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Dive into the research topics where Timothy E. Hullar is active.

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Featured researches published by Timothy E. Hullar.


Otolaryngology-Head and Neck Surgery | 2015

Is There a Need for Performance Measures for Cochlear Implant Centers

Peter M. Vila; Timothy E. Hullar; Craig A. Buchman; Judith E. C. Lieu

Performance measures (PMs), or quality indicators, are metrics based on objective data that allow one to assess whether a system achieves a prespecified goal. Given the relatively high level of resource utilization and potential morbidity associated with cochlear implantation (CI), PMs could be used to evaluate quality of care provided by implant centers and, ultimately, optimize care delivery. This article discusses PMs currently in use, how PMs are developed, potential downsides of using PMs, and various examples of PMs that could be used in CI centers.


Archives of Otolaryngology-head & Neck Surgery | 2017

Prevalence of Semicircular Canal Hypoplasia in Patients With CHARGE Syndrome: 3C Syndrome.

Andre Wineland; Maithilee D. Menezes; Joshua S. Shimony; Marwan Shinawi; Timothy E. Hullar; Keiko Hirose

Importance CHARGE syndrome refers to a syndrome involving coloboma, heart defects, atresia choanae, retardation of growth and development, genitourinary disorders, and ear anomalies. However, Verloes revised the characteristics of CHARGE syndrome in 2005 to define this syndrome more broadly. Deficiency of the semicircular canals is now a major criterion for CHARGE syndrome. Objective To characterize patients with CHARGE syndrome at our center using Verloes’ criteria and to reevaluate the nomenclature for this condition. Design, Setting, and Participants We performed a medical chart review of patients with CHARGE syndrome and reviewed their temporal bone imaging studies at a tertiary care children’s hospital affiliated with Washington University in St Louis. Two authors independently reviewed each imaging study (A.W. and K.H.). Radiologic studies, physical findings, genetic tests, and other diagnostic tests were included. Patients with no temporal bone imaging studies were excluded. Results Eighteen children were included in this study; 13 children (72%) were male, and the mean (median; range) age of patients at the time of inner ear imaging studies was 2 years (4.5 years; 8 months to 8 years). Coloboma was present in 13 patients (72%) and choanal atresia in 5 (28%); semicircular canal anomalies were present in all patients. Additionally, 13 patients (72%) were diagnosed as having hindbrain anomalies, 17 (94%) as having endocrine disorders, 17 (94%) as having mediastinal organ malformations, and all as having middle or external ear abnormalities and development delay. Cleft lip and cleft palate were found in 6 of 14 patients (43%) who did not have choanal atresia. We tested 16 patients for mutations in the CHD7 gene; 10 were positive (63%) for mutations, 4 (25%) were negative, and 2 (13%) were inconclusive. Conclusions and Relevance Semicircular canal anomalies were the most consistent finding in our patients with CHARGE syndrome. Given the high prevalence of semicircular canal hypoplasia and importance of imaging for diagnosing CHARGE syndrome, we propose changing the term CHARGE syndrome to 3C syndrome to emphasize the importance of the semicircular canals and to recall the 3 major criteria for diagnosis: coloboma, choanal atresia, and semicircular canal anomaly. The nomenclature would also reference the 3 semicircular canals in each ear. This new name for CHARGE syndrome would provide a mnemonic and focus the disease on the most important clinical criteria for diagnosis.


