma. Cholesteatoma surveillance decisions after initial canal wall up tympanomastoidectomy should be individualized. LEVEL OF EVIDENCE: V.

Prevalence of Cochlear-Facial and Other Non-Superior Semicircular Canal Third Window Dehiscence on High-Resolution Temporal Bone CT.

BACKGROUND AND PURPOSE: The radiologic prevalence of superior semicircular canal dehiscence in the asymptomatic population has been widely studied, but less is known about the rates of other forms of third window dehiscence. Per the existing literature, the radiologic prevalence of cochlear-facial nerve dehiscence, for example, exceeds that seen in histologic studies, suggesting that conventional CT is unreliable for cochlear-facial dehiscence. These studies relied on nonisometric CT acquisitions, however, and underused multiplanar reformatting techniques, leading to false-positive findings. Our purpose was to determine the rate of cochlear-facial dehiscence and other non-superior semicircular canal third window dehiscences on optimized CT in asymptomatic patients. MATERIALS AND METHODS: Sixty-four-channel temporal bone CT scans from 602 patients in emergency departments were assessed for cochlear-facial and other non-superior semicircular canal third window dehiscences by using high-resolution, multiplanar oblique reformats. Confidence intervals for dehiscence prevalence were calculated using the Newcombe 95% interval confidence method. RESULTS: Of 602 patients, 500 were asymptomatic, while 102 had an imaging indication consistent with possible third window syndrome (symptomatic). Eight asymptomatic patients (1.6%) had cochlear-facial dehiscence, while 43 (8.4%) had jugular bulb-vestibular aqueduct dehiscence. There was no statistically significant difference between the prevalence of cochlear-facial dehiscence or jugular bulb-vestibular aqueduct dehiscence in asymptomatic patients compared with symptomatic patients. Cochlear-carotid canal, cochlear-internal auditory canal, and cochlear-petrosal sinus dehiscences were not observed. CONCLUSIONS: Sixty-four-channel CT with multioblique reformatting is sensitive and specific for identifying cochlear-facial dehiscence, with rates similar to those in postmortem series. Jugular bulb-vestibular aqueduct dehiscence is a common incidental finding and is unlikely to produce third window physiology. Other non-superior semicircular canal third window dehiscences are rare in asymptomatic patients.

Pain and Pain Control With Opioid and Nonopioid Medications After Otologic Surgery.

OBJECTIVE: To prospectively analyze pain and pain medication use following otologic surgery. STUDY DESIGN: Prospective cohort study with patient reported pain logs and medication use logs. SETTING: Tertiary academic hospital.Patients: Sixty adults who underwent outpatient otologic surgeries. INTERVENTIONS: Surveys detailing postoperative pain levels, nonopioid analgesic (NOA) use, and opioid analgesic use. MAIN OUTCOME MEASURES: Self-reported pain scores, use of NOA, and use of opioid medications normalized as milligrams morphine equivalents (MME). RESULTS: Thirty-two patients had surgery via a transcanal (TC) approach, and 28 patients had surgery via a postauricular (PA) approach. TC surgery had significantly lower reported pain scores than PA surgery on both postoperative day (POD) 1 (median pain score 2.2, IQR 0-5 vs. median pain score 4.8, IQR 3.4-6.3, respectively; p = 0.0013) and at POD5 (median pain score 0, IQR 0-0 vs. median pain score 2.0, IQR 0-3, respectively; p = 0.0002). Patients also used significantly fewer opioid medications with TC approach than patients who underwent PA approach at POD1 (median total MME 0, IQR 0-5 vs. median total MME 5.0, IQR 0-15, respectively; p = 0.03) and at POD5 (median total MME 0, IQR 0-0 vs. median total MME 0, IQR 0-5, respectively; p = 0.0012). CONCLUSIONS: Surgery with a postauricular approach is associated with higher pain and opioid use following otologic surgery. Patient- and approach-specific opioid prescribing is feasible following otologic surgery.

Scoping review of cochlear implantation in Susac's syndrome.

