Browsing by Author "Otolaryngology -- Head and Neck Surgery, School of Medicine"
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Item 12 guiding premises of pediatric cochlear implant habilitation(ScienceDirect, 2018-02-28) Robbins, Amy McConkey; Otolaryngology -- Head and Neck Surgery, School of MedicineItem 3D mouse embryonic stem cell culture for generating inner ear organoids(Springer Nature, 2014) Koehler, Karl R.; Hashino, Eri; Otolaryngology -- Head and Neck Surgery, School of MedicineThis protocol describes a culture system in which inner-ear sensory tissue is produced from mouse embryonic stem (ES) cells under chemically defined conditions. This model is amenable to basic and translational investigations into inner ear biology and regeneration. In this protocol, mouse ES cells are aggregated in 96-well plates in medium containing extracellular matrix proteins to promote epithelialization. During the first 14 d, a series of precisely timed protein and small-molecule treatments sequentially induce epithelia that represent the mouse embryonic non-neural ectoderm, preplacodal ectoderm and otic vesicle epithelia. Ultimately, these tissues develop into cysts with a pseudostratified epithelium containing inner ear hair cells and supporting cells after 16-20 d. Concurrently, sensory-like neurons generate synapse-like structures with the derived hair cells. We have designated the stem cell-derived epithelia harboring hair cells, supporting cells and sensory-like neurons as inner ear organoids. This method provides a reproducible and scalable means to generate inner ear sensory tissue in vitro.Item 3D printing in surgical simulation: emphasized importance in the COVID-19 pandemic era(Future Medicine, 2021-03-01) Michaels, Ross; Witsberger, Chelsey A; Powell, Allison R; Koka, Krishna; Cohen, Katheryn; Nourmohammadi, Zahra; Green, Glen E; Zopf, David A; Otolaryngology -- Head and Neck Surgery, School of MedicineHistorically, surgical training was an apprenticeship model of see one, do one, teach one. However, a proficiency-based training approach has become increasingly implemented for assessing surgical skills with performance scores used as benchmarks to track trainee proficiency [1]. Surgical simulators are starting to be utilized more to assess proficiency in trainees on certain procedures with many residency programs having simulation as a piece of their training curriculum. Today, simulation in surgical training takes many forms. Live animals and cadavers are often implemented since these simulators can simulate operating on realistic tissue and on human anatomy respectively. There are also basic simulators that are models that simulate a component of an operation such as suturing or knot-tying. These help trainees practice certain surgical skills necessary for completing a procedure. Some of these simulators have become more complex and simulate several steps or even an entire procedure such as joint replacements and fixating fractures [1]. With the increased availability in 3D printing technology and a push toward personalized medicine, 3D printing research has exponentially increased in recent years and has been an area of investigation for the development of surgical simulators [2]. Using a 3D printer to construct models for simulation leads to vast opportunity to customize the simulator while significantly reducing cost. Prior to the advent of 3D printing and additive manufacturing, computed tomography (CT) data were used to construct anatomic models using subtractive manufacturing with the first model made in 1979 [3]. Commercial 3D printers became available in the 1980s and were introduced into the medical field in 1994 [4]. Currently, 3D printing has several surgical applications including anatomic models for surgical planning, simulation and education; implants and prostheses; and surgical guides [3].Item 3D reconstruction of vocal fold dynamics with laser high‐speed videoendoscopy in children(Wiley, 2024-10-23) Patel, Rita R.; Döllinger, Michael; Semmler, Marion; Otolaryngology -- Head and Neck Surgery, School of MedicineObjective: The objective of this study is to evaluate three-dimensional vertical motion of the superior surface of the vocal folds in vivo in (a) typically developing children as a function of vocal frequency variations and (b) a child with vocal nodules. Methods: A custom developed laser endoscope coupled with high-speed videoendoscopy was used to obtain 3D parameters from 2 healthy children, one child with vocal nodules, and 23 vocally healthy adults (females = 11, males = 12). Parameters of amplitude (mm), maximum opening/closing velocity (mm/s), and mean opening/closing velocity (mm/s) were computed for the lateral and vertical vibratory motion along the anterior, middle, and posterior sections of the vocal folds were computed. Results: We provide for the first time, absolute measurements of vertical amplitude and maximum/ mean velocity during the opening and closing phases, in vivo in children. Overall, the vertical motion was larger in vocally normal children compared with the lateral motion, especially along the visible posterior section of the vocal folds and during low pitch phonation. The opening phase dynamics were consistently large along the posterior section in the child with vocal nodules. Conclusions: The study findings establish the feasibility of capturing 3D motion in a clinical setting and provide proof of concept for the application of the proposed 3D laser in the pediatric population. Future large sample size studies