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With the remarkable advances in semiconductor processing, devices such as solar cells have fewer and fewer defects that impact their performance. Determination of the defects that currently limit the device performance, predominantly by increasing the charge carrier recombination rate, has become more challenging with standard methods like deep level transient spectroscopy. To circumvent this limitation, the photovoltaic community is attempting to use the measurement of the charge carrier recombination rates to identify the remaining defects, as this approach is intrinsically sensitive to the defects that limit the cell's/sample's performance/lifetime. This article reviews this new approach, contrasting it with the developments that have occurred with deep-level transient spectroscopy, finding several critical limitations in the current assumptions, and providing suggestions for an improved strategy.

BACKGROUND: Geographical location is known to affect health outcomes; however, evidence regarding whether location affects healthcare for persons suspected to have vestibular dysfunction is lacking. OBJECTIVE: To investigate whether location affects healthcare seeking and outcomes for adults with symptoms of vestibular pathology. METHODS: We assessed for regional disparities associated with demographics, diagnosis, chronological factors, and financial expenditures from Americans who participated in the Vestibular Disorders Association registry (N = 905, 57.4±12.5 years, 82.7% female, 94.8% White, and 8.1% Hispanic or Latino). Respondents were grouped per geographical regions defined by the United States Census Bureau. RESULTS: There were no significant between-region differences for age (p = 0.10), sex (p = 0.78), or ethnicity (p = 0.24). There were more Asian respondents in the West versus the Midwest (p = 0.05) and more Black respondents in the South versus the West (p = 0.05). The time to first seek care was shorter in the Northeast (17.3 [SD = 49.5] weeks) versus the South (42.4 [SD = 83.7] weeks), p = 0.015. The time from the first healthcare visit to receiving a final diagnosis was shorter in the Northeast (46.5 [SD = 75.4] weeks) versus the South (68.9 [SD = 89.7] weeks), p = 0.015. Compared to the Midwest, fewer respondents in the Northeast reported “no” out-of-pocket financial impact, p = 0.039. CONCLUSIONS: Geographical location affects healthcare seeking and outcomes for persons suspected to have vestibular dysfunction.

To develop an innovative community-academic partnership to advance, test and promote intimate partner violence screening and referral protocols by comparing the effect of integrating intimate partner violence advocates versus enhancing medical training in medical clinic settings serving women from vulnerable populations. Detecting intimate partner violence in healthcare settings allows for survivors to connect to safety and referral resources prior to violence escalating. Screening for intimate partner violence and connecting patients to referral resources requires creating a safe and trusting relationship between healthcare providers and patients. Developing screening and referral protocols responsive to survivors' needs requires involvement of clinic staff, survivors and community agencies that support survivors.Three phases of the project include Discovery, Implementation and Dissemination. Mixed-methodology will help in understanding current practices and effects of interventions.Actions included in each phase: Discovery: 1) nurse-led focus groups of clinic staff, providers and survivors to understand current clinic practices; 2) retrospective chart review of the number of screens performed, positive screens detected and interventions performed.1) randomization of patients to be interviewed by a trained advocate or by healthcare provider with enhanced training; and 2) assess the number of screenings and referrals performed in each arm and 3) evaluate outcomes of intervention. Dissemination through: presentations, manuscripts and policy recommendations at the institutional and regional level. This IRB-approved proposal was funded in July 2021 by an Advancing a Healthier Wisconsin grant.The partnership has improved channels of communication and understanding between diverse clinical care providers, survivors and community agency staff as they navigate the complex challenges to the development and integration of screening and referral protocols.This project will provide evidence of the most effective intimate partner violence screening and referral methodology that can be utilized in a wide variety of medical settings.

Vertical and torsional ocular misalignment can occur from mild traumatic brain injury or inner ear pathology, which may vary depending on head position. Here, we evaluate differences in a behavioral measure of binocular alignment in both upright and supine head position. Ocular perception of vertical and torsional alignment was measured using the torsional and vertical alignment nulling (TAN, VAN) task in N = 52 veterans with dizziness (N = 38 with traumatic brain injury), N = 41 civilians with vestibular schwannoma resection (UVD), and N = 33 healthy controls for both positions. The interquartile range within each group, regardless of head position, was greater for torsional compared to vertical misalignment. We use generalized estimating equations to compare average TAN (torsional) scores and VAN (vertical) scores between groups and test position. Compared to the healthy controls, TAN was significantly increased by + 0.4186° in veterans (P = 0.030) and by + 0.5747° in UVD (P = 0.010), but there was no difference with head position. For VAN, no difference was found between the three groups, but the misalignment did worsen by 0.0888° (P = 0.0070) as the head position moved from upright to supine. Head position had negligible effects on this behavioral measure of vertical and torsional binocular misalignment, and torsional misalignments were worse than controls in both veterans with dizziness and patients with vestibular nerve resection although neither reported torsional diplopia. Our data suggests that the tolerance for roll misalignment may be abnormally large in patients with dizziness. Alternatively, perceptual roll misalignments may be a manifest cause for dizziness, and therefore a useful proxy for distinguishing differences in putative otolith function in veterans with dizziness.

