A Novel Three-Dimensional Robot Arm Steered Camera for Ear Surgery.

ABSTRACT: Ear surgery requires magnified imaging of anatomical structures from its beginning to achieve safe and successful surgical outcomes. The historical evolution of magnification in otology has developed from monocular to binocular, and to three-dimensional and even to digital in modern times. Current technological advancements pursue high-quality visualization for the best surgical outcomes but also ergonomic for surgeons. Here, we evaluated the usability of such new technology in common otological surgeries like cochlear implantation and stapedectomy for the first time in patients. A three-dimensional camera mounted to a robot arm has hands-free control by goggles worn by the surgeon on a head mount. The camera at a distance of the patients but can also be draped in a sterile way that it forms a barrier tent between patient and surgical personnel in the theatre. The main reason to evaluate the feasibility of this new exoscope was driven by COVID-19 obligate measures for elective surgery such as hearing restoration. This new technology can be considered an important advantage for the surgeons working in microsurgery to perform their elective operations without aerosolization of the drill rinsing water possibly containing contaminated tissue. From a subjective point of view, the image quality is equivalent to conventional microscopes to provide safe otologic surgery.

Analysis of aerosol production and aerosol dispersion during otologic surgery.

BACKGROUND: As a respiratory disease, the transmission of Coronavirus disease (COVID-19) is mainly caused by small droplets and aerosols. Healthcare personnel are particularly exposed during otologic surgery given the continuity with the nasopharynx, where the viral load is high, and the use of high-speed instruments. The purpose of the present study is to test a model of droplet dispersion produced in the performance of a drilling procedure on human bone to provide information about its distribution and size of the deposit in similar conditions to those of an operating theatre, to design different preventive measures. MATERIAL AND METHOD: A mastoidectomy and trans-labyrinthine approach were performed on an embalmed human corpse using for irrigation during drilling methylene blue dye in physiological saline solution (pss) at a concentration of 0.324 mg/mL. The distribution of the drops was stablished using semi-absorbent papers of size 52 cm × 42 cm covering the area around the dissection field to a radius of 150 cm and on the corpse at different heights to check vertical dispersion. The collected deposit material was analysed with the microscope at different magnification objectives. RESULTS: Droplets between 2 µm and 2.6 cm were obtained. The visualization of the coloured droplets in the horizontal plane at a magnification of 1.5 was detected at 150 cm from the focus of emission of milling particles. DISCUSSION: According to our study, bone drilling with high speed motors under continuous saline irrigation in a haemorrhagic surgical field increases the amount of aerosols exposing healthcare personnel to additional airbone particles. This risk does not end in the operating rooms as particles smaller than 2 µm can be suspended in the air for hours and could exit the operating theatre due to the use of positive pressure systems. Thus, the use of N95, FFP2, FFP3 or PAPRS should be considered and the development of hood systems to prevent the dispersion of aerosols during these procedures should be considered.

Feasibility study of the Vitom 3D exoscope in ENT surgery using an animal model: relevance to coronavirus disease 2019.

OBJECTIVE: The application of a 4K display resolution three-dimensional exoscope system (Vitom 3D) was evaluated to determine the feasibility of adopting the system in ENT surgery in the coronavirus disease 2019 era and beyond. METHODS: Eighteen ENT surgeons performed structured otological tasks on fresh-frozen sheep heads using the Vitom 3D. Structured feedback of the participants' experience was analysed. RESULTS: Seventy-four per cent and 94 per cent of participants reported that the Vitom 3D was ergonomic and comfortable to use respectively. Whilst colour fidelity and image quality were very good, 50 per cent of participants reported image distortion and pixilation at the highest magnification. All participants agreed that there was an increased educational value to exoscope technology. Half the participants preferred the microscope over the Vitom 3D for fine otological work, which may reflect the learning curve. CONCLUSION: The Vitom 3D exoscope is a promising and viable alternative for performing otological surgery when using full personal protective equipment in the coronavirus disease 2019 era.

Training in endoscopic ear surgery using the papaya petiole.

BACKGROUND: Endoscopic ear surgery is a game changer in the field of otology. Training in endoscopic skills is essential for ENT residents, and is especially important during the coronavirus disease 2019 lockdown period. In such difficult times, ENT residents and surgeons can undergo hands-on training using a papaya petiole, even within their homes. OBJECTIVE: Endoscopic ear surgery training can be carried out using a papaya petiole, enabling the practice of grommet insertion, tympanomeatal flap elevation and foreign body removal from the external auditory canal. This model does not need any laboratory setup. RESULTS AND CONCLUSION: The hollow structure of the papaya petiole model is very similar to that of the external auditory canal, making training in endoscopic ear surgery easy. Use of the model helps a beginner to train in endoscopic handling and microsurgical instrumentation, and improves depth perception. In addition, it does not require high-end facilities to store equipment or undertake the training at any given point in time.

