Novel approach for tracheal resection in Morquio a syndrome with end-stage critical airway obstruction: a UK case series.

BACKGROUND: Mucopolysaccharidosis (MPS) type IVA is a rare lysosomal storage disorder caused by aberrations of the N-acetyl-galactosamine-6-sulfatase (GALNS) enzyme. MPS IVA is associated with a wide gamut of respiratory and airway disorders that manifest in a continuum of severity. In individuals exhibiting severe phenotypic expression, terminal stages of the disease frequently culminate in life-threatening, critical airway obstruction. These manifestations of end-stage disease are engendered by an insidious progression of multi-level airway pathologies, comprising of tracheomalacia, stenosis, tortuosity and 'buckling'. Historically, the management of end-stage airway disease has predominantly leaned towards palliative modalities. However, contemporary literature has posited that the potential benefits of tracheal resection with aortopexy, performed under cardiopulmonary bypass (CPB), may offer a promising therapeutic option. In this context, we report on outcomes from patients undergoing a novel approach to tracheal resection that is combined with manubrial resection, leading to improved airway calibre, obviating the requisition for CPB. RESULTS: In this study, seven patients with severe MPS IVA exhibited clinical symptoms and radiological evidence indicative of advanced airway obstruction. All patients had a tracheal resection with a partial upper manubriectomy via transcervical approach, which did not require CPB. The surgical cohort consisted of 5 females and 2 males, the median age was 16 years (range 11-19) and the median height was 105.6cm (range 96.4-113.4). Postoperatively, significant improvements were seen in forced expiratory volume in 1 second (FEV1), with a mean increase of 0.68 litres (95% CI: 0.45-0.91; SD: 0.20). Notably, other spirometry variables also showed meaningful improvements, providing evidence of positive treatment effects. Furthermore, there were no major long-term complications, and the procedure resulted in a significant enhancement in patient-reported domains using PedsQL (version 4.0). CONCLUSIONS: This study represents the largest case series to date, on tracheal resection in patients with severe MPS IVA. Our findings demonstrate the effectiveness of the transcervical approach with partial manubriectomy for improving respiratory function and quality of life for individuals with advanced airway obstruction. Tracheal resection presents a promising treatment modality for severe cases of MPS IVA. Successful outcomes rely on meticulous multidisciplinary assessment, judicious decision-making, and appropriate timing of tracheal surgery. Further research and long-term follow-up studies are warranted to validate the long-term efficacy and safety of this approach.

Hearing preservation in paediatric cochlear implantation with the Nucleus Slim Straight Electrode - our experience.

OBJECTIVE: to evaluate the levels of successful hearing preservation and preservation of functional hearing following cochlear implantation (HPCI) in children using the Cochlear Nucleus® Slim Straight Electrode (SSE). DESIGN: retrospective case note review of paediatric HPCI cases in our CI centre from 2013 to 2023. Inclusion criteria were attempted hearing preservation surgery, SSE used for implantation, pre-operative hearing thresholds ≤80dBHL at 250 Hz, CI before 18 years of age. Patients were excluded if no postoperative unaided PTA was obtained (poor attendance). Primairy outcome was hearing preservation using the HEARRING group formula; secondary outcome was residual functional hearing (≤80dBHL at 250 Hz/<90dB LFPTA). STUDY SAMPLE: 56 patients with 94 CI's were included for review. RESULTS: Hearing preservation was achieved in 94.7% (89/94) of ears and complete preservation in 72% (68/94)). Average functional hearing was preserved in 89% using both criteria for preservation. Long-term follow up data was available for 36 ears (average 35.2 months), demonstrating 88.9% (32/36) complete preservation. CONCLUSION: We have reliably achieved and maintained a high success rate of HPCI using the SSE in our paediatric population. The field of HPCI would benefit from unification of outcome reporting in order to optimise the evidence available to professionals, patients and their carers.

Risk factors associated with the development of chronic suppurative otitis media in children: Systematic review and meta-analysis.