Crossing the blood–brain barrier is a crucial, rate-limiting step of brain metastasis. Understanding of the mechanisms of cancer cell extravasation from brain microcapillaries is limited as the underlying cellular and molecular processes cannot be adequately investigated using in vitro models and endpoint in vivo experiments. Using ultrastructural and functional imaging, we demonstrate that dynamic changes of activated brain microcapillaries promote the mandatory first steps of brain colonization. Successful extravasation of arrested cancer cells occurred when adjacent capillary endothelial cells (EC) entered into a distinct remodeling process. After extravasation, capillary loops were formed, which was characteristic of aggressive metastatic growth. Upon cancer cell arrest in brain microcapillaries, matrix-metalloprotease 9 (MMP9) was expressed. Inhibition of MMP2/9 and genetic perturbation of MMP9 in cancer cells, but not the host, reduced EC projections, extravasation, and brain metastasis outgrowth. These findings establish an active role of ECs in the process of cancer cell extravasation, facilitated by cross-talk between the two cell types. This extends our understanding of how host cells can contribute to brain metastasis formation and how to prevent it.Significance:Tracking single extravasating cancer cells using multimodal correlative microscopy uncovers a brain seeding mechanism involving endothelial remodeling driven by cancer cell–derived MMP9, which might enable the development of approaches to prevent brain metastasis.See related commentary by McCarty, p. 1167

Supplementary Figures and Figure legends, Supplementary Video legends and supplementary materials and methods

A variant of benign paroxysmal positional vertigo (BPPV) involves the subjective report of vertigo without the coinciding nystagmus. This presentation includes truncal retropulsion when sitting up from the ipsilesional provocative test (ie, Dix-Hallpike), which we term type 2 BPPV. The primary objective of this study is to prospectively determine the prevalence and describe the clinical course of type 2 BPPV. We offer a theoretical explanation for the absence of nystagmus.Prospective, observational study carried out in 2 tertiary hospitals. One hundred eighty patients (134 women, 46 men) met the inclusion criteria and were included between January 10, 2018, and October 30, 2019. Efficacy of physical therapy maneuvers was determined at 1-week follow-up. Three-dimensional reconstructions of the planes of the semicircular canal cupula from histological preparations are offered as evidence for the theoretical explanation.One-third of the patients met the criteria for type 2 BPPV; the remainder had typical posterior or horizontal semicircular canal involvement. Symptoms from type 2 BPPV were longer in duration yet responded favorably to physical therapy maneuvers. Upon repeat testing, 19 patients treated for posterior canalithiasis developed a slight, persistent positional downbeat nystagmus in the Dix-Hallpike position that we propose as evidence the otoconia entered the short arm of the posterior semicircular canal.Our data and 3-dimensional rendering suggest the report of vertigo, yet absent nystagmus in type 2 BPPV is from otoconia aligning with the gravitoinertial vector during provocative testing that precludes cupular stimulation. Type 2 BPPV appears to be a common and treatable form of vertigo.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1 available at: http://links.lww.com/JNPT/A372).