OBJECTIVE: Scoping review of published literature to establish clinical characteristics and audiologic outcomes in patients diagnosed with Susac's Syndrome(SS) who have undergone cochlear implantation (CI). DATA SOURCES: All published studies of CI in SS and contribution of two of our own patients who have not been reported previously. METHODS: A comprehensive search of MEDLINE (via PubMed) was carried out in March 2020 using the following keywords and related entry terms: Susac's Syndrome, Cochlear Implantation. RESULTS: Our search identified a total of five case reports of CI in SS. With the addition of our two patients reported here, we analyzed characteristics and outcomes in seven patients. Mean age at implantation was 30 years old (range 19-46), with six women and one man implanted. Mean time from onset of hearing loss to implantation was 17 months (range three months to four years). Best reported postoperative speech understanding was reported via different metrics, with six of seven patients achieving open set speech scores of 90% or better, and one subject performing at 68%. Vestibular symptoms were present preoperatively in four of seven patients (57%), with vestibular testing reported in two patients, and showing vestibulopathy in one patient. No complications were reported following cochlear implantation. CONCLUSION: Cochlear implantation is a viable option for hearing rehabilitation in patients with SS, with levels of attainment of open set speech comparable to other populations of CI candidates.

Operable, Low-Cost, High-Resolution, Patient-Specific 3D Printed Temporal Bones for Surgical Simulation and Evaluation.

OBJECTIVES: Three-dimensional printed models created on a consumer level printer can be used to practice mastoidectomy and to discern mastoidectomy experience level. Current models in the literature for mastoidectomy are limited by expense or operability. The aims of this study were (1) to investigate the utility of an inexpensive model for mastoidectomy and (2) to assess whether the model can be used as an evaluation tool to discern the experience level of the surgeon performing mastoidectomy. METHODS: Three-dimensional printed temporal bone models from the CT scan of a 7-year old patient were created using a consumer-level stereolithography 3D printer for a raw material cost of $10 each. Mastoidectomy with facial recess approach was performed by 4 PGY-2 residents, 4 PGY-5 residents, and 4 attending surgeons on the models who then filled out an evaluation. The drilled models were collected and then graded in a blinded fashion by 6 attending otolaryngologists. RESULTS: Both residents and faculty felt the model was useful for training (mean score 4.7 out of 5; range: 4-5) and case preparation (mean score: 4.3; range: 3-5). Grading of the drilled models revealed significant differences between junior resident, senior resident, and attending surgeon scores (P = .012) with moderate to excellent interrater agreement (ICC = 0.882). CONCLUSION: The described operable model that is patient-specific was rated favorably for pediatric mastoidectomy case preparation and training by residents and faculty. The model may be used to differentiate between experience levels and has promise for use in formative and summative evaluations.

Integration of vestibular and hindlimb inputs by vestibular nucleus neurons: multisensory influences on postural control.

We recently demonstrated in decerebrate and conscious cat preparations that hindlimb somatosensory inputs converge with vestibular afferent input onto neurons in multiple central nervous system (CNS) locations that participate in balance control. Although it is known that head position and limb state modulate postural reflexes, presumably through vestibulospinal and reticulospinal pathways, the combined influence of the two inputs on the activity of neurons in these brainstem regions is unknown. In the present study, we evaluated the responses of vestibular nucleus (VN) neurons to vestibular and hindlimb stimuli delivered separately and together in conscious cats. We hypothesized that VN neuronal firing during activation of vestibular and limb proprioceptive inputs would be well fit by an additive model. Extracellular single-unit recordings were obtained from VN neurons. Sinusoidal whole body rotation in the roll plane was used as the search stimulus. Units responding to the search stimulus were tested for their responses to 10° ramp-and-hold roll body rotation, 60° extension hindlimb movement, and both movements delivered simultaneously. Composite response histograms were fit by a model of low- and high-pass filtered limb and body position signals using least squares nonlinear regression. We found that VN neuronal activity during combined vestibular and hindlimb proprioceptive stimulation in the conscious cat is well fit by a simple additive model for signals with similar temporal dynamics. The mean R2 value for goodness of fit across all units was 0.74 ± 0.17. It is likely that VN neurons that exhibit these integrative properties participate in adjusting vestibulospinal outflow in response to limb state.NEW & NOTEWORTHY Vestibular nucleus neurons receive convergent information from hindlimb somatosensory inputs and vestibular inputs. In this study, extracellular single-unit recordings of vestibular nucleus neurons during conditions of passively applied limb movement, passive whole body rotations, and combined stimulation were well fit by an additive model. The integration of hindlimb somatosensory inputs with vestibular inputs at the first stage of vestibular processing suggests that vestibular nucleus neurons account for limb position in determining vestibulospinal responses to postural perturbations.