Otolaryngology-Head and Neck Surgery | 2016

Analysis of Outcome Domains in Adult Cochlear Implantation A Systematic Review

Peter M. Vila; Timothy E. Hullar; Craig A. Buchman; Judith E. C. Lieu

Objectives To determine the breadth of outcome domains used in the reporting of adult cochlear implant surgery for the purpose of registry and quality measure development. Data Sources Systematic review of randomized controlled trials. Review Methods In consultation with a medical librarian, search strategies were constructed to identify randomized controlled trials studying adults undergoing cochlear implantation. MEDLINE, EMBASE, Scopus, CINAHL, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and the Database of Abstracts of Reviews of Effects were searched from database inception to July 2015. Studies were evaluated for level of evidence and risk of bias with the Cochrane Collaboration’s Risk of Bias Tool, and outcome domains were extracted from each study. Results Of 4473 unique citations found, 8 studies were included in this review. All 8 trials were evidence level 1B. Risk of bias was low in 2 trials and high in the other 6. Reported outcome domains included speech perception in quiet and noise, speech tracking, quality of life, timbre perception, hearing preservation, vestibular function, electrode insertion technique, functional measures, functional imaging, fitting time, and tinnitus. Conclusions An analysis of randomized controlled trials studying cochlear implantation in adults yielded a wide spectrum of outcome domains. This is the first study to comprehensively describe the breadth of outcome domains in adult cochlear implantation. Validated instruments from these domains could be considered for potential inclusion as quality measures and registry use.


Otolaryngology-Head and Neck Surgery | 2016

Developing Quality Measures for Adult Cochlear Implant Centers Preliminary Findings

Peter M. Vila; Judith E. C. Lieu; Timothy E. Hullar; Craig A. Buchman

The study objective was to develop quality measures for adult cochlear implant centers. A modified Delphi design beginning with focus groups of surgeons and audiologists was used, as adapted from the American College of Cardiology / American Heart Association method for creating quality measures. Two academic cochlear implant programs and 1 private program participated. Qualitative focus group analysis yielded 58 candidate measures. An additional 5 candidate measures were added from a systematic review of the literature. After exclusion of pediatric measures, structure measures, and process measures and discussion of details and implications of each measure, 8 measures remained as the preliminary Adult Cochlear Implant Outcome (CI-OUTCOME) Measure Set. This study provides a preliminary set of measures for evaluating the quality of adult cochlear implant centers, based on input from implant surgeons and audiologists. The next step will be to gather feedback from implant patients.


World Neurosurgery | 2018

Surgical Parameters for Minimally Invasive Trans–Eustachian Tube CSF Leak Repair: A Cadaveric Study and Literature Review

Erik C. Brown; Brandon P. Lucke-Wold; Justin S. Cetas; Aclan Dogan; Sachin Gupta; Timothy E. Hullar; Timothy L. Smith; Jeremy N. Ciporen

BACKGROUND Cerebrospinal fluid rhinorrhea from a lateral skull base defect refractory to spontaneous healing and/or conservative management is most commonly managed via open surgery. Approach for repair is dictated by location of the defect, which may require surgical exploration. The final common pathway is the eustachian tube (ET). Endoscopic ET obliteration via endonasal and lateral approaches is under development. Whereas ET anatomy has been studied, surgical landmarks have not been previously described or quantified. We aimed to define surgical parameters of specific utility to endoscopic ET obliteration. METHODS A literature review was performed of known ET anatomic parameters. Next, using a combination of endoscopic and open techniques in cadavers, we cannulated the intact ET and dissected its posterior component to define the major curvature position of the ET, defined as the genu, and quantified the relative distances through the ET lumen. The genu was targeted as a major obstacle encountered when cannulating the ET from the nasopharynx. RESULTS Among 10 ETs, we found an average distance of 23 ± 5 mm from the nasopharynx to the ET genu, distance of 24 ± 3 mm from the genu to the anterior aspect of the tympanic membrane and total ET length of 47 ± 4 mm. CONCLUSIONS Although membranous and petrous components of the ET are important to its function, the genu may be a more useful surgical landmark. Basic surgical parameters for endoscopic ET obliteration are defined.