In this article, the impact of different hydrogen configurations and their evolution on the extent and kinetics of light- and elevated-temperature-induced degradation (LeTID) is investigated in float-zone silicon via charge carrier lifetime measurements, low-temperature Fourier-transform infrared spectroscopy, and four-point-probe resistance measurements. Degradation conditions were light soaking at 77 °C and 1 sun-equivalent illumination intensity and dark anneal at 175 °C. The initial configuration of hydrogen is manipulated by varying the wafer thickness, the cooling ramp of the fast-firing process, and the dopant type (B- or P-doped). We find lower hydrogen concentrations in thinner samples and samples with a slower cooling ramp. This suggests that hydrogen diffuses out of the sample during the cool-down, which strongly affects the final concentration of hydrogen molecules H 2 , and to a smaller degree the concentration of boron-hydrogen (BH) pairs. A regeneration of potential LeTID defects and a presumed LeTID degradation during dark annealing is found in n-type Si. In p-type Si, the LeTID extent was found to scale with H 2 , suggesting a direct link between both. The temporal evolution of BH pairs, LeTID degradation/regeneration, and surface degradation depends on wafer thickness and the cooling ramp of the fast-firing process. Based upon these findings, we formulate a theory of the hydrogen-related mechanism behind LeTID: Hydrogen originating from H 2 moves between different temporary traps. First, hydrogen binds to LeTID precursors and acceptor atoms in the silicon bulk, later moving toward the surface. This leads first to the LeTID degradation and regeneration and then to the degradation of surface passivation.

Crossing the blood–brain barrier is a crucial, rate-limiting step of brain metastasis. Understanding of the mechanisms of cancer cell extravasation from brain microcapillaries is limited as the underlying cellular and molecular processes cannot be adequately investigated using in vitro models and endpoint in vivo experiments. Using ultrastructural and functional imaging, we demonstrate that dynamic changes of activated brain microcapillaries promote the mandatory first steps of brain colonization. Successful extravasation of arrested cancer cells occurred when adjacent capillary endothelial cells (EC) entered into a distinct remodeling process. After extravasation, capillary loops were formed, which was characteristic of aggressive metastatic growth. Upon cancer cell arrest in brain microcapillaries, matrix-metalloprotease 9 (MMP9) was expressed. Inhibition of MMP2/9 and genetic perturbation of MMP9 in cancer cells, but not the host, reduced EC projections, extravasation, and brain metastasis outgrowth. These findings establish an active role of ECs in the process of cancer cell extravasation, facilitated by cross-talk between the two cell types. This extends our understanding of how host cells can contribute to brain metastasis formation and how to prevent it. Significance: Tracking single extravasating cancer cells using multimodal correlative microscopy uncovers a brain seeding mechanism involving endothelial remodeling driven by cancer cell–derived MMP9, which might enable the development of approaches to prevent brain metastasis. See related commentary by McCarty, p. 1167

Background Balance stabilization exercises are often prescribed to facilitate compensation in individuals with vestibular schwannoma (VS). However, both the assessment and prescription of these exercises are reliant on clinical observations and expert opinion rather than on quantitative evidence. The aim of this study was to quantify head motion kinematics in individuals with vestibular loss while they performed commonly prescribed balance stability exercises. Methods Using inertial measurement units, head movements of individuals with vestibular schwannoma were measured before and after surgical deafferentation and compared with age-matched controls. Results We found that individuals with vestibular schwannoma experienced more variable head motion compared to healthy controls both pre- and postoperatively, particularly in absence of visual input, but that there was little difference between preoperative and postoperative kinematic measurements for our vestibular schwannoma group. We further found correlations between head motion kinematic measures during balance exercises, performed in the absence of visual input, and multiple clinical measurements for preoperative VS subjects. Subjects with higher head motion variability also had worse DVA scores, moved more slowly during the Timed up and Go and gait speed tests, and had lower scores on the functional gait assessment. In contrast, we did not find strong correlations between clinical measures and postoperative head kinematics for the same VS subjects. Conclusions Our data suggest that further development of such metrics based on the quantification of head motion has merit for the assessment and prescription of balance exercises, as demonstrated by the calculation of a “kinematic score” for identifying the most informative balance exercise (i.e., “Standing on foam eyes closed”).

Objective To examine the effectiveness of event notification service (ENS) alerts on health care delivery processes and outcomes for older adults. Materials and methods We deployed ENS alerts in 2 Veterans Affairs (VA) medical centers using regional health information exchange (HIE) networks from March 2016 to December 2019. Alerts targeted VA-based primary care teams when older patients (aged 65+ years) were hospitalized or attended emergency departments (ED) outside the VA system. We employed a concurrent cohort study to compare postdischarge outcomes between patients whose providers received ENS alerts and those that did not (usual care). Outcome measures included: timely follow-up postdischarge (actual phone call within 7 days or an in-person primary care visit within 30 days) and all-cause inpatient or ED readmission within 30 days. Generalized linear mixed models, accounting for clustering by primary care team, were used to compare outcomes between groups. Results Compared to usual care, veterans whose primary care team received notification of non-VA acute care encounters were 4 times more likely to have phone contact within 7 days (AOR = 4.10, P Discussion ENS was associated with increased timely follow-up following non-VA acute care events, but there was no associated change in 30-day readmission rates. Optimization of ENS processes may be required to scale use and impact across health systems. Conclusion Given the importance of ENS to the VA and other health systems, this study provides guidance for future research on ENS for improving care coordination and population outcomes. Trial Registration ClinicalTrials.gov NCT02689076. “Regional Data Exchange to Improve Care for Veterans After Non-VA Hospitalization.” Registered February 23, 2016.

