Rise in complications of acute otitis media during and after the COVID-19 pandemic.

PURPOSE: After the lifting of nonpharmaceutical interventions (NPIs) during the COVID-19 pandemic, clinical observation showed an increase in complications of acute otitis, followed by a rise in the number of mastoidectomies performed. The aim of this study was to record the number of mastoidectomies performed before, during and after the COVID-19 pandemic as an indicator for complications of acute otitis media. METHODS: Data were collected from a tertiary hospital in a university setting, as well as from four major public health insurance companies in Germany. The data of 24,824,763 German citizens during a period from 2014 until 2023 were analyzed. RESULTS: According to the data, during the COVID-19 pandemic, the number of mastoidectomies performed dropped by 54% for children aged 0-6 and by 62% for children aged 7-18. For adults, there were 30% fewer mastoidectomies performed between 2020 and 2022. After the lifting of most NPI's in the season from July 2022 to June 2023, there was a sharp increase in the number of mastoidectomies performed on patients of all ages. CONCLUSIONS: During the COVID-19 pandemic, a decrease in the number of mastoidectomies performed was seen, suggesting a lower incidence of complicated acute otitis, most likely linked to the general decrease of upper airway infections due to NPI's. In contrast, a sharp increase in the incidence of complicated otitis occurred after the hygiene measures were lifted. The current development causes a more frequent performance of mastoidectomies, thus entailing a change in the challenges for everyday clinical practice.

The curvature quantification of wave I in auditory brainstem responses detects cochlear synaptopathy in human beings.

PURPOSE: Patients with age-related hearing loss complain often about reduced speech perception in adverse listening environment. Studies on animals have suggested that cochlear synaptopathy may be one of the primary mechanisms responsible for this phenomenon. A decreased wave I amplitude in supra-threshold auditory brainstem response (ABR) can diagnose this pathology non-invasively. However, the interpretation of the wave I amplitude in humans remains controversial. Recent studies in mice have established a robust and reliable mathematic algorithm, i.e., curve curvature quantification, for detecting cochlear synaptopathy. This study aimed to determine whether the curve curvature has sufficient test-retest reliability to detect cochlear synaptopathy in aging humans. METHODS: Healthy participants were recruited into this prospective study. All subjects underwent an audiogram examination with standard and extended high frequencies ranging from 0.125 to 16 kHz and an ABR with a stimulus of 80 dB nHL click. The peak amplitude, peak latency, curvature at the peak, and the area under the curve of wave I were calculated and analyzed. RESULTS: A total of 80 individuals with normal hearing, aged 18 to 61 years, participated in this study, with a mean age of 26.4 years. Pearson correlation analysis showed a significant negative correlation between curvature and age, as well as between curvature and extended high frequency (EHF) threshold (10-16 kHz). Additionally, the same correlation was observed between age and area as well as age and EHF threshold. The model comparison demonstrated that the curvature at the peak of wave I is the best metric to correlate with EHF threshold. CONCLUSION: The curvature at the peak of wave I is the most sensitive metric for detecting cochlear synaptopathy in humans  and may be applied in routine diagnostics to detect early degenerations of the auditory nerve.

Transimpedance Matrix Can Be Used to Estimate Electrode Positions Intraoperatively and to Monitor Their Positional Changes Postoperatively in Cochlear Implant Patients.

OBJECTIVE: Accurate positioning of the electrode array during cochlear implant (CI) surgery is crucial for achieving optimal hearing outcomes. Traditionally, postoperative radiological imaging has been used to assess electrode position. Transimpedance matrix (TIM) measurements have also emerged as a promising method for assessing electrode position. This involves utilizing electric field imaging to create an electric distance matrix by analyzing voltage variations among adjacent electrodes. This study aimed to investigate the feasibility of using intraoperative TIM measurements to estimate electrode position and monitor postoperative changes. STUDY DESIGN: Retrospective cohort study. SETTING: University Medical center, tertiary academic referral center. PATIENTS: Patients undergoing CI (CI622) surgery between January 2019 and June 2022. INTERVENTION: CI electrode positions and maximal angular insertion depths (maxAID) were determined using X-ray imaging according to Stenvers' projection. The mean gradient phase (MGP) was extracted from the TIM, and a correlation between the MGP and maxAID was examined. A model was then built to estimate the maxAID using the MGP, and changes in electrode location over time were assessed using this model. MAIN OUTCOME MEASURES: Twenty-four patients were included in this study. A positive correlation between the maxAID and the MGP ( R = 0.7, p = 0.0001) was found. The established model was able to predict the maxAID with an accuracy of 27.7 ± 4.4°. Comparing intraoperative and postoperative TIM measurements, a decrease of 24.1° ± 10.7° in maxAID over time was observed. CONCLUSION: TIM measurements are useful for estimating the insertion depth of the electrode and monitoring changes in the electrode's position over time.