Exoscope-assisted Otologic Surgery During the COVID-19 Pandemic.

OBJECTIVE: The recent COVID-19 pandemic has required careful reconsideration of safe operating room practices. We describe our initial experiences performing otologic surgery with the exoscope during the COVID-19 pandemic. METHOD: The exoscope was used for several semiurgent otologic surgeries in combination with complete eye protection, a "tent" drape, a smoke evacuator with ultra-low particulate air filter, and betadine irrigation. These techniques are demonstrated in the accompanying video. This was compared with our experiences using the microscope. RESULTS: The described modified goggles allowed complete eye protection while providing a fully three-dimensional view of the surgical site. The other safety measures described are simple and efficient techniques which can easily be adopted for otologic surgery using the microscope. CONCLUSION: Use of the exoscope for otologic surgery during the COVID-19 pandemic allows full three-dimensional visualization of the surgical field while simultaneously providing complete eye protection. Use of the "tent" drape, ultra-low particulate air filter, and betadine irrigation are also options that otologic surgeons may consider for additional safety.

Using a 4K three-dimensional exoscope system (Vitom 3D) for mastoid surgery during the coronavirus disease 2019 pandemic.

OBJECTIVE: Microscopic surgery is currently considered the 'gold standard' for middle-ear, mastoid and lateral skull base surgery. The coronavirus disease 2019 pandemic has made microscopic surgery more challenging to perform. This work aimed to demonstrate the feasibility of the Vitom 3D system, which integrates a high-definition (4K) view and three-dimensional technology for ear surgery, within the context of the pandemic. METHOD: Combined approach tympanoplasty and ossiculoplasty were performed for cholesteatoma using the Vitom 3D system exclusively. RESULTS: Surgery was performed successfully. The patient made a good recovery, with no evidence of residual disease at follow up. The compact system has excellent depth of field, magnification and colour. It enables ergonomic work, improved work flow, and is ideal for teaching and training. CONCLUSION: The Vitom 3D system is considered a revolutionary alternative to microscope-assisted surgery, particularly in light of coronavirus disease 2019. It allows delivery of safe otological surgery, which may aid in continuing elective surgery.

COVID-19 Pandemic and Otologic Surgery.

All around world, the COVID-19 pandemic is accelerating, and any insight we can learn from our colleagues who have either encountered or are currently going through this will be used to protect our patients, our medical staff, and ourselves. No one knows to the best of our understanding whether or not COVID-19 includes the respiratory mucosal lining the middle ear and mastoid air cell system-but it seems probable they do. Since the rest of the airways are affected, and so is the nose and nasopharynx, it seems possible that the lining of the Eustachian tube, middle ear and mastoid air cell system would all be polluted. Viral particle aerosolization, which can occur otologic surgery using powered instruments and they remain in the air for at least 3 hours. Powered air purifying respirators are supplied even shorter than N95 masks, but strongly believed they are important for our team safety and protection. This mini review provides fundamental knowledge on otologic surgery feasibility in the COVID-19 pandemic from an objective perspective.

Middle Ear Viral Load Considerations in the COVID-19 Era: A Systematic Review.

OBJECTIVE: To systematically review the available medical literature to investigate the viral load in the middle ear and mastoid cavity and the potential risk of exposure to airborne viruses during otologic surgery. DATA SOURCES: PubMed, MEDLINE, and Cochrane databases. STUDY SELECTION: This review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Protocol. DATA EXTRACTION: Using the Boolean method and relevant search term combinations for terms "mastoid," "middle ear," "virus," "exposure" "COVID-19" "SARS-CoV-2." PubMed, MEDLINE, and Cochrane databases were queried. A total of 57 abstracts were identified and screened by two independent reviewers. Following inclusion and exclusion criteria, 18 studies were selected for the final analysis. DATA SYNTHESIS: Due to the heterogeneity of clinical data, a meta-analysis was not feasible. RESULTS: Rhinovirus, followed by respiratory syncytial virus are reported to be the most prevalent viruses in MEF samples but formal statistical analysis is precluded by the heterogeneity of the studies. Drilling was identified to have the highest risk for aerosol generation and therefore viral exposure during otologic Surgery. CONCLUSIONS: The medical literature has consistently demonstrated the presence of nucleic acids of respiratory viruses involving the middle ear, including SARS-CoV2 in a recent postmortem study. Although no in vivo studies have been conducted, due to the likely risk of transmission, middle ear and mastoid procedures, particularly involving the use of a drill should be deferred, if possible, during the pandemic and enhanced personal protective equipment (PPE) used if surgery is necessary.