Impacting 1 in 4 children in the United States, childhood exposure to domestic violence predicts myriad negative sequelae. Intervening post exposure is critical to help children and their protective parent heal and avoid long-term negative consequences. Children aged 2-17 and their mothers who were victims of domestic violence participated in a 12-week group program delivered by domestic violence agency staff that provides psychoeducation on the impact of trauma and domestic violence and aims to improve parent and child well-being. The impact of the Child Witness to Domestic Violence (CWDV) program was tested in an intervention group ( n = 69 children, 33 mothers) who participated in CWDV and control group ( n = 80 children, 39 mothers) consisting of children whose mothers received adult-focused domestic violence services but were not enrolled in CWDV or other child-focused services. Multiple regression analyses controlling for child gender, child age, mother’s age, and the outcome of interest at time 1 found that participation in CWDV program significantly predicted better child functioning as indicated by less hyperactivity ( B = –.85, p = .06), fewer negative emotional symptoms ( B = –1.14, p = .01), and fewer total behavioral difficulties ( B = –2.48, p = .02) as well as higher maternal hope ( B = .57, p = .03). These data provide promising evidence of the impact of a brief, replicable group intervention that promotes healing and well-being among children and parents exposed to domestic violence. Limitations include a quasi-experimental design and reliance on maternal report.

Diffuse gliomas are primary brain tumors associated with a poor prognosis. Cellular and molecular mechanisms driving the invasive growth patterns and therapeutic resistance are incompletely understood. The emerging field of cancer neuroscience offers a novel approach to study these brain tumors in the context of their intricate interactions with the nervous system employing and combining methodological toolsets from neuroscience and oncology. Increasing evidence has shown how neurodevelopmental and neuronal-like mechanisms are hijacked leading to the discovery of multicellular brain tumor networks. Here, we review how gap junction-coupled tumor-tumor-astrocyte networks, as well as synaptic and paracrine neuron-tumor networks drive glioma progression. Molecular mechanisms of these malignant, homo- and heterotypic networks, and their complex interplay are reviewed. Lastly, potential clinical-translational implications and resulting therapeutic strategies are discussed.

By utilizing the quadratic dependency of the interferometry phase on time, the Hannover Very Long Baseline Atom Interferometer facility (VLBAI) aims for sub nm/s$^2$ gravity measurement sensitivity. With its 10 m vertical baseline, VLBAI offers promising prospects in testing fundamental physics at the interface between quantum mechanics and general relativity. Here we discuss the challenges imposed on controlling VLBAI's magnetic and gravitational environment and report on their effect on the device's accuracy. Within the inner 8 m of the magnetic shield, residual magnetic field gradients expect to cause a bias acceleration of only 6$\times$10$^{-14}$ m/s$^2$ while we evaluate the bias shift due to the facility's non-linear gravity gradient to 2.6 nm/s$^2$. The model allows the VLBAI facility to be a reference to other mobile devices for calibration purposes with an uncertainty below the 10 nm/s$^2$ level., Presented at the Ninth Meeting on CPT and Lorentz Symmetry, Bloomington, Indiana, May 17-26, 2022

Background People with multiple sclerosis (PwMS) frequently experience dizziness and imbalance that may be caused by central vestibular system dysfunction. Vestibular rehabilitation may offer an approach for improving dysfunction in these people. Objective To test the efficacy of a gaze and postural stability (GPS) retraining intervention compared to a strength and endurance (SAE) intervention in PwMS. Methods About 41 PwMS, with complaints of dizziness or history of falls, were randomized to either the GPS or SAE groups. Following randomization participants completed 6-weeks of 3×/week progressive training, delivered one-on-one by a provider. Following intervention, testing was performed at the primary (6-weeks) and secondary time point (10-weeks). A restricted maximum likelihood estimation mixed effects model was used to examine changes in the primary outcome of the Dizziness Handicap Inventory (DHI) between the 2 groups at the primary and secondary time point. Similar models were used to explore secondary outcomes between groups at both timepoints. Results Thirty-five people completed the study (17 GPS; 18 SAE). The change in the DHI at the primary time point was not statistically different between the GPS and SAE groups (mean difference = 2.33 [95% CI −9.18, 12.85]). However, both groups demonstrated significant improvement from baseline to 6-weeks (GPS −8.73; SAE −7.31). Similar results were observed for secondary outcomes and at the secondary timepoint. Conclusions In this sample of PwMS with complaints of dizziness or imbalance, 6-weeks of GPS training did not result in significantly greater improvements in dizziness handicap or balance compared to 6-weeks of SAE training.