Effects of Intraoperative Cochlear Implant Electrode Conditioning on Impedances and Electrically Evoked Compound Action Potentials.

OBJECTIVE: The current study investigates whether, during a Cochlear Implant (CI) surgery, conditioning (i.e. applying short bursts of electrical stimulation) within a saline solution can have positive effects on subsequent intra-operative measurements. We hypothesize that, based on previous research, the impedance values will be reduced, and that the reproducibility of Electrically Evoked Compound Action Potentials (ECAPs) is improved as a result of conditioning. METHODS: We conditioned half of the electrode contacts, within a saline solution, before CI insertion, using 23 MED-EL implants. Impedance was measured for both the conditioned and non-conditioned groups at five time points. Repeated ECAP recordings were measured and compared between the conditioned and non-conditioned groups. RESULTS: Impedance of the electrode contacts were reduced by 31% after conditioning in saline solution; however, there were no clinically relevant differences after the implantation of the electrode array. The hypothesis that measurement reproducibility would be increased after conditioning could not be confirmed with our data. Within the saline solution, we observed that 44% of the electrode contacts were covered with air bubbles, which most disappeared after implantation. However, these air bubbles limited the effectiveness of the conditioning within the saline solution. Lastly, the effect of conditioning on the reference electrode stimulation was approximately 16% of the total reduction in impedance. CONCLUSION: Our data does not suggest that intraoperative conditioning is clinically required for cochlear implantation with MED-EL implants. Additionally, an in-vivo ECAP recording can be considered as a method of conditioning the electrode contacts. SIGNIFICANCE: We confirm that the common clinical practice does not need to be changed.

Comparing linear and non-linear models to estimate the appropriate cochlear implant electrode array length-are current methods precise enough?

PURPOSE: In cochlear implantation with flexible lateral wall electrode arrays, a cochlear coverage (CC) range between 70% and 80% is considered ideal for optimal speech perception. To achieve this CC, the cochlear implant (CI) electrode array has to be chosen according to the individual cochlear duct length (CDL). Here, we mathematically analyzed the suitability of different flexible lateral wall electrode array lengths covering between 70% and 80% of the CDL. METHODS: In a retrospective cross-sectional study preoperative high-resolution computed tomography (HRCT) from patients undergoing cochlear implantation was investigated. The CDL was estimated using an otosurgical planning software and the CI electrode array lengths covering 70-80% of the CDL was calculated using (i) linear and (ii) non-linear models. RESULTS: The analysis of 120 HRCT data sets showed significantly different model-dependent CDL. Significant differences between the CC of 70% assessed from linear and non-linear models (mean difference: 2.5 mm, p < 0.001) and the CC of 80% assessed from linear and non-linear models (mean difference: 1.5 mm, p < 0.001) were found. In up to 25% of the patients none of the existing flexible lateral wall electrode arrays fit into this range. In 59 cases (49,2%) the models did not agree on the suitable electrode arrays. CONCLUSIONS: The CC varies depending on the underlying CDL approximation, which critically influences electrode array choice. Based on the literature, we hypothesize that the non-linear method systematically overestimates the CC and may lead to rather too short electrode array choices. Future studies need to assess the accuracy of the individual mathematical models.

Head and Neck Cancer: A Study on the Complex Relationship between QoL and Swallowing Function.