OBJECTIVES: Chronic suppurative otitis media (CSOM) is defined as persistent discharge through a tympanic membrane perforation for greater than 2 weeks. It is associated with a significant disease burden, including hearing loss, and reducing its incidence could significantly improve short- and long-term health. We aimed to identify risk factors associated with the development of CSOM in children. DESIGN AND SETTING: Systematic review and meta-analysis of studies set in community, primary and secondary care settings, identified from Medline, Embase and Cochrane databases from 2000 to 2022. PARTICIPANTS: Children 16 years old and below. MAIN OUTCOME MEASURES: Clinical diagnosis of CSOM. RESULTS: In total, 739 papers were screened, with 12 deemed eligible for inclusion in the systematic review, of which, 10 were included in the meta-analysis. Risk factors examined included perinatal, patient, dietary, environmental and parental factors. Meta-analysis results indicate that atopy (RR = 1.18, 95% CI [1.01-1.37], p = .04, 2 studies); and birth weight <2500 g (RR = 1.79 [1.27-2.50], p < .01, 2 studies) are associated with an increased risk of CSOM development. Factors not associated were male sex (RR = 0.96 [0.82-1.13], p = .62, 8 studies); exposure to passive smoking (RR = 1.27 [0.81-2.01], p = .30, 3 studies); and parental history of otitis media (RR = 1.14 [0.59-2.20], p = .69, 2 studies). CONCLUSION: Optimal management of risk factors associated with CSOM development will help reduce the burden of disease and prevent disease progression or recurrence. The current quality of evidence in the literature is variable and heterogeneous. Future studies should aim to use standardised classification systems to define risk factors to allow meta-analysis.

Outcome measures for use in trials of paediatric otorrhoea: A systematic review.

INTRODUCTION: Paediatric otorrhoea (PO) describes a middle ear infection that results in a perforation of the tympanic membrane and ear discharge, in children and young people (CYP). Prolonged infection may be associated with hearing loss and developmental delay. The current management of paediatric otorrhoea is variable, including non-invasive treatments (conservative, oral antibiotics, topical antibiotics) and surgery, reflecting the lack of a sufficiently strong evidence base. Outcome reporting is fundamental to producing reliable and meaningful evidence to inform best practice. OBJECTIVES: Primary objective: to determine which outcome measures are currently used to evaluate treatment success in studies of non-surgical treatments for paediatric otorrhoea. SECONDARY OBJECTIVES: to identify outcome measurement instruments used in the literature and assess their applicability for use in clinical trials of PO. METHODS: This systematic review was registered with PROSPERO (CRD42023407976). Database searches of EMBASE, MEDLINE and Cochrane was performed on June 6, 2023, covering from Jan 1995 to May 2023. Randomised controlled trials or study protocols involving CYP with PO were included following PRISMA guidelines. Risk of bias was assessed with Cochrane's tool. RESULTS: Of the 377 papers identified, six were included in the systematic review. The primary outcome of five of the studies related to otorrhoea cessation; both time to cessation and proportion recovered at various time points were used as measures. Two measurement instruments were identified: Otitis Media-6 Questionnaire and the Institute for Medical Technology Assessment Productivity Cost Questionnaire. Both were shown to be applicable measurement instruments when used in clinical trials of PO. CONCLUSIONS: To promote homogeneity and facilitate meaningful comparison and combination of studies, we propose that time to cessation of otorrhoea from onset of otorrhoea should be used as the primary outcome in future studies. Further research is needed to establish if this is the most important outcome to children and their caregivers.

Enlarged Vestibular Aqueduct and Associated Inner Ear Malformations: Hearing Loss Prognostic Factors and Data Modeling from an International Cohort.

ACKGROUND: There is a need to operationalize existing clinical data to support precision medicine in progressive hearing loss (HL). By utilizing enlarged vestibular aqueduct (EVA) and its associated inner ear abnormalities as an exemplar, we model data from a large international cohort, confirm prognostic factors for HL, and explore the potential to generate a prediction model to optimize current management paradigms. METHODS: An international retrospective cohort study. Regression analyses were utilized to model frequency-specific HL and identify prognostic factors for baseline average HL severity and progression. Elastic-net regression and machine learning (ML) techniques were utilized to predict future average HL progression based upon routinely measurable clinical, genetic, and radiological data. RESULTS: Higher frequencies of hearing were lost more severely. Prognostic factors for HL were the presence of incomplete partition type 2 (coefficient 12.95 dB, P=.011, 95% CI 3.0-22 dB) and presence of sac signal heterogeneity (P=.009, 95% CI 0.062-0.429) on magnetic resonance imaging. Elastic-net regression outperformed the ML algorithms (R2 0.32, mean absolute error 11.05 dB) with coefficients for baseline average hearing level and the presence of sac heterogeneity contributing the most to prediction outcomes. CONCLUSION: Incomplete partition type 2 and endolymphatic sac signal heterogeneity phenotypes should be monitored closely for hearing deterioration and need for early audiological rehabilitation/cochlear implant. Preliminary prediction models have been generated using routinely collected health data in EVA. This study showcases how international collaborative research can use exemplar techniques to improve precision medicine in relatively rare disease entities.