The vertical vestibuloocular reflex (VOR) in response to pitch head impulses can be optimally trained to increase in one direction using a two-dimensional (2D) visual training target with minimal effect on the horizontal VOR.We modified the incremental VOR adaptation (IVA) technique, shown to increase the horizontal VOR in patients with vestibular hypofunction, to drive vertical VOR adaptation in healthy control subjects.We measured the horizontal and vertical active (self-generated) and passive (imposed) head impulse VOR gains (eye velocity/head velocity) before and after 15 minutes of unidirectional downward IVA training. IVA training consisted of two sessions, one using a single-dot one-dimensional (1D) target, the other a grid-of-dots 2D target.The downward head impulse VOR gain significantly increased because of training by 13.3%, whereas the upward VOR gain did not change. The addition of extraretinal (2D) feedback did not result in greater adaptation, i.e., 1D and 2D gain increases were 15.5% and 10.6%, respectively. The vertical VOR gain increase resulted in a 3.2% decrease in horizontal VOR gain.This preliminary study is the first to show that physiologically relevant (high frequency) unidirectional increases in vertical VOR gain are possible with just 15 minutes of training. This study sets the basis for future clinical trials examining vertical IVA training in patients, which may provide the first practical rehabilitation treatment to functionally improve the vertical VOR.

There is a growing interest in developing comprehensive assessments that measure intimate partner violence (IPV) alongside other adverse events that correlate with IPV and compound its effects. One promising line of research in this area has focused on the impact of exposure to multiple types of victimization, i.e., polyvictimization. The purpose of this study is to examine the experience of administration of a polyvictimization tool from staff and client perspectives in order to inform future tool developments and assessment procedures. Qualitative interviews and focus groups with clients and staff from a family justice center who had experience with the assessment tool were used to identify strengths and challenges of the assessment too and inform future tool development. Findings demonstrate that an assessment tool provides the space for clients to talk about trauma and facilitate empowerment, while providing the opportunity for psychoeducation and service referrals. Concerns about the assessment tool included adverse reactions without proper framing and language, as well as shifting the emphasis from screening for adversities toward strengths, coping skills, and resilience. Implications for future measurement development and establishing best practices in polyvictimization assessment are discussed, with an emphasis on the benefits of social service agencies utilizing assessment tools.

Hippoboscids or louse flies (Diptera: Hippoboscidae) are obligate hematophages highly specialized for an ectoparasitic life in the feathers or fur of avian or mammalian hosts, respectively. As part of an existing avian monitoring program in the Dominican Republic, two cases of parasitism by louse flies in a Black-faced Grassquit (Melanospiza bicolor) and a Green Heron (Butorides virescens) were reported. In the laboratory, the flies were examined and identified as the species Ornithoctona erythrocephala. This is the first time this hippoboscid has been observed parasitizing these two bird species, and indeed the first record of it parasitizing a species of the family Thraupidae. Keywords Caribbean, Dominican Republic, ectoparasite, Hippoboscidae, Hispaniola, Ornithoctona erythrocephala Resumen Nuevos registros de especies hospederas de una mosca parásita (Diptera: Hippoboscidae) en bosques montanos de La Española • Los hipobóscidos o moscas piojo (Diptera: Hippoboscidae) son hematófagos obligados altamente especializados para una vida ectoparásita en las plumas de las aves o el pelaje de los mamíferos hospederos. Como parte de un programa de monitoreo de aves que existe en la República Dominicana, se reportaron dos casos de parasitismo por moscas piojos en Melanospiza bicolor y Butorides virescens. En el laboratorio, las moscas fueron examinadas e identificadas como la especie Ornithoctona erythrocephala. Esta es la primera vez que se observa que este hipobóscido parasita a estas dos especies de aves y, de hecho, el primer registro de que parasita una especie de la familia Thraupidae. Palabras clave Caribe, ectoparásito, Hippoboscidae, La Española, Ornithoctona erythrocephala, República Dominicana Résumé Nouvelles mentions d’espèces hôtes d’une mouche parasite (Diptera : Hippoboscidae) dans les forêts de montagne d’Hispaniola • Les hippobosques ou mouches plates (Diptera : Hippoboscidae) sont des espèces hématophages obligatoires hautement spécialisées pour une vie ectoparasitaire dans les plumes des oiseaux ou la fourrure des mammifères. Dans le cadre d’un programme de suivi de l’avifaune en République dominicaine, deux cas de parasitisme par des hippobosques ont été signalés sur un Sporophile cici (Melanospiza bicolor) et un Héron vert (Butorides virescens). En laboratoire, les mouches ont été examinées et identifiées comme appartenant à l’espèce Ornithoctona erythrocephala. C’est la première fois que cet hippobosque est observé comme parasite de ces deux espèces d’oiseaux et comme parasite d’une espèce de la famille des Thraupidae. Mots clés Caraïbes, ectoparasite, Hippoboscidae, Hispaniola, Ornithoctona erythrocephala, République dominicaine