Cochlear Implant Performance in Adult Patients with Absent Intraoperative Electrically Evoked Compound Action Potentials.

OBJECTIVE: To describe cochlear implant performance outcomes in adult patients in whom no intraoperative electrically evoked compound action potential (ECAP) responses were able to be obtained despite intracochlear electrode placement. STUDY DESIGN: Retrospective case review. SETTING: Academic tertiary center. SUBJECTS AND METHODS: Patients 18 years of age and older undergoing cochlear implantation between May 2010 and September 2018 with absent ECAP measurements intraoperatively with intracochlear electrode positioning were identified. Patient performance on sentence recognition testing using the Hearing in Noise Test (HINT) and AzBio at 6 to 12 months postoperatively was compared to preimplantation scores. Additional collected data included patient demographics, etiology of hearing loss, and preoperative pure-tone average (PTA) and word recognition scores (WRSs). RESULTS: Intraoperative ECAP measurements were unable to be obtained in 15 cochlear implants performed on 14 patients out of 383 cochlear implant cases. Of the patients with absent ECAP measures, the mean ± SD age was 61.7 ± 15.7 years. Causes of hearing loss included congenital hearing loss, meningitis, autoimmune inner ear disease, otosclerosis, presbycusis, and Ménière's disease. The average preoperative PTA was 103.5 ± 17.0 dB. Twelve implanted ears had a WRS of 0% and 9 had a HINT score of 0% prior to surgery. The mean HINT score at 6 to 12 months postimplantation was 57.8% ± 37.8% and had improved by 42.6% ± 35.6% compared to the mean preimplantation HINT score (95% confidence interval, 22.0%-63.1%, P = .001, paired Student t test). CONCLUSION: There is a wide range of cochlear implant performance in patients with absent intraoperative ECAP measures ranging from sound awareness to HINT scores of 100%.

Responses of neurons in the rostral ventrolateral medulla of conscious cats to anticipated and passive movements.

The vestibular system contributes to regulating sympathetic nerve activity and blood pressure. Initial studies in decerebrate animals showed that neurons in the rostral ventrolateral medulla (RVLM) respond to small-amplitude (<10°) rotations of the body, as in other brain areas that process vestibular signals, although such movements do not affect blood distribution in the body. However, a subsequent experiment in conscious animals showed that few RVLM neurons respond to small-amplitude movements. This study tested the hypothesis that RVLM neurons in conscious animals respond to signals from the vestibular otolith organs elicited by large-amplitude static tilts. The activity of approximately one-third of RVLM neurons whose firing rate was related to the cardiac cycle, and thus likely received baroreceptor inputs, was modulated by vestibular inputs elicited by 40° head-up tilts in conscious cats, but not during 10° sinusoidal rotations in the pitch plane that affected the activity of neurons in brain regions providing inputs to the RVLM. These data suggest the existence of brain circuitry that suppresses vestibular influences on the activity of RVLM neurons and the sympathetic nervous system unless these inputs are physiologically warranted. We also determined that RVLM neurons failed to respond to a light cue signaling the movement, suggesting that feedforward cardiovascular responses do not occur before passive movements that require cardiovascular adjustments.

Metachronous Sudden Sensorineural Hearing Loss: Patient Characteristics and Treatment Outcomes.