Neurosurgical Focus | 2018

Minimally invasive endoscopic repair of refractory lateral skull base cerebrospinal fluid rhinorrhea: case report and review of the literature

Brandon P. Lucke-Wold; Erik C. Brown; Justin S. Cetas; Aclan Dogan; Sachin Gupta; Timothy E. Hullar; Timothy L. Smith; Jeremy N. Ciporen

Cerebrospinal fluid (CSF) leaks occur in approximately 10% of patients undergoing a translabyrinthine, retrosigmoid, or middle fossa approach for vestibular schwannoma resection. Cerebrospinal fluid rhinorrhea also results from trauma, neoplasms, and congenital defects. A high degree of difficulty in repair sometimes requires repetitive microsurgical revisions-a rate of 10% of cases is often cited. This can not only lead to morbidity but is also costly and burdensome to the health care system. In this case-based theoretical analysis, the authors summarize the literature regarding endoscopic endonasal techniques to obliterate the eustachian tube (ET) as well as compare endoscopic endonasal versus open approaches for repair. Given the results of their analysis, they recommend endoscopic endonasal ET obliteration (EEETO) as a first- or second-line technique for the repair of CSF rhinorrhea from a lateral skull base source refractory to spontaneous healing and CSF diversion. They present a case in which EEETO resolved refractory CSF rhinorrhea over a 10-month follow-up after CSF diversions, wound reexploration, revised packing of the ET via a lateral microscopic translabyrinthine approach, and the use of a vascularized flap had failed. They further summarize the literature regarding studies that describe various iterations of EEETO. By its minimally invasive nature, EEETO imposes less morbidity as well as less risk to the patient. It can be readily implemented into algorithms once CSF diversion (for example, lumbar drain) has failed, prior to considering open surgery for repair. Additional studies are warranted to further demonstrate the outcome and cost-saving benefits of EEETO as the data until now have been largely empirical yet very hopeful. The summaries and technical notes described in this paper may serve as a resource for those skull base teams faced with similar challenging and otherwise refractory CSF leaks from a lateral skull base source.


Laryngoscope | 2018

The contribution of cochlear implants to postural stability

Corey S. Shayman; Martina Mancini; Tyler S. Weaver; Laurie A. King; Timothy E. Hullar

To determine whether spatial auditory cues provided by cochlear implants can improve postural balance in adults with severe deafness.


Journal of Neurotrauma | 2018

Abnormal Turning and Its Association with Self-Reported Symptoms in Chronic Mild Traumatic Brain Injury

Peter C. Fino; Lucy Parrington; Merissa Walls; Emily Sippel; Timothy E. Hullar; James C. Chesnutt; Laurie A. King

Turning is common in daily activity and requires rapid, coordinated reorientation of the head, trunk, and pelvis toward the new direction of travel. Yet, turning gait has not been well explored in populations with mild traumatic brain injury (mTBI) who may alter their turning behavior according to self-perceived symptoms or motor dysfunction. The purpose of this study was to examine turning velocities and coordination in adults with chronic mTBI (>3 months post-injury and still reporting balance complaints) during a task simulating everyday ambulation. We hypothesized that individuals with chronic mTBI would reduce their angular velocity when turning and increase the variability of head-pelvis coordination compared with controls, and that the reduction in velocity and increased variability would be associated with their self-reported symptom score. Forty-two adults (14 chronic mTBI, 28 controls) completed the Neurobehavioral Symptom Inventory before walking 12 laps around a marked course containing two 45-degree turns, four 90-degree turns, and two 135-degree turns. Inertial sensors collected angular velocities of the head and pelvis. After adjusting for covariates, participants with chronic mTBI had significantly slower lap times and peak angular velocities of the pelvis (p < 0.01) compared with the control group. The peak velocity timing (PVT) between peak velocities of the head and pelvis, and the variability of that timing was significantly greater in participants with chronic mTBI (p < 0.01). Within the chronic mTBI group, somatosensory symptoms were associated with slower angular velocities of the head and pelvis (p = 0.03) and increased PVT variability (p < 0.01). The results suggest individuals with chronic mTBI with worse somatic symptoms have impaired head stabilization during turning in situations similar to everyday life. These results encourage future research on turning gait to examine the causal relationship between symptoms and daily locomotor function in adults with chronic mTBI.Abstract Turning is common in daily activity and requires rapid, coordinated reorientation of the head, trunk, and pelvis toward the new direction of travel. Yet, turning gait has not been well exp...