This case demonstrates the successful identification and treatment of atypical posterior semicircular canal benign paroxysmal positional vertigo (BPPV) based on a unique presentation of positional nystagmus, the resultant nystagmus from repositioning manoeuvers, and restored function of the affected semicircular canal. This case illustrates the importance of completing a comprehensive clinical examination and the value for incorporating the video head impulse test as well as adjusting treatment based on testing and patient response when managing variant cases of BPPV.

BACKGROUND: The gain (eye-velocity/head-velocity) of the angular vestibuloocular reflex (aVOR) during head impulses can be increased while viewing near-targets and when exposed to unilateral, incremental retinal image velocity error signals. It is not clear however, whether the tonic or phasic vestibular pathways mediate these gain increases. OBJECTIVE: Determine whether a shared pathway is responsible for gain enhancement between vergence and adaptation of aVOR gain in patients with unilateral vestibular hypofunction (UVH). MATERIAL AND METHODS: 20 patients with UVH were examined for change in aVOR gain during a vergence task and after 15-minutes of ipsilesional incremental VOR adaptation (uIVA) using StableEyes (a device that controls a laser target as a function of head velocity) during horizontal passive head impulses. A 5 % aVOR gain increase was defined as the threshold for significant change. RESULTS: 11/20 patients had >5% vergence-mediated gain increase during ipsi-lesional impulses. For uIVA, 10/20 patients had >5% ipsi-lesional gain increase. There was no correlation between the vergence-mediated gain increase and gain increase after uIVA training. CONCLUSION: Vergence-enhanced and uIVA training gain increases are mediated by separate mechanisms and/or vestibular pathways (tonic/phasic). The ability to increase the aVOR gain during vergence is not prognostic for successful adaptation training.

The angular and linear vestibulo-ocular reflex responses are greater when viewing near targets to compensate for the relatively larger translation of the eyes with respect to the target. Our aim was to measure vestibular evoked myogenic potentials using a lateral ocular electrode montage (oVEMP) with a laterally applied stimulus using a mini-shaker during both far- and near-viewing (vergence) distances to determine whether vergence affects the oVEMP response as it does the semicircular canal vestibulo-ocular reflex response. Our results show that during vergence, the p1 and n1-p1 amplitude of the lateral oVEMP response increases significantly, whereas the latencies do not change significantly. We suggest that the physiological basis for this vergence-mediated amplitude increase in potentials may be the same as those already documented using transient linear head accelerations. Our data also suggest that irregular vestibular afferents are likely mediating the vergence-mediated gain increase during linear head accelerations because only irregular afferents are stimulated during short, transient 500 Hz stimuli.