OBJECTIVES: Idiopathic sudden sensorineural hearing loss (ISSNHL) is a distressing condition that can significantly affect quality of life. Unilateral ISSNHL, occurring first in 1 ear and then the contralateral ear at a separate and discrete time, is a rare presentation that we refer to as metachronous ISSNHL. Our objective was to characterize the presentation of metachronous ISSNHL and report on management and hearing outcomes. STUDY DESIGN: Retrospective case series. SETTING: Otology clinic at an academic tertiary referral center. SUBJECTS AND METHODS: Patients ≥18 years old presenting with metachronous ISSNHL between April 2008 to November 2017 were identified through review of the clinic electronic medical record. Metachronous ISSNHL was defined as unilateral ISSNHL occurring in temporally discrete episodes (>6 months apart) affecting both ears. Patients with identifiable causes for sudden hearing loss were excluded. Patient demographics, comorbidities, management, and audiologic outcomes were recorded. RESULTS: Eleven patients with metachronous ISSNHL were identified out of 558 patients with ISSNHL. In patients with metachronous ISSNHL, the mean ± standard deviation age at the time of ISSNHL in the second ear was 58.6 ± 15.2 years (range, 31-77 years). The mean interval between episodes was 9.6 ± 7.5 years (range, 1-22 years). Patients were treated with systemic and intratympanic steroids with variable hearing recovery; 5 patients with resultant bilateral severe to profound hearing loss underwent successful cochlear implantation. CONCLUSION: Metachronous ISSNHL is uncommon. Treatment is similar to ISSNHL, and cochlear implantation can successfully restore hearing in individuals who do not experience recovery.

Responses of Neurons in the Medullary Lateral Tegmental Field and Nucleus Tractus Solitarius to Vestibular Stimuli in Conscious Felines.

Considerable evidence shows that the vestibular system contributes to adjusting sympathetic nervous system activity to maintain adequate blood pressure during movement and changes in posture. However, only a few prior experiments entailed recordings in conscious animals from brainstem neurons presumed to convey baroreceptor and vestibular inputs to neurons in the rostral ventrolateral medulla (RVLM) that provide inputs to sympathetic preganglionic neurons in the spinal cord. In this study, recordings were made in conscious felines from neurons in the medullary lateral tegmental field (LTF) and nucleus tractus solitarius (NTS) identified as regulating sympathetic nervous system activity by exhibiting changes in firing rate related to the cardiac cycle, or cardiac-related activity (CRA). Approximately 38% of LTF and NTS neurons responded to static 40° head up tilts with a change in firing rate (increase for 60% of the neurons, decrease for 40%) of ~50%. However, few of these neurons responded to 10° sinusoidal rotations in the pitch plane, in contrast to prior findings in decerebrate animals that the firing rates of both NTS and LTF neurons are modulated by small-amplitude body rotations. Thus, as previously demonstrated for RVLM neurons, in conscious animals NTS and LTF neurons only respond to large rotations that lead to changes in sympathetic nervous system activity. The similar responses to head-up rotations of LTF and NTS neurons with those documented for RVLM neurons suggest that LTF and NTS neurons are components of the vestibulo-sympathetic reflex pathway. However, a difference between NTS/LTF and RVLM neurons was variability in CRA over time. This variability was significantly greater for RVLM neurons, raising the hypothesis that the responsiveness of these neurons to baroreceptor input is adjusted based on the animal's vigilance and alertness.

Comparison of Spontaneous Temporal Bone Cerebrospinal Fluid Leaks From the Middle and Posterior Fossa.