Quantification and Comparison of Droplet Formation During Endoscopic and Microscopic Ear Surgery: A Cadaveric Model.

OBJECTIVES: The COVID-19 pandemic and the disproportional spread of the disease among otorhinolaryngologists raised concerns regarding the safety of health care staff. Therefore, a quantitative risk assessment for otologic surgery would be desirable. This study aims to quantitatively compare the risk of perioperative droplet formation between microscopic and endoscopic approaches. STUDY DESIGN: Experimental research. SETTING: Temporal bone laboratory. METHODS: The middle ear of whole head specimens was injected with fluorescein (0.2 mg/10 mL) before endoscopic and microscopic epitympanectomy and mastoidectomy. Fluorescent droplet deposition on the surgical table was recorded under ultraviolet light, quantified, and compared among the interventions. Drilling time, droplet proportion, fluorescein intensity, and droplet size were assessed for every procedure. RESULTS: A total of 12 procedures were performed: 4 endoscopic epitympanectomies, 4 microscopic epitympanectomies, and 4 mastoidectomies. The mean (SD) proportion of fluorescein droplets was 0.14‰ (0.10‰) for endoscopic epitympanectomy and 0.64‰ (0.31‰) for microscopic epitympanectomy. During mastoidectomy, the deposition of droplets was 8.77‰ (6.71‰). Statistical comparison based on a mixed effects model revealed a significant increase (0.50‰) in droplet deposition during microscopic epitympanectomy as compared with endoscopic epitympanectomy (95% CI, 0.16‰ to 0.84‰). CONCLUSIONS: There is considerable droplet generation during otologic surgery, and this represents a risk for the spread of airborne infectious diseases. The endoscopic technique offers the lowest risk of droplet formation as compared with microscopic approaches, with a significant 4.5-fold reduction of droplets between endoscopic and microscopic epitympanectomy and a 62-fold reduction between endoscopic epitympanectomy and cortical mastoidectomy.

Coronavirus Disease-19 and Otology/Neurotology.

The severe acute respiratory syndrome corona virus 2, responsible for the worldwide COVID-19 pandemic, has caused unprecedented changes to society as we know it. The effects have been particularly palpable in the practice of medicine. The field of otolaryngology has not been spared. We have had to significantly alter the way we provide care to patients, changes that are likely to become a new norm for the foreseeable future. This article highlights some of the changes as they apply to otology/neurotology. Although this is written from the perspective of an academic physician, it is also applicable to private practice colleagues.

An operative barrier system for skull base and mastoid surgery: creating a safe operative theatre in the era of COVID-19.

Within Neurotology, special draping systems have been devised for mastoid surgery recognizing that drilling of middle ear mucosa is an aerosol generating medical procedure (AGMP) which can place surgical teams at risk of COVID-19 infection. We provide a thorough description of a barrier system utilized in our practice, along with work completed by our group to better quantify its effectiveness. Utilization of a barrier system can provide near complete bone dust and droplet containment within the surgical field and prevent contamination of other healthcare workers. As this is an early system, further adaptations and national collaborations are required to ultimately arrive at a system that seamlessly integrates into the surgical suite. While these barrier systems are new, they are timely as we face a pandemic, and can play a crucial role in safely resuming surgery.

Covid-19 and Otologic/Neurotologic Practices: Suggestions to Improve the Safety of Surgery and Consultations.

: Since the beginning of 2020, the world has been confronted by the Covid-19 pandemic. The lock-down aims to limit the circulation of the virus and thus avoid overwhelming healthcare systems. Healthcare workers have had to adapt by postponing consultation and surgical activities. Otolaryngologists are particularly exposed to infection from the upper airway where the virus is highly concentrated. Literature has previously reported other human coronaviruses in the middle ear and mastoid, suggesting a risk of infection to staff during ear surgery where aerosolizing procedures are usually used. The aim of this article is to propose a strategy for planning consultations and surgeries for ear and lateral skull base diseases, in the context of the current active evolution of the pandemic and of the future gradual recovery to normal practice.

COVID-19 and ear endoscopy in otologic practices.

PURPOSE: Otolaryngologists have had to postpone the majority of surgical procedures in the current COVID-19 pandemic. Airborne transmission, beyond the projection of droplets from upper airways, expose healthcare workers to a risk of viral infection. Aerosol generating procedures (AGP) increase the risk of viral transmission to staff within the operating room. METHODS: Surgery of middle ear and mastoid is also considered an AGP, particularly mastoidectomy performed using a high-speed drill. The authors report their experience in endoscopic ear surgery as an alternative technique to reduce AGP in otologic procedures. RESULTS: Transcanal endoscopic ear surgery is a reliable technique used to manage many otologic conditions. CONCLUSION: The endoscopic approach may reduce the risk of viral transmission to operating room staff by reducing the need for mastoidectomy.