Gaze stability is the ability of the eyes to fixate a stable point when the head is moving in space. Because gaze stability is impaired in peripheral vestibular loss patients, gaze stabilization exercises are often prescribed to facilitate compensation. However, both the assessment and prescription of these exercises are subjective. Accordingly, here we quantified head motion kinematics in patients with vestibular loss while they performed the standard of care gaze stability exercises, both before and after surgical deafferentation. We also correlate the head kinematic data with standard clinical outcome measures. Using inertial measurement units, we quantified head movements in patients as they transitioned through these two vestibular states characterized by different levels of peripheral damage. Comparison with age-matched healthy control subjects revealed that the same kinematic measurements were significantly abnormal in patients both pre- and post-surgery. Regardless of direction, patients took a longer time to move their heads during the exercises. Interestingly, these changes in kinematics suggest a strategy that existed preoperatively and remained symmetric after surgery although the patients then had complete unilateral vestibular loss. Further, we found that this kinematic assessment was a good predictor of clinical outcomes, and that pre-surgery clinical measures could predict post-surgery head kinematics. Thus, together, our results provide the first experimental evidence that patients show significant changes in head kinematics during gaze stability exercises, even prior to surgery. This suggests that early changes in head kinematic strategy due to significant but incomplete vestibular loss are already maladaptive as compared to controls.

BACKGROUND AND PURPOSE This was a double-blinded randomized controlled study to investigate the effects of once-daily incremental vestibulo-ocular reflex (VOR) training over 1 week in people with chronic peripheral vestibular hypofunction. METHODS A total of 24 patients with peripheral vestibular hypofunction were randomly assigned to intervention (n = 13) or control (n = 11) groups. Training consisted of either x1 (control) or incremental VOR adaptation exercises, delivered once daily for 15 minutes over 4 days in 1 week. Primary outcome: VOR gain with video-oculography. Secondary outcomes: Compensatory saccades measured using scleral search coils, dynamic visual acuity, static balance, gait, and subjective symptoms. Between-group differences were analyzed with a linear mixed-model with repeated measures. RESULTS There was a difference in the VOR gain increase between groups (P < 0.05). The incremental training group gain increased during active (13.4% ± 16.3%) and passive (12.1% ± 19.9%) head impulse testing (P < 0.02), whereas it did not for the control group (P = 0.59). The control group had reduced compensatory saccade latency (P < 0.02). Both groups had similarly improved dynamic visual acuity scores (P < 0.05). Both groups had improved dynamic gait index scores (P < 0.002); however, only the incremental group had improved scores for the 2 walks involving head oscillations at approximately 2 Hz (horizontal: P < 0.05; vertical: P < 0.02), increased gait speed (P < 0.02), and step length (P < 0.01) during normal gait, and improved total Dizziness Handicap Inventory (P < 0.05). CONCLUSIONS Our results suggest incremental VOR adaptation significantly improves gain, gait with head rotation, balance during gait, and symptoms in patients with chronic peripheral vestibular hypofunction more so than conventional x1 gaze-stabilizing exercises.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A336).

BACKGROUND: Embedded within most rapid head rotations are gaze shifts, which is an initial eye rotation to a target of interest, followed by a head rotation towards the same target. Gaze shifts are used to acquire an image that initially is outside of the participant’s current field of vision. Currently, there are no tools available that evaluate the functional relevance of a gaze shift. OBJECTIVE: The purpose of our study was to measure dynamic visual acuity (DVA) while performing a gaze shift. METHODS: Seventy-one healthy participants (42.79±16.89 years) and 34 participants with unilateral vestibular hypofunction (UVH) (54.59±20.14 years) were tested while wearing an inertial measurement unit (IMU) sensor on the head and walking on a treadmill surrounded by three monitors. We measured visual acuity during three subcomponent tests: standing (static visual acuity), while performing an active head rotation gaze shift, and an active head rotation gaze shift while walking (gsDVAw). RESULTS: While doing gsDVAw, patients with Left UVH (n = 21) had scores worse (p = 0.023) for leftward (0.0446±0.0943 LogMAR) head rotation compared with the healthy controls (–0.0075±0.0410 LogMAR). Similarly, patients with right UVH (N = 13) had worse (p = 0.025) gsDVAw for rightward head motion (0.0307±0.0481 LogMAR) compared with healthy controls (–0.0047±0.0433 LogMAR). As a whole, gsDVAw scores were worse in UVH compared to the healthy controls when we included the ipsilesional head rotation on both sides gsDVAw (0.0061±0.0421 LogMAR healthy vs. 0.03926±0.0822 LogMAR UVH, p = 0.003). Controlling for age had no effect, the gsDVAw scores of the patients were always worse (p