OBJECTIVES: To compare patients surgically managed for spontaneous cerebrospinal fluid (CSF) leaks of the temporal bone arising from the middle cranial fossa (MCF) and posterior cranial fossa (PCF) and to describe the surgical management of posterior fossa CSF leaks. STUDY DESIGN: Retrospective case review. SETTING: Academic tertiary center. PATIENTS: Adult patients presenting with spontaneous temporal bone CSF leaks undergoing operative repair between January 2010 and August 2018. Patients with a history of trauma, previous mastoid surgery, and iatrogenic CSF leaks were excluded. INTERVENTION: Transmastoid or MCF CSF leak repair. MAIN OUTCOME MEASURES: Patient demographics, body mass index (BMI), comorbidities, presenting features, and lumbar puncture opening pressures were compared between groups and the management of the PCF CSF leaks described. RESULTS: Forty-six patients (26 women, 20 men) were included. The mean age at the time of repair was 58.0 ±â€Š12.9 years (±SD). The origin of the CSF leak was from the PCF in three patients and MCF in 43 patients. All three patients with PCF leaks presented with an acute history of meningitis compared with only seven (16%) in the MCF group. This difference was statistically significant (p = 0.01, Fisher's exact test). There were no statistically significant differences in age, sex, BMI, or lumbar puncture opening pressures. The PCF leaks were repaired using a transmastoid approach with multilayer closure of the bony defect and fat graft obliteration of the mastoid. CONCLUSIONS: Spontaneous CSF leaks arising from the PCF are rare and may present more commonly with meningitis. Identification requires careful review of imaging.

Optimization of Intraoperative Imaging Protocol to Confirm Placement of Cochlear Implant Electrodes.

OBJECTIVES: The need to intraoperatively confirm correct placement of the active electrode of a cochlear implant may occur in various clinical settings. These include a malformed cochlea, difficulty with insertion, or suboptimal or abnormal electrical responses (impedance or evoked action potentials) obtained during intraoperative testing. Frustration with inconsistent images using portable x-ray machines prompted this study to determine the technique needed to reliably image the electrode within the cochlea. Our objective was to establish a radiology protocol that would be reproducible and reliable across institutions. METHODS: Prospective cadaveric imaging study. Access to the round window via the facial recess was established using cadaver heads. Electrodes provided by three cochlear implant manufacturers were inserted into the cochlea. The position of the head, angle of the x-ray tube, and beam settings were varied. A compendium of electrode images was obtained and analyzed by neurotologists and a head and neck radiologist to reach a consensus on an optimal imaging protocol. RESULTS: The optimal position for intraoperative x-ray confirmation of cochlear implant electrode placement is obtained by turning the head 45 degrees toward the contralateral ear. The portable digital x-ray machine and central ray was angled 15 degrees (aiming cephalic) from vertical with exposure settings of 32 mAs at 70 kVp and the digital radiography image receptor was positioned under the mattress of the operating table. CONCLUSION: A protocol for patient and beam source positioning and exposure using a portable digital x-ray unit can provide reliable imaging for intraoperative confirmation of cochlear implant electrode positioning.

Evaluation of 3D Printed Temporal Bone Models in Preparation for Middle Cranial Fossa Surgery.

HYPOTHESIS: Patient-specific 3D printed models are useful presurgical planning tools because they accurately represent the anatomy and drilling characteristics of the middle cranial fossa (MCF) approach to the internal auditory canal (IAC). BACKGROUND: The MCF approach to the IAC can be challenging due to variability of the bony architecture along the floor of the middle fossa. Patient-specific 3D printed models may enhance surgeon knowledge of a given patient's anatomy when preparing for MCF surgery. METHODS: Six temporal bone models were printed from photoacrylic resin based on CT data obtained from cadaveric specimens using a desktop stereolithography 3D printer. Critical structures to avoid injuring, the facial nerve and membranous labyrinth, were modeled as hollow cavities and filled with indicator paint. Two neurotologists each drilled three 3D printed models and the corresponding cadaveric specimens, and then completed a 41-item visual analog scale questionnaire (score range of each item: 0-10) to assess the model's accuracy, utility, and potential as a training tool. RESULTS: Drilling the model was favorably rated (median score 9.2; range 7.3-9.6) for its ability to provide surgeons with an accurate mental image of the corresponding cadaveric anatomy. Overall similarity of feel of drilling the model in comparison to human bone was moderate (median 7.6; range 6.6-9.0). Surgeons would use this model to prepare for future cases (median 9.4; range 5.1-9.9) and felt it had excellent utility for training purposes (median 9.3; range 8.4-9.9). CONCLUSIONS: Patient-specific 3D printed models provide an anatomically accurate and favorable tool for preparing for MCF surgery.