Protocol for the Paediatric Otorrhoea Study (POSt): a multi-methods study to understand the burden of paediatric otorrhoea in the UK.

INTRODUCTION: Paediatric otorrhoea (PO) refers to the leakage of fluid through a perforation in the ear drum, resulting from an infection of the middle ear of a child or young person (CYP). PO frequently results in hearing loss which may lead to developmental delay, restricted communication and reduced educational attainment.Epidemiological information for PO is largely derived from low-income countries. The aim of this study will be to establish the incidence of PO within the UK and to understand the impact of PO on CYP and their families' everyday lives. It will build the foundations for a randomised controlled trial investigating the best antibiotic treatment for PO. METHODS AND ANALYSIS: The study will consist of two work packages. (1) Data from the Clinical Practice Research Datalink (CPRD), January 2005 to July 2021, will be used to determine the incidence of patient presentations with PO to primary care in the UK. It will also explore the current antimicrobial prescribing practice for PO in primary care. (2) Thirty semi-structured interviews will be conducted from 13 July to 31 October 2023 with CYP and their parents/carers to help identify the impact of PO on everyday life, the patient journey and how service users define treatment success. Three medical professional focus groups will be used to understand the current management practice, how treatment success is measured and acceptability to randomise patients. Thematic analysis will be used. ETHICS AND DISSEMINATION: The Health Research Authority, The Health and Social Care Research Ethics Committee (23/NI/0082) and the CPRD's research data governance panel (22_002508) reviewed this study. Results will be disseminated at medical conferences, in peer-reviewed journals and via social media. The study will cocreate a webpage on healthtalk.org, with the Dipex Charity, about PO to ensure members of the public can learn more about the condition. TRIAL REGISTRATION NUMBER: ISRCTN46071200.

Can MRI biomarkers for hearing loss in enlarged vestibular aqueduct be measured reproducibly?

OBJECTIVE: Morphological features of an enlarged endolymphatic duct (ED) and sac (ES) are imaging biomarkers for genotype and hearing loss phenotype. We determine which biomarkers can be measured in a reproducible manner, facilitating further clinical prediction studies in enlarged vestibular aqueduct hearing loss. METHODS: A rater reproducibility study. Three consultant radiologists independently measured previously reported MRI ED & ES biomarkers (ED midpoint width, maximal ED diameter closest to the vestibule, ES length, ES width and presence of ES signal heterogeneity) and presence of incomplete partition Type 2 from 80 ears (T2 weighted axial MRI). Interclass correlation coefficients (ICC) and Gwet's Agreement Coefficients (AC) were generated to give a measure of reproducibility for both continuous and categorical feature measures respectively. RESULTS: ES length, width and sac signal heterogeneity showed adequate reproducibility (ICC 95% confidence intervals 0.77-0.95, Gwet's AC for sac heterogeneity 0.64). When determining ED midpoint width, measurements from multiple raters are required for "good" reliability (ICC 95% CI 0.75-0.89). Agreement on the presence of incomplete partition Type 2 ranged from "moderate" to "substantial". CONCLUSIONS: Regarding MR imaging, the opinion of multiple expert raters should be sought when determining the presence of an enlarged ED defined by midpoint width. ED midpoint, ES length, width and signal heterogeneity have adequate reproducibility to be further explored as clinical predictors for audiological phenotype. ADVANCES IN KNOWLEDGE: We report which ED & ES biomarkers are reproducibly measured. Researchers can confidently utilise these specific biomarkers when modelling progressive hearing loss associated with enlarged vestibular aqueduct.

Aided Cortical Auditory Evoked Potentials in Infants With Frequency-Specific Synthetic Speech Stimuli: Sensitivity, Repeatability, and Feasibility.