Head and neck squamous cell carcinoma (HNSCC) is linked to significant morbidity, adversely affecting survival and functional capacity. Post-treatment challenges such as pain, dysphonia, and dysphagia are common, prompting increased attention in survivorship research. Quality of Life (QoL) questionnaires, especially the MD Anderson Dysphagia Inventory (MDADI), are prevalent outcome measures in clinical studies but often lack parallel objective swallowing function evaluations, leading to potential outcome discrepancies. This study aimed to illuminate the relationship between subjective QoL (EQ-5D-5L and MDADI) measures and objective swallowing function (evaluated via Fiberoptic Endoscopic Evaluation of Swallowing, FEES) in patients with HNSCC. The analysis revealed a notable discordance between objective measures of swallowing function, such as the Penetration-Aspiration Scale (PAS) and residue ratings in the vallecula or piriform sinus, and patients' subjective QoL assessments (p = 0.21). Despite the lack of correlation, swallowing-related QoL, as measured by the MDADI, was more indicative of disease severity than generic QoL assessments. Generic QoL scores did not demonstrate substantial variation between patients. In contrast, MDADI scores significantly declined with advancing tumor stage, multimodal therapy, and reliance on feeding tubes. However, the clinical significance of this finding was tempered by the less than 10-point difference in MDADI scores. The findings of this study underline the limitations of QoL measures as standalone assessments in patients with HNSCC, given their reliance on patient-perceived impairment. While subjective QoL is a crucial aspect of evaluating therapeutic success and patient-centric outcomes, it may fail to capture critical clinical details such as silent aspirations. Consequently, QoL assessments should be augmented by objective evaluations of swallowing function in clinical research and practice to ensure a holistic understanding of patient well-being and treatment impact.

Establishing safe high hydrostatic pressure devitalization thresholds for autologous head and neck cancer vaccination and reconstruction.

High hydrostatic pressure specifically devitalizes cells and tissues without major changes in their molecular structure. Hence, high hydrostatic pressure may enhance the development of whole-cell anti-tumor vaccines, representing tumor heterogeneity and thus (neo-) antigen diversity. Moreover, safe devitalization of tumor-infiltrated supporting tissue may facilitate reimplantation for functional reconstruction. However, precise high hydrostatic pressure thresholds for safe cancer cell killing are unknown. Here, we show that high hydrostatic pressure of at least 450 MPa is necessary to safely devitalize head and neck squamous cell cancer. A pressure of 300 MPa, which has been used frequently in cancer vaccine preparation, resulted in partial devitalization with 27% live cells in flow cytometry and 4% remaining autofluorescence in cell culture after one week. The remaining cells could form vital tumors in the chorioallantoic membrane assay. In contrast, 450 MPa killed all cells in vitro and prevented tumor outgrowth in ovo. The effectiveness of 450 MPa was attributed to the induction of DNA double-strand breaks, independent of apoptosis, autophagy, or methuosis. Furthermore, 450 MPa continued to induce immunogenic cell death. Our results demonstrate that 450 MPa of high hydrostatic pressure induces safe and sustained devitalization of head and neck cancer cells and tissues. Because of the heterogeneity in pressure resistance, we propose our approach as a starting point for determining the precise thresholds for other cancer entities. Further studies on head and neck cancer should focus on immunological co-cultures, combinations of immune checkpoint inhibition, and accurate anatomical reconstruction with pressure-treated autografts.

[Health-related quality of life in chronic otitis media-measurement methods and their application in surgical therapy]. / Gesundheitsbezogene Lebensqualität bei der chronischen Otitis media ­ Messmethoden und deren Anwendung bei chirurgischen Therapien.

BACKGROUND: Chronic otitis media (COM) can lead to significant impairment of health-related quality of life (HRQoL) due to symptoms such as otorrhea, pain, hearing loss, tinnitus, or dizziness. A systematic assessment of HRQoL in COM is becoming increasingly important as it complements (semi-)objective outcome parameters in clinical practice and research. HRQoL is measured by means of patient-reported outcome measures (PROMs). There are two disease-specific validated PROMs available for COM in German-the Chronic Otitis Media Outcome Test (COMOT-15) and the Zurich Chronic Middle Ear Inventory (ZCMEI-21)-which have become increasingly popular in recent years. OBJECTIVE: The purpose of this narrative review is to present the current state of research on measuring HRQoL in COM before and after surgical procedures. RESULTS AND CONCLUSION: Hearing is the most important factor influencing HRQoL in COM. Surgical procedures usually result in a clinically relevant improvement in HRQoL in COM with or without cholesteatoma. However, if cholesteatoma is present, its extent does not correlate with HRQoL. While HRQoL plays a secondary role in establishment of the indication for surgical therapy in COM with cholesteatoma, it plays an important role in terms of relative surgical indications, e.g., a symptomatic open mastoid cavity after resection of the posterior canal wall. We encourage the regular use of disease-specific PROMs preoperatively as well as during follow-up to assess HRQoL in COM in individual patients, in research, and in the context of quality monitoring.