Patient Positioning During In-Office Otologic Procedures Impacts Physician Ergonomics.

OBJECTIVE: The purpose of this study was to evaluate the impact of patient positioning on physician ergonomics during in-office otologic procedures. A previous simulation study suggested that placing patients supine during in-office otology procedures is ergonomically favorable. This study aims to substantiate these findings during the routine care of patients in an otolaryngology practice setting. STUDY DESIGN: Observational study. SETTING: Outpatient otology clinic within tertiary care facility. STUDY SUBJECTS: Two neurotology attending physicians. INTERVENTIONS: Physicians performed cerumen removal procedures in the office with patients either in the seated position (n = 24) or supine position (n = 24). MAIN OUTCOME MEASURES: The rapid upper limb assessment (RULA), a validated instrument that measures body positioning with a focus on the upper arm, was used to measure ergonomic positioning. RULA scores correlate occupational body positioning with a numeric representation of musculoskeletal injury risk ranging from 1 (minimal risk) to 7 (very high risk). RESULTS: Overall median RULA scores were 4.5 (medium risk) with patients in the seated position, and 2 (low risk) with patients in the supine position (p < 0.0001). Similarly, RULA scores were significantly lower with patients in the supine position when each physician was evaluated independently (p < 0.0001, for both). CONCLUSIONS: Placing patients in a supine position for cerumen removal results in more favorable ergonomic positioning for the physician, thus reducing risk for work-related musculoskeletal disorders. This suggests that physicians should consider placing patients in the supine position for in-office otologic procedures. Further study is needed to investigate optimal ergonomic positioning for other common otolaryngology procedures.

Imaging in the Diagnosis and Management of Necrotizing Otitis Externa: A Survey of Practice Patterns.

OBJECTIVE: To survey neurotologists and head and neck radiologists regarding use of imaging in the diagnosis and management of necrotizing otitis externa (NOE). STUDY DESIGN: Cross-sectional survey study. SETTING: Online survey distributed through email to specialty society membership lists. PARTICIPANTS: Neurotologists and head and neck radiologists with membership in either the American Neurotology Society or The American Society of Head and Neck Radiology. MAIN OUTCOME MEASURES: Responses to survey consisting of two demographic and seven clinically oriented questions related to the use of imaging in the diagnosis and management of NOE. RESULTS: One hundred thirty-six participants responded to the survey. The imaging modality of choice in establishing the diagnosis of NOE selected by the respondents was computed tomography (CT) (37.5%) followed by technetium scintigraphy (21.3%). Magnetic resonance imaging (MRI) was the preferred investigation by 41.9% of participants for determining extent of disease. Gallium scanning was the imaging modality preferred by 32.4% of respondents for determining when to cease medical therapy. Ninety-five percent of participants responded that CT scans were always or frequently used in the diagnosis and management of NOE compared with 72.8% for MRI, 34.5% for gallium scans, and 34.2% for technetium scans. CONCLUSIONS: There is considerable heterogeneity in the preferred imaging modalities used in the diagnosis and management of NOE. CT and MRI are the preferred contemporary modalities used by many physicians, demonstrating a shift away from the historic use of nuclear medicine scans.

Cardiovascular adjustments during anticipated postural changes.