OBJECTIVES: The cortical auditory evoked potential (CAEP) test is a candidate for supplementing clinical practice for infant hearing aid users and others who are not developmentally ready for behavioral testing. Sensitivity of the test for given sensation levels (SLs) has been reported to some degree, but further data are needed from large numbers of infants within the target age range, including repeat data where CAEPs were not detected initially. This study aims to assess sensitivity, repeatability, acceptability, and feasibility of CAEPs as a clinical measure of aided audibility in infants. DESIGN: One hundred and three infant hearing aid users were recruited from 53 pediatric audiology centers across the UK. Infants underwent aided CAEP testing at age 3 to 7 months to a mid-frequency (MF) and (mid-)high-frequency (HF) synthetic speech stimulus. CAEP testing was repeated within 7 days. When developmentally ready (aged 7-21 months), the infants underwent aided behavioral hearing testing using the same stimuli, to estimate the decibel (dB) SL (i.e., level above threshold) of those stimuli when presented at the CAEP test sessions. Percentage of CAEP detections for different dB SLs are reported using an objective detection method (Hotellings T 2 ). Acceptability was assessed using caregiver interviews and a questionnaire, and feasibility by recording test duration and completion rate. RESULTS: The overall sensitivity for a single CAEP test when the stimuli were ≥0 dB SL (i.e., audible) was 70% for the MF stimulus and 54% for the HF stimulus. After repeat testing, this increased to 84% and 72%, respectively. For SL >10 dB, the respective MF and HF test sensitivities were 80% and 60% for a single test, increasing to 94% and 79% for the two tests combined. Clinical feasibility was demonstrated by an excellent >99% completion rate, and acceptable median test duration of 24 minutes, including preparation time. Caregivers reported overall positive experiences of the test. CONCLUSIONS: By addressing the clinical need to provide data in the target age group at different SLs, we have demonstrated that aided CAEP testing can supplement existing clinical practice when infants with hearing loss are not developmentally ready for traditional behavioral assessment. Repeat testing is valuable to increase test sensitivity. For clinical application, it is important to be aware of CAEP response variability in this age group.

Mixed Reality Enhanced Otolaryngology Case-Based Learning: A Randomized Educational Study.

INTRODUCTION: The COVID-19 pandemic has caused unprecedented disruptions to medical education. Education in medical specialties, such as otolaryngology faces multiple challenges, including reduced bedside and "hands-on" training opportunities at all levels. Educators are turning to technological advancements to deliver effective remote medical education. This study investigated the value of enhancing traditional remote case-based teaching with the HoloLens2™. METHODS: We present a randomized educational design study. All educational content, media, and learning outcomes were identical. Primary outcome measures included student performance as measured with pre- and post-intervention quizzes and student engagement as measured by a tally-mark system. Secondary outcome measures, collected using feedback questionnaires, included perceived enjoyment, engagement, and opinions regarding the educational role of this technology. RESULTS: The undergraduate medical students were randomized to either conventional or HoloLens2™ enhanced remote case-based teaching (n = 56). HoloLens2™ enhanced teaching improved student performance by an average of 3 marks of 15% (p < 0.001). It was engaging and encouraged questions 4-fold per session (p < 0.05) when compared to conventional remote case-based teaching. There was no significant difference in overall objective measurements of engagement. Students taught using HoloLens2™ agreed that the teaching was enjoyable, effective in concept demonstration, and encouraged engagement. CONCLUSIONS: Remote teaching has allowed for the continuation of medical education in uncertain times. Beyond COVID-19, we predict that there will be a paradigm shift toward remote learning as new technological advancements emerges. These novel technologies may prove invaluable in the future potentially enabling education to be delivered between different hospitals, universities, and even overseas. LEVEL OF EVIDENCE: NA Laryngoscope, 133:1606-1613, 2023.

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.

The Core Rehabilitation Outcome Set for Single-Sided Deafness (CROSSSD) study: International consensus on outcome measures for trials of interventions for adults with single-sided deafness.

BACKGROUND: Single-sided deafness (SSD) has functional, psychological, and social consequences. Interventions for adults with SSD include hearing aids and auditory implants. Benefits and harms (outcome domains) of these interventions are until now reported inconsistently in clinical trials. Inconsistency in reporting outcome measures prevents meaningful comparisons or syntheses of trial results. The Core Rehabilitation Outcome Set for Single-Sided Deafness (CROSSSD) international initiative used structured communication techniques to achieve consensus among healthcare users and professionals working in the field of SSD. The novel contribution is a set of core outcome domains that experts agree are critically important to assess in all clinical trials of SSD interventions. METHODS: A long list of candidate outcome domains compiled from a systematic review and published qualitative data, informed the content of a two-round online Delphi survey. Overall, 308 participants from 29 countries were enrolled. Of those, 233 participants completed both rounds of the survey and scored each outcome domain on a 9-point scale. The set of core outcome domains was finalised via a web-based consensus meeting with 12 participants. Votes involved all stakeholder groups, with an approximate 2:1 ratio of professionals to healthcare users participating in the Delphi survey, and a 1:1 ratio participating in the consensus meeting. RESULTS: The first round of the survey listed 44 potential outcome domains, organised thematically. A further five outcome domains were included in Round 2 based on participant feedback. The structured voting at