Background Bilateral vestibular hypofunction is associated with chronic disequilibrium, postural instability, and unsteady gait owing to failure of vestibular reflexes that stabilize the eyes, head, and body. A vestibular implant may be effective in alleviating symptoms. Methods Persons who had had ototoxic (7 participants) or idiopathic (1 participant) bilateral vestibular hypofunction for 2 to 23 years underwent unilateral implantation of a prosthesis that electrically stimulates the three semicircular canal branches of the vestibular nerve. Clinical outcomes included the score on the Bruininks-Oseretsky Test of Motor Proficiency balance subtest (range, 0 to 36, with higher scores indicating better balance), time to failure on the modified Romberg test (range, 0 to 30 seconds), score on the Dynamic Gait Index (range, 0 to 24, with higher scores indicating better gait performance), time needed to complete the Timed Up and Go test, gait speed, pure-tone auditory detection thresholds, speech discrimination scores, and quality of life. We compared participants' results at baseline (before implantation) with those at 6 months (8 participants) and at 1 year (6 participants) with the device set in its usual treatment mode (varying stimulus pulse rate and amplitude to represent rotational head motion) and in a placebo mode (holding pulse rate and amplitude constant). Results The median scores at baseline and at 6 months on the Bruininks-Oseretsky test were 17.5 and 21.0, respectively (median within-participant difference, 5.5 points; 95% confidence interval [CI], 0 to 10.0); the median times on the modified Romberg test were 3.6 seconds and 8.3 seconds (difference, 5.1; 95% CI, 1.5 to 27.6); the median scores on the Dynamic Gait Index were 12.5 and 22.5 (difference, 10.5 points; 95% CI, 1.5 to 12.0); the median times on the Timed Up and Go test were 11.0 seconds and 8.7 seconds (difference, 2.3; 95% CI, -1.7 to 5.0); and the median speeds on the gait-speed test were 1.03 m per second and 1.10 m per second (difference, 0.13; 95% CI, -0.25 to 0.30). Placebo-mode testing confirmed that improvements were due to treatment-mode stimulation. Among the 6 participants who were also assessed at 1 year, the median within-participant changes from baseline to 1 year were generally consistent with results at 6 months. Implantation caused ipsilateral hearing loss, with the air-conducted pure-tone average detection threshold at 6 months increasing by 3 to 16 dB in 5 participants and by 74 to 104 dB in 3 participants. Changes in participant-reported disability and quality of life paralleled changes in posture and gait. Conclusions Six months and 1 year after unilateral implantation of a vestibular prosthesis for bilateral vestibular hypofunction, measures of posture, gait, and quality of life were generally in the direction of improvement from baseline, but hearing was reduced in the ear with the implant in all but 1 participant. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT02725463.).

As the Department of Veterans Affairs (VA) healthcare system seeks to expand access to comprehensive geriatric assessments, evidence-based models of care are needed to support community-dwelling older persons. We evaluated the VA Geriatric Resources for Assessment and Care of Elders (VA-GRACE) program's effect on mortality and readmissions, as well as patient, caregiver, and staff satisfaction.This retrospective cohort included patients admitted to the Richard L. Roudebush VA hospital (2010-2019) who received VA-GRACE services post-discharge and usual care controls who were potentially eligible for VA-GRACE but did not receive services. The VA-GRACE program provided home-based comprehensive, multi-disciplinary geriatrics assessment, and ongoing care. Primary outcomes included 90-day and 1-year all-cause readmissions and mortality, and patient, caregiver, and staff satisfaction. We used propensity score modeling with overlapping weighting to adjust for differences in characteristics between groups.VA-GRACE patients (N = 683) were older than controls (N = 4313) (mean age 78.3 ± 8.2 standard deviation vs. 72.2 ± 6.9 years; p 0.001) and had greater comorbidity (median Charlson Comorbidity Index 3 vs. 0; p 0.001). VA-GRACE patients had higher 90-day readmissions (adjusted odds ratio [aOR] 1.55 [95%CI 1.01-2.38]) and higher 1-year readmissions (aOR 1.74 [95%CI 1.22-2.48]). However, VA-GRACE patients had lower 90-day mortality (aOR 0.31 [95%CI 0.11-0.92]), but no statistically significant difference in 1-year mortality was observed (aOR 0.88 [95%CI 0.55-1.41]). Patients and caregivers reported that VA-GRACE home visits reduced travel burden and the program linked Veterans and caregivers to needed resources. Primary care providers reported that the VA-GRACE team helped to reduce their workload, improved medication management for their patients, and provided a view into patients' daily living situation.The VA-GRACE program provides comprehensive geriatric assessments and care to high-risk, community-dwelling older persons with high rates of satisfaction from patients, caregivers, and providers. Widespread deployment of programs like VA-GRACE will be required to support Veterans aging in place.