Gait & Posture | 2018

The effect of spatial auditory landmarks on ambulation

Adham M. Karim; Kavelin Rumalla; Laurie A. King; Timothy E. Hullar

The maintenance of balance and posture is a result of the collaborative efforts of vestibular, proprioceptive, and visual sensory inputs, but a fourth neural input, audition, may also improve balance. Here, we tested the hypothesis that auditory inputs function as environmental spatial landmarks whose effectiveness depends on sound localization ability during ambulation. Eight blindfolded normal young subjects performed the Fukuda-Unterberger test in three auditory conditions: silence, white noise played through headphones (head-referenced condition), and white noise played through a loudspeaker placed directly in front at 135 centimeters away from the ear at ear height (earth-referenced condition). For the earth-referenced condition, an additional experiment was performed where the effect of moving the speaker azimuthal position to 45, 90, 135, and 180° was tested. Subjects performed significantly better in the earth-referenced condition than in the head-referenced or silent conditions. Performance progressively decreased over the range from 0° to 135° but all subjects then improved slightly at the 180° compared to the 135° condition. These results suggest that presence of sound dramatically improves the ability to ambulate when vision is limited, but that sound sources must be located in the external environment in order to improve balance. This supports the hypothesis that they act by providing spatial landmarks against which head and body movement and orientation may be compared and corrected. Balance improvement in the azimuthal plane mirrors sensitivity to sound movement at similar positions, indicating that similar auditory mechanisms may underlie both processes. These results may help optimize the use of auditory cues to improve balance in particular patient populations.


Journal of Neurotrauma | 2017

Abnormal turning and its association with self-reported symptoms in chronic mTBI

Peter C. Fino; Lucy Parrington; Merissa Walls; Emily Sippel; Timothy E. Hullar; James C. Chesnutt; Laurie A. King

Turning is common in daily activity and requires rapid, coordinated reorientation of the head, trunk, and pelvis toward the new direction of travel. Yet, turning gait has not been well explored in populations with mild traumatic brain injury (mTBI) who may alter their turning behavior according to self-perceived symptoms or motor dysfunction. The purpose of this study was to examine turning velocities and coordination in adults with chronic mTBI (>3 months post-injury and still reporting balance complaints) during a task simulating everyday ambulation. We hypothesized that individuals with chronic mTBI would reduce their angular velocity when turning and increase the variability of head-pelvis coordination compared with controls, and that the reduction in velocity and increased variability would be associated with their self-reported symptom score. Forty-two adults (14 chronic mTBI, 28 controls) completed the Neurobehavioral Symptom Inventory before walking 12 laps around a marked course containing two 45-degree turns, four 90-degree turns, and two 135-degree turns. Inertial sensors collected angular velocities of the head and pelvis. After adjusting for covariates, participants with chronic mTBI had significantly slower lap times and peak angular velocities of the pelvis (p < 0.01) compared with the control group. The peak velocity timing (PVT) between peak velocities of the head and pelvis, and the variability of that timing was significantly greater in participants with chronic mTBI (p < 0.01). Within the chronic mTBI group, somatosensory symptoms were associated with slower angular velocities of the head and pelvis (p = 0.03) and increased PVT variability (p < 0.01). The results suggest individuals with chronic mTBI with worse somatic symptoms have impaired head stabilization during turning in situations similar to everyday life. These results encourage future research on turning gait to examine the causal relationship between symptoms and daily locomotor function in adults with chronic mTBI.Abstract Turning is common in daily activity and requires rapid, coordinated reorientation of the head, trunk, and pelvis toward the new direction of travel. Yet, turning gait has not been well exp...

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Peter M. Vila

Washington University in St. Louis

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Craig A. Buchman

Washington University in St. Louis

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