It is well-documented that feedforward cardiovascular responses occur at the onset of exercise, but it is unclear if such responses are associated with other types of movements. In this study, we tested the hypothesis that feedforward cardiovascular responses occur when a passive (imposed) 60° head-up tilt is anticipated, such that changes in heart rate and carotid artery blood flow (CBF) commence prior to the onset of the rotation. A light cue preceded head-up tilts by 10 sec, and heart rate and CBF were determined for 5-sec time periods prior to and during tilts. Even after these stimuli were provided for thousands of trials spanning several months, no systematic changes in CBF and heart rate occurred prior to tilts, and variability in cardiovascular adjustments during tilt remained substantial over time. We also hypothesized that substitution of 20° for 60° tilts in a subset of trials would result in exaggerated cardiovascular responses (as animals expected 60° tilts), which were not observed. These data suggest that cardiovascular adjustments during passive changes in posture are mainly elicited by feedback mechanisms, and that anticipation of passive head-up tilts does not diminish the likelihood that a decrease in carotid blood flow will occur during the movements.

Hearing Preservation: Does Electrode Choice Matter?

Objective Evaluate if electrode design affects hearing preservation (HP) following cochlear implantation (CI) with full-length electrodes. Study Design Case series with chart review. Setting Tertiary referral academic center. Subjects and Methods Forty-five adults with low-frequency hearing (≤85 dB at 250 and 500 Hz) who underwent unilateral CI with full-length electrode arrays made by 1 manufacturer were included. HP was calculated with (1) mean low-frequency pure-tone average (LFPTA) at 250 and 500 Hz (MEAN method), (2) a percentile method across the audiometric frequency spectrum generating an S-value (HEARRING method), and (3) functional if hearing remained ≤85 dB at 250 and 500 Hz. Audiometric testing was performed approximately 1 month and 1 year postoperatively, yielding short-term and long-term results, respectively. Results Of 45 patients who underwent CI, 46.7% received lateral wall (LW) and 53.3% received perimodiolar (PM) electrodes. At short-term follow-up, LW electrodes were associated with significantly better HP than PM (LFPTA method: 27.7 vs 39.3 dB, P < .05; S-value method: 48.2 vs 21.8%, P < .05). In multivariate regression of short-term outcomes, LW electrode use was a significant predictor of better HP ( P < .05). At long-term follow-up, electrode type was not associated with HP. Younger patient age was the only significant predictor of long-term HP on multivariate analysis ( P < .05). Conclusion The LW electrode is associated with short-term HP, suggesting its design is favorable for limiting trauma to the cochlea during and directly following CI. Other factors, including age, are relevant for maintaining HP over the long term. The data support further investigation into what modifiable factors may promote long-term HP.

Descending Influences on Vestibulospinal and Vestibulosympathetic Reflexes.

This review considers the integration of vestibular and other signals by the central nervous system pathways that participate in balance control and blood pressure regulation, with an emphasis on how this integration may modify posture-related responses in accordance with behavioral context. Two pathways convey vestibular signals to limb motoneurons: the lateral vestibulospinal tract and reticulospinal projections. Both pathways receive direct inputs from the cerebral cortex and cerebellum, and also integrate vestibular, spinal, and other inputs. Decerebration in animals or strokes that interrupt corticobulbar projections in humans alter the gain of vestibulospinal reflexes and the responses of vestibular nucleus neurons to particular stimuli. This evidence shows that supratentorial regions modify the activity of the vestibular system, but the functional importance of descending influences on vestibulospinal reflexes acting on the limbs is currently unknown. It is often overlooked that the vestibulospinal and reticulospinal systems mainly terminate on spinal interneurons, and not directly on motoneurons, yet little is known about the transformation of vestibular signals that occurs in the spinal cord. Unexpected changes in body position that elicit vestibulospinal reflexes can also produce vestibulosympathetic responses that serve to maintain stable blood pressure. Vestibulosympathetic reflexes are mediated, at least in part, through a specialized group of reticulospinal neurons in the rostral ventrolateral medulla that project to sympathetic preganglionic neurons in the spinal cord. However, other pathways may also contribute to these responses, including those that dually participate in motor control and regulation of sympathetic nervous system activity. Vestibulosympathetic reflexes differ in conscious and decerebrate animals, indicating that supratentorial regions alter these responses. However, as with vestibular reflexes acting on the limbs, little is known about the physiological significance of descending control of vestibulosympathetic pathways.