are needed to establish the diagnostic potential of examining the closing phase vertical motion to evaluate vibratory development in children with normal voice and investigating the opening phase vertical motion in children with nodules.Item A single-cell level comparison of human inner ear organoids with the human cochlea and vestibular organs(Cell Press, 2023) van der Valk, Wouter H.; van Beelen, Edward S. A.; Steinhart, Matthew R.; Nist-Lund, Carl; Osorio, Daniel; de Groot, John C. M. J.; Sun, Liang; van Benthem, Peter Paul G.; Koehler, Karl R.; Locher, Heiko; Otolaryngology -- Head and Neck Surgery, School of MedicineInner ear disorders are among the most common congenital abnormalities; however, current tissue culture models lack the cell type diversity to study these disorders and normal otic development. Here, we demonstrate the robustness of human pluripotent stem cell-derived inner ear organoids (IEOs) and evaluate cell type heterogeneity by single-cell transcriptomics. To validate our findings, we construct a single-cell atlas of human fetal and adult inner ear tissue. Our study identifies various cell types in the IEOs including periotic mesenchyme, type I and type II vestibular hair cells, and developing vestibular and cochlear epithelium. Many genes linked to congenital inner ear dysfunction are confirmed to be expressed in these cell types. Additional cell-cell communication analysis within IEOs and fetal tissue highlights the role of endothelial cells on the developing sensory epithelium. These findings provide insights into this organoid model and its potential applications in studying inner ear development and disorders.Item Acetylsalicylic acid suppression of the PI3K pathway as a novel medical therapy for head and neck lymphatic malformations(Elsevier, 2021) Bonilla-Velez, Juliana; Whitlock, Kathryn B.; Ganti, Sheila; Zenner, Kaitlyn; Cheng, Chi Vicky; Jensen, Dana M.; Pham, Minh-Hang M.; Mitchell, Ryan M.; Dobyns, William; Bly, Randall A.; Bennett, James T.; Dahl, John P.; Perkins, Jonathan A.; Otolaryngology -- Head and Neck Surgery, School of MedicineObjectives: Head and neck lymphatic malformations (HNLM) are caused by gain-of-function somatic mutations in PIK3CA. Acetylsalicylic acid (ASA/aspirin) is thought to limit growth in PIK3CA-mutated neoplasms through PI3K pathway suppression. We sought to determine if ASA could be beneficial for HNLM. Methods: Retrospective case series of patients (0-18 years) offered ASA (3-5 mg/kg/day) for HNLM treatment (2010-2018). Clinical and treatment characteristics, patient-reported symptom improvement, medication tolerance, compliance, and complications were recorded. Treatment response was determined by change in patient/caregiver-reported symptoms, or HNLM size [complete (resolved), partial (decreased), or stable]. Results: Fifty-three patients were offered ASA, 23 (43%) accepted (median age 10 years, IQR 6-14). Compared to patients who declined, patients receiving ASA were more likely to have extensive malformations: ex-utero intrapartum treatment procedure, bilateral malformations, oral cavity location, ≥2 invasive treatments, or tracheotomy (p < 0.05). All patients with tissue available had PIK3CA mutations (13/23). Treatment indications included oral pain/blebs (12, 52%), recurrent pain/swelling (6, 26%), or sudden/persistent swelling (5, 22%). Treatment plan was commonly one 81 mg tablet daily (19, 83%) for 3-12 months (8, 42%). Therapeutic adherence was reported by 18 patients (78%). Symptoms improved in 18 patients [78%; decreased pain (9, 39%) and swelling (8, 35%)]. Treatment resulted in partial (14, 61%) or complete response (4, 17%). Three patients developed oral bleb bleeding, which resolved with medication discontinuation. Conclusion: ASA seems to be a well-tolerated, low-risk medication for HNLM treatment. This pilot study suggests that it often improves symptoms and reduces HNLM size. Further prospective, randomized studies are warranted to comprehensively assess indications, safety, and efficacy.Item Advanced head and neck surgery training during the COVID-19 pandemic(Wiley, 2020) Givi, Babak; Moore, Michael G.; Bewley, Arnaud F.; Coffey, Charles S.; Cohen, Marc A.; Hessel, Amy C.; Jalisi, Scharukh; Kang, Steven; Newman, Jason G.; Puscas, Liana; Shindo, Maisie; Shuman, Andrew; Thakkar, Punam; Weed, Donald T.; Chalian, Ara; Otolaryngology -- Head and Neck Surgery, School of MedicineThe COVID-19 pandemic has significantly impacted medical training. Here we assess its effect on head and neck surgical education. Methods Surveys were sent to current accredited program directors and trainees to assess the impact of COVID-19 on the fellow's experience and employment search. Current fellows' operative logs were compared with those of the 2018 to 2019 graduates. Results Despite reduction in operative volume, 82% of current American Head and Neck Society fellows have reached the number of major surgical operations to support certification. When surveyed, 86% of program directors deemed their fellow ready to enter practice. The majority of fellows felt prepared to practice ablative (96%), and microvascular surgery (73%), and 57% have secured employment to follow graduation. Five (10%) had a pending job position put on hold due to the pandemic. Conclusions Despite the impact of the COVID-19 pandemic, current accredited trainees remain well-positioned to obtain proficiency and enter the work-force.Item Advanced head and neck surgery training during the COVID-19 pandemic(Wiley, 2020) Givi, Babak; Moore, Michael