Recommended Personal Protective Equipment for Cochlear Implant and Other Mastoid Surgery During the COVID-19 Era.

OBJECTIVES/HYPOTHESIS: The overall aim of this study was to evaluate personal protective equipment (PPE) that may facilitate the safe recommencement of cochlear implantation in the COVID-19 era, with the broader goal of minimizing the period of auditory deprivation in prelingually deaf children and reducing the risk of cochlear ossification in individuals following meningitis. METHODS: The study design comprised 1) an objective assessment of mastoid drilling-induced droplet spread conducted during simulated cochlear implant (CI) surgery and its mitigation via the use of a protective drape tent and 2) an evaluation of three PPE configurations by otologists while performing mastoid drilling on ex vivo temporal bones. The various PPE solutions were assessed in terms of their impact on communication, vital physiological parameters, visual acuity and fields, and acceptability to surgeons using a systematic risk-based approach. RESULTS: Droplet spread during simulated CI surgery extended over 2 m, a distance greater than previously reported. A drape tent significantly reduced droplet spread. The ensemble of a half-face mask and safety spoggles (foam lined safety goggles) had consistently superior performance across all aspects of clinical usability. All other PPE options were found to substantially restrict the visual field, making them unsafe for microsurgery. CONCLUSIONS: The results of this preclinical study indicate that the most viable solution to enable the safe conduct of CI and other mastoid surgery is a combination of a filtering facepiece (FFP3) mask or half-face respirator with safety spoggles as PPE. Prescription spoggles are an option for surgeons who need to wear corrective glasses to operate. A drape tent reduces droplet spread. A multicenter clinical trial to evaluate the effectiveness of PPE should be the next step toward safely performing CI surgery during the COVID-19 era. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:2693-2699, 2020.

Aerosol Dispersion During Mastoidectomy and Custom Mitigation Strategies for Otologic Surgery in the COVID-19 Era.

OBJECTIVE: To investigate small-particle aerosolization from mastoidectomy relevant to potential viral transmission and to test source-control mitigation strategies. STUDY DESIGN: Cadaveric simulation. SETTING: Surgical simulation laboratory. METHODS: An optical particle size spectrometer was used to quantify 1- to 10-µm aerosols 30 cm from mastoid cortex drilling. Two barrier drapes were evaluated: OtoTent1, a drape sheet affixed to the microscope; OtoTent2, a custom-structured drape that enclosed the surgical field with specialized ports. RESULTS: Mastoid drilling without a barrier drape, with or without an aerosol-scavenging second suction, generated large amounts of 1- to 10-µm particulate. Drilling under OtoTent1 generated a high density of particles when compared with baseline environmental levels (P < .001, U = 107). By contrast, when drilling was conducted under OtoTent2, mean particle density remained at baseline. Adding a second suction inside OtoTent1 or OtoTent2 kept particle density at baseline levels. Significant aerosols were released upon removal of OtoTent1 or OtoTent2 despite a 60-second pause before drape removal after drilling (P < .001, U = 0, n = 10, 12; P < .001, U = 2, n = 12, 12, respectively). However, particle density did not increase above baseline when a second suction and a pause before removal were both employed. CONCLUSIONS: Mastoidectomy without a barrier, even when a second suction was added, generated substantial 1- to 10-µm aerosols. During drilling, large amounts of aerosols above baseline levels were detected with OtoTent1 but not OtoTent2. For both drapes, a second suction was an effective mitigation strategy during drilling. Last, the combination of a second suction and a pause before removal prevented aerosol escape during the removal of either drape.

A Commentary on Safety Precautions for Otologic Surgery during the COVID-19 Pandemic.

There are insufficient data regarding the safety of otologic procedures in the setting of the coronavirus disease 2019 (COVID-19) pandemic. Given the proclivity for respiratory pathogens to involve the middle ear and the significant aerosolization associated with many otologic procedures, safety precautions should follow current recommendations for procedures involving the upper airway. Until preoperative diagnostic testing becomes standardized and readily available, elective cases should be deferred and emergent/urgent cases should be treated as high risk for COVID-19 exposure. Necessary otologic procedures on positive, suspected, or unknown COVID-19 status patients should be performed using enhanced personal protective equipment, including an N95 respirator and eye protection or powered air-purifying respirator (PAPR, preferred), disposable cap, disposable gown, and gloves. Powered instrumentation should be avoided unless absolutely necessary, and if performed, PAPR or sealed eye protection is recommended.