Continuous intraoperative perfusion monitoring of free microvascular anastomosed fasciocutaneous flaps using remote photoplethysmography.

Flap loss through limited perfusion remains a major complication in reconstructive surgery. Continuous monitoring of perfusion will facilitate early detection of insufficient perfusion. Remote or imaging photoplethysmography (rPPG/iPPG) as a non-contact, non-ionizing, and non-invasive monitoring technique provides objective and reproducible information on physiological parameters. The aim of this study is to establish rPPG for intra- and postoperative monitoring of flap perfusion in patients undergoing reconstruction with free fasciocutaneous flaps (FFCF). We developed a monitoring algorithm for flap perfusion, which was evaluated in 15 patients. For 14 patients, ischemia of the FFCF in the forearm and successful reperfusion of the implanted FFCF was quantified based on the local signal. One FFCF showed no perfusion after reperfusion and devitalized in the course. Intraoperative monitoring of perfusion with rPPG provides objective and reproducible results. Therefore, rPPG is a promising technology for standard flap perfusion monitoring on low costs without the need for additional monitoring devices.

Volumetry improves the assessment of the vestibular aqueduct size in inner ear malformation.

OBJECTIVES: Enlarged vestibular aqueduct (EVA) is a common finding associated with inner ear malformations (IEM). However, uniform radiologic definitions for EVA are missing and various 2D-measurement methods to define EVA have been reported. This study evaluates VA volume in different types of IEM and compares 3D-reconstructed VA volume to 2D-measurements. METHODS: A total of 98 high-resolution CT (HRCT) data sets from temporal bones were analyzed (56 with IEM; [cochlear hypoplasia (CH; n = 18), incomplete partition type I (IPI; n = 12) and type II (IPII; n = 11) and EVA (n = 15)]; 42 controls). VA diameter was measured in axial images. VA volume was analyzed by software-based, semi-automatic segmentation and 3D-reconstruction. Differences in VA volume between the groups and associations between VA volume and VA diameter were assessed. Inter-rater-reliability (IRR) was assessed using the intra-class-correlation-coefficient (ICC). RESULTS: Larger VA volumes were found in IEM compared to controls. Significant differences in VA volume between patients with EVA and controls (p < 0.001) as well as between IPII and controls (p < 0.001) were found. VA diameter at the midpoint (VA midpoint) and at the operculum (VA operculum) correlated to VA volume in IPI (VA midpoint: r = 0.78, VA operculum: r = 0.91), in CH (VA midpoint: r = 0.59, VA operculum: r = 0.61), in EVA (VA midpoint: r = 0.55, VA operculum: r = 0.66) and in controls (VA midpoint: r = 0.36, VA operculum: r = 0.42). The highest IRR was found for VA volume (ICC = 0.90). CONCLUSIONS: The VA diameter may be an insufficient estimate of VA volume, since (1) measurement of VA diameter does not reliably correlate with VA volume and (2) VA diameter shows a lower IRR than VA volume. 3D-reconstruction and VA volumetry may add information in diagnosing EVA in cases with or without additional IEM.

Internal auditory canal volume in normal and malformed inner ears.

PURPOSE: A narrow bony internal auditory canal (IAC) may be associated with a hypoplastic cochlear nerve and poorer hearing performances after cochlear implantation. However, definitions for a narrow IAC vary widely and commonly, qualitative grading or two-dimensional measures are used to characterize a narrow IAC. We aimed to refine the definition of a narrow IAC by determining IAC volume in both control patients and patients with inner ear malformations (IEMs). METHODS: In this multicentric study, we included high-resolution CT (HRCT) scans of 128 temporal bones (85 with IEMs: cochlear aplasia, n = 11; common cavity, n = 2; cochlear hypoplasia type, n = 19; incomplete partition type I/III, n = 8/8; Mondini malformation, n = 16; enlarged vestibular aqueduct syndrome, n = 19; 45 controls). The IAC diameter was measured in the axial plane and the IAC volume was measured by semi-automatic segmentation and three-dimensional reconstruction. RESULTS: In controls, the mean IAC diameter was 5.5 mm (SD 1.1 mm) and the mean IAC volume was 175.3 mm3 (SD 52.6 mm3). Statistically significant differences in IAC volumes were found in cochlear aplasia (68.3 mm3, p < 0.0001), IPI (107.4 mm3, p = 0.04), and IPIII (277.5 mm3, p = 0.0004 mm3). Inter-rater reliability was higher in IAC volume than in IAC diameter (intraclass correlation coefficient 0.92 vs. 0.77). CONCLUSIONS: Volumetric measurement of IAC in cases of IEMs reduces measurement variability and may add to classifying IEMs. Since a hypoplastic IAC can be associated with a hypoplastic cochlear nerve and sensorineural hearing loss, radiologic assessment of the IAC is crucial in patients with severe sensorineural hearing loss undergoing cochlear implantation.

The Dorsal Skinfold Chamber as a New Tympanic Membrane Wound Healing Model: Intravital Insights into the Pathophysiology of Epithelialized Wounds.

BACKGROUND: Tympanic membrane perforations (TMPs) are a common complication of trauma and infection. Persisting perforations result from the unique location of the tympanic membrane. The wound is surrounded by air of the middle ear and the external auditory canal. The inadequate wound bed, growth factor, and blood supply lead to circular epithelialization of the perforation's edge and premature interruption of defect closure. Orthotopic animal models use mechanical or chemical tympanic membrane laceration to identify bioactive wound dressings and overcome premature epithelialization. However, all orthotopic models essentially lack repetitive visualization of the biomaterial-wound interface. Therefore, recent progress in 3D printing of customized wound dressings has not yet been transferred to the unique wound setup of the TMP. Here, we present a novel application for the mice dorsal skinfold chamber (DSC) with an epithelialized full-thickness defect as TMP model. METHODS: A circular 2-mm defect was cut into the extended dorsal skinfold using a biopsy punch. The skinfold was either perforated through both skin layers without prior preparation or perforated on 1 side, following resection of the opposing skin layer. In both groups, the wound was sealed with a coverslip or left unclosed (n = 4). All animals were examined for epithelialization of the edge (histology), size of the perforation (planimetry), neovascularization (repetitive intravital fluorescence microscopy), and inflammation (immunohistology). RESULTS: The edge of the perforation was overgrown by the cornified squamous epithelium in all pre-parations. Reduction in the perforation's size was enhanced by application of a coverslip. Microsurgical preparation before biopsy punch perforation and sealing with a coverslip enabled repetitive high-quality intravital fluorescence microscopy. However, spontaneous reduction of the perforation occurred frequently. Therefore, the direct biopsy punch perforation without microsurgical preparation was favorable: spontaneous reduction did not occur throughout 21 days. Moreover, the visualization of the neovascularization was sufficient in intravital microscopy. CONCLUSIONS: The DSC full-thickness defect is a valuable supplement to orthotopic TMP models. Repetitive intravital microscopy of the epithelialized edge enables investigation of the underlying pathophysiology during the transition from the inflammation to the proliferation phase of wound healing. Using established analysis procedures, the present model provides an effective platform for the screening of bioactive materials and transferring progress in tissue engineering to the special conditions of tympanic membrane wound healing.

Effect of Cochlear Implant Electrode Insertion Depth on Speech Perception Outcomes: A Systematic Review.

Objective: The suitable electrode array choice is broadly discussed in cochlear implantation surgery. Whether to use a shorter electrode length under the aim of structure preservation versus choosing a longer array to achieve a greater cochlear coverage is a matter of debate. The aim of this review is to identify the impact of the insertion depth of a cochlear implant (CI) electrode array on CI users' speech perception outcomes. Databases Reviewed: PubMed was searched for English-language articles that were published in a peer-reviewed journal from 1997 to 2022. Methods: A systematic electronic search of the literature was carried out using PubMed to find relevant literature on the impact of insertion depth on speech perception. The review was conducted according to the preferred reporting items for systematic reviews and meta-analyses guidelines of reporting. Studies in both, children and adults with pre- or postlingual hearing loss, implanted with a CI were included in this study. Articles written in languages other than English, literature reviews, meta-analyses, animal studies, histopathological studies, or studies pertaining exclusively to imaging modalities without reporting correlations between insertion depth and speech outcomes were excluded. The risk of bias was determined using the "Risk of Bias in Nonrandomized Studies of Interventions" tool. Articles were extracted by 2 authors independently using predefined search terms. The titles and abstracts were screened manually to identify studies that potentially meet the inclusion criteria. The extracted information included: the study population, type of hearing loss, outcomes reported, devices used, speech perception outcomes, insertion depth (linear insertion depth and/or the angular insertion depth), and correlation between insertion depth and the speech perception outcomes. Results: A total of 215 relevant studies were assessed for eligibility. Twenty-three studies met the inclusion criteria and were analyzed further. Seven studies found no significant correlation between insertion depth and speech perception outcomes. Fifteen found either a significant positive correlation or a positive effect between insertion depth and speech perception. Only 1 study found a significant negative correlation between insertion depth and speech perception outcomes. Conclusion: Although most studies reported a positive effect of insertion depth on speech perception outcomes, one-third of the identified studies reported no correlation. Thus, the insertion depth must be considered as a contributing factor to speech perception rather than as a major decisive criterion. Registration: This review has been registered in PROSPERO, the international prospective register of systematic reviews (CRD42021257547), available at https://www.crd.york.ac.uk/PROSPERO/.

[Considerations for the Performance and Quality Assurance of Outpatient Surgery in Otorhinolaryngology, Head and Neck Surgery in Germany]. / Erwägungen zur Durchführung und Qualitätssicherung ambulanter Operationen im HNO-Bereich in Deutschland.

BACKGROUND: German health policy has propagated an expansion of outpatient surgeries and procedures and initiated the discussion about this. Otorhinolaryngology, head and neck surgery offers opportunities to provide currently inpatient procedures on an outpatient basis. METHODS: The German Society of Otorhinolaryngology, Head and Neck Surgery, and the German Professional Association of Otorhinolaryngologists established working groups to assess and evaluate the ENT-specific aspects of shifting services to the outpatient setting. The working groups were given the task of developing and considering organizational, structural and personnel definitions of quality assurance. RECOMMENDATION: Facts were determined in detail, which exclude an ambulatory operation in the ENT-specialty. This was based on both surgery-related and patient-related facts. Finally, operations were named which can be performed as outpatient operations. DISCUSSION: An evaluation was performed from the ENT specialist's perspective. A prerequisite for outpatient treatment is a reorganization of remuneration. The current DRG and EBM system do not provide a satisfactory framework for this, and the EBM does not allow for the economic provision of surgical interventions in otorhinolaryngology, head and neck surgery. The development of an appropriate financing model is as imperative for a successful implementation as the integration and financing of further training of ENT physicians.

Minimally Traumatic Cochlear Implant Surgery: Expert Opinion in 2010 and 2020.

This study aimed to discover expert opinion on the surgical techniques and materials most likely to achieve maximum postoperative residual hearing preservation in cochlear implant (CI) surgery and to determine how these opinions have changed since 2010. A previously published questionnaire used in a study published in 2010 was adapted and expanded. The questionnaire was distributed to an international group of experienced CI surgeons. Present results were compared, via descriptive statistics, to those from the 2010 survey. Eighteen surgeons completed the questionnaire. Respondents clearly favored the following: round window insertion, slow array insertion, and the peri- and postoperative use of systematic antibiotics. Insertion depth was regarded as important, and electrode arrays less likely to induce trauma were preferred. The usefulness of dedicated soft-surgery training was also recognized. A lack of agreement was found on whether the middle ear cavity should be flushed with a non-aminoglycoside antibiotic solution or whether a sheath or insertion tube should be used to avoid contaminating the array with blood or bone dust. In conclusion, this paper demonstrates how beliefs about CI soft surgery have changed since 2010 and shows areas of current consensus and disagreement.

[Interactive intraoperative annotation of surgical landmarks in student education to support learning efficiency and motivation]. / Interaktive intraoperative Annotation chirurgischer Anatomie in der studentischen Ausbildung zur Unterstützung der Lerneffizienz und -motivation.

BACKGROUND: The development of technological innovations has not only changed social life and the healthcare system, but also affects medical education. The aim of this pilot study was to evaluate whether students, when observing a microsurgical procedure of the temporal bone, gain an additional understanding of the anatomical structures and surgical site when visualization is used that provides identical views for the surgeon and viewer in 3D. MATERIALS AND METHODS: During regular attendance tutorials, students were randomly assigned to three different groups: control group, 2D group, or 3D group. Evaluation questionnaires and intraoperative student annotation of the surgical view were used to assess the subjective didactic value of different visualization formats and resultant learning experiences for the students. RESULTS: A total of 47 students were included in the investigations during conventional attendance tutorials. The majority indicated a high added value of the 3D visualization in terms of method (70%) and vividness (80%) compared to the 2D group and self-study; 69% of the students fully agreed with the statement that 2D and 3D visualization increases learning motivation and is a very good way to improve recognition of anatomical topography and structures. CONCLUSION: New interactive visualization options in teaching promote learning efficiency and motivation among students. Especially 3D visualization and intraoperative annotation of the surgical view by the student is a useful didactic tool and increases the quality of clinical teaching. It supports the perception of anatomical topography and enables more focused surgical training.

Surgical management of tympanojugular paragangliomas using the flexible CO2 laser.

PURPOSE: Surgery is a standard therapy for tympanojugular paragangliomas (TJP). Maintaining the quality of life (QoL) requires functional preservation. The flexible CO2 laser allows contact-free tumor removal. This retrospective study compares the postoperative functional outcomes of TJP surgery with and without the flexible CO2 laser. METHODS: Between 2005 and 2019, 51 patients with TJP were surgically treated at a tertiary hospital. Until 2012, 17 patients received conventional surgery. Thereafter, the flexible laser was used in 34 patients. Tumor extend, pre- and postoperative cranial nerve function, and complications were compared between the groups. RESULTS: The cohort consisted of 33 class A and B tumors and 18 class C and D tumors. Preoperative embolization was performed in 17 cases. Class C/D TJP were usually removed via an infratemporal fossa type A approach. Gross total tumor removal was achieved in 14/18 class C/D tumors. 3/51 patients suffered from long-term partial or complete facial palsy. No differences in post-therapeutic cranial nerve function or complications were noted between the conventional and laser group. One recurrence was observed after complete tumor resection. CONCLUSION: The flexible CO2 laser was shown to be a safe and effective alternative to conventional bipolar cauterization, which is appreciated by the surgeon in these highly vascularized tumors. Both techniques allowed a high tumor control rate and good long-term results also from a functional point of view.

Smartphone-based nystagmus diagnostics: development of an innovative app for the targeted detection of vertigo.

BACKGROUND: In medicine, the symptom of dizziness is one of the most common multidisciplinary causes of emergency medical presentation. Attending physicians are often faced with difficult decisions when evaluating patients with dizziness. A rapid differential diagnostic decision must be made during the initial examination. The goal of this study, was to develop a smartphone-based app that can diagnose and qualify nystagmus. The app should enable differentiation between acute emergencies such as strokes ("central vertigo") and vestibular disorders ("peripheral vertigo") using and recognizing or analyzing the accompanying symptom "nystagmus". MATERIALS AND METHODS: This prospective study was conducted at the Department of Otolaryngology, Head and Neck Surgery "Otto Körner", Rostock (Germany). The experimental study design consisted of two test runs and two control runs. In the two test runs, nystagmus was tracked and evaluated by caloric and optokinetic stimulation, respectively, through a custom-developed app. Sensitivity and correlation were calculated for the app's application performance and compared under different experimental conditions. RESULTS: The patient sample included twenty healthy participants with a mean age of 25.6 years (± 2.2 SD) who participated in the study. The overall sensitivity of detection of nystagmus averaged 82.14% in the optokinetic stimulation test trials. There is no correlation regarding specific subject data and sensitivity. CONCLUSIONS: The results of our experimental validation study show that a smartphone-based nystagmus app is a useful tool for vertigo diagnosis. The results of our analyses show that it is possible to diagnose nystagmus and determine shape or direction with the app.

Suitable Electrode Choice for Robotic-Assisted Cochlear Implant Surgery: A Systematic Literature Review of Manual Electrode Insertion Adverse Events.

Background and Objective: The cochlear implant (CI) electrode insertion process is a key step in CI surgery. One of the aims of advances in robotic-assisted CI surgery (RACIS) is to realize better cochlear structure preservation and to precisely control insertion. The aim of this literature review is to gain insight into electrode selection for RACIS by acquiring a thorough knowledge of electrode insertion and related complications from classic CI surgery involving a manual electrode insertion process. Methods: A systematic electronic search of the literature was carried out using PubMed, Scopus, Cochrane, and Web of Science to find relevant literature on electrode tip fold over (ETFO), electrode scalar deviation (ESD), and electrode migration (EM) from both pre-shaped and straight electrode types. Results: A total of 82 studies that include 8,603 ears implanted with a CI, i.e., pre-shaped (4,869) and straight electrodes (3,734), were evaluated. The rate of ETFO (25 studies, 2,335 ears), ESD (39 studies, 3,073 ears), and EM (18 studies, 3,195 ears) was determined. An incidence rate (±95% CI) of 5.38% (4.4-6.6%) of ETFO, 28.6% (26.6-30.6%) of ESD, and 0.53% (0.2-1.1%) of EM is associated with pre-shaped electrodes, whereas with straight electrodes it was 0.51% (0.1-1.3%), 11% (9.2-13.0%), and 3.2% (2.5-3.95%), respectively. The differences between the pre-shaped and straight electrode types are highly significant (p < 0.001). Laboratory experiments show evidence that robotic insertions of electrodes are less traumatic than manual insertions. The influence of round window (RW) vs. cochleostomy (Coch) was not assessed. Conclusion: Considering the current electrode designs available and the reported incidence of insertion complications, the use of straight electrodes in RACIS and conventional CI surgery (and manual insertion) appears to be less traumatic to intracochlear structures compared with pre-shaped electrodes. However, EM of straight electrodes should be anticipated. RACIS has the potential to reduce these complications.

Tonsillar swabs and sputum predict SLPI- and AnxA2 expression in tonsils: A prospective study on smoking dependent SLPI- and AnxA2-expression, and tonsillar HPV infection.

Previous retrospective studies have elucidated a correlation between secretory leucocyte protease inhibitor (SLPI) and Annexin A2 (AnxA2), patient smoking status and tonsillar human papilloma virus (HPV) status. The current study assessed these parameters prospectively and to the best of our knowledge, analyzed SLPI-/AnxA2-expression for the first time in tonsillar swabs and sputum. Samples were obtained from 52 patients with tonsillar squamous cell carcinoma and 163 patients with tonsillar hyperplasia (H; n=56) and chronic or recurrent tonsillitis (CRT; n=107). HPV-DNA, SLPI and AnxA2 gene expression was analyzed in sputum, tonsillar swabs and tissue by performing reverse transcription-quantitative PCR. Results were compared with smoking status, revealing that smoking resulted in significantly increased SLPI gene expression in all biomaterials of all cases. SLPI-gene expression was significantly decreased in all HPV-DNA-positive samples (tissue/swab/sputum), while AnxA2 was significantly increased in all HPV-DNA-positive samples. Results from swabs and sputum were able to predict SLPI- and AnxA2 gene expression of the corresponding tonsil. The current prospective study confirmed previous retrospective results underlining this hypothesis: Smoking enhances SLPI-expression, preventing HPV-binding to AnxA2. HPV-binding to AnxA2 appears essential for successful cell-entry. SLPI/AnxA2-gene expression in swabs and sputum reflect their expression in tonsillar tissue. Accordingly, a positive AnxA2/SLPI-ratio in sputum/swabs could possibly be used to reduce HPV-associated carcinogenesis, by performing tonsillectomy or HPV-vaccination in patients with positive AnxA2/SLPI-ratios.