G.; Bewley, Arnaud F.; Coffey, Charles S.; Cohen, Marc A.; Hessel, Amy C.; Jalisi, Scharukh; Kang, Steven; Newman, Jason G.; Puscas, Liana; Shindo, Maisie; Shuman, Andrew; Thakkar, Punam; Weed, Donald T.; Chalian, Ara; Otolaryngology -- Head and Neck Surgery, School of MedicineBackground The COVID-19 pandemic has significantly impacted medical training. Here we assess its effect on head and neck surgical education. Methods Surveys were sent to current accredited program directors and trainees to assess the impact of COVID-19 on the fellow's experience and employment search. Current fellows' operative logs were compared with those of the 2018 to 2019 graduates. Results Despite reduction in operative volume, 82% of current American Head and Neck Society fellows have reached the number of major surgical operations to support certification. When surveyed, 86% of program directors deemed their fellow ready to enter practice. The majority of fellows felt prepared to practice ablative (96%), and microvascular surgery (73%), and 57% have secured employment to follow graduation. Five (10%) had a pending job position put on hold due to the pandemic. Conclusions Despite the impact of the COVID-19 pandemic, current accredited trainees remain well-positioned to obtain proficiency and enter the work-force.Item Aerosol and droplet generation from mandible and midface fixation: Surgical risk in the pandemic era(Elsevier, 2021-01) Ye, Michael J.; Sharma, Dhruv; Campiti, Vincent J.; Rubel, Kolin E.; Burgin, Sarah J.; Illing, Elisa A.; Ting, Jonathan Y.; Hong Park, Jae; Johnson, Jeffrey D.; Vernon, Dominic J.; Lee, Hui Bae; Nesemeier, B. Ryan; Shipchandler, Taha Z.; Otolaryngology -- Head and Neck Surgery, School of MedicinePurpose The COVID-19 pandemic has led to concerns over transmission risk from healthcare procedures, especially when operating in the head and neck such as during surgical repair of facial fractures. This study aims to quantify aerosol and droplet generation from mandibular and midface open fixation and measure mitigation of airborne particles by a smoke evacuating electrocautery hand piece. Materials and methods The soft tissue of the bilateral mandible and midface of two fresh frozen cadaveric specimens was infiltrated using a 0.1% fluorescein solution. Surgical fixation via oral vestibular approach was performed on each of these sites. Droplet splatter on the surgeon's chest, facemask, and up to 198.12 cm (6.5 ft) away from each surgical site was measured against a blue background under ultraviolet-A (UV-A) light. Aerosol generation was measured using an optical particle sizer. Results No visible droplet contamination was observed for any trials of mandible or midface fixation. Total aerosolized particle counts from 0.300–10.000 μm were increased compared to baseline following each use of standard electrocautery (n = 4, p < 0.001) but not with use of a suction evacuating electrocautery hand piece (n = 4, p = 0.103). Total particle counts were also increased during use of the powered drill (n = 8, p < 0.001). Conclusions Risk from visible droplets during mandible and midface fixation is low. However, significant increases in aerosolized particles were measured after electrocautery use and during powered drilling. Aerosol dispersion is significantly decreased with the use of a smoke evacuating electrocautery hand piece.Item Aerosol and droplet generation from orbital repair: Surgical risk in the pandemic era(Elsevier, 2021) Ye, Michael J.; Vadhul, Raghav B.; Sharma, Dhruv; Campiti, Vincent J.; Burgin, Sarah J.; Illing, Elisa A.; Ting, Jonathan Y.; Hong Park, Jae; Koehler, Karl R.; Lee, Hui Bae; Vernon, Dominic J.; Johnson, Jeffrey D.; Nesemeier, B. Ryan; Shipchandler, Taha Z.; Otolaryngology -- Head and Neck Surgery, School of MedicineIntroduction The highly contagious COVID-19 has resulted in millions of deaths worldwide. Physicians performing orbital procedures may be at increased risk of occupational exposure to the virus due to exposure to secretions. The goal of this study is to measure the droplet and aerosol production during repair of the inferior orbital rim and trial a smoke-evacuating electrocautery handpiece as a mitigation device. Material and methods The inferior rim of 6 cadaveric orbits was approached transconjunctivally using either standard or smoke-evacuator electrocautery and plated using a high-speed drill. Following fluorescein inoculation, droplet generation was measured by counting under ultraviolet-A (UV-A) light against a blue background. Aerosol generation from 0.300–10.000 μm was measured using an optical particle sizer. Droplet and aerosol generation was compared against retraction of the orbital soft tissue as a negative control. Results No droplets were observed following the orbital approach using electrocautery. Visible droplets were observed after plating with a high-speed drill for 3 of 6 orbits. Total aerosol generation was significantly higher than negative control following the use of standard electrocautery. Use of smoke-evacuator electrocautery was associated with significantly lower aerosol generation in 2 of 3 size groups and in total. There was no significant increase in total aerosols associated with high-speed drilling. Discussion and conclusions Droplet generation for orbital repair was present only following plating with high-speed drill. Aerosol generation during standard electrocautery was significantly reduced using a smoke-evacuating electrocautery handpiece. Aerosols were not significantly increased by high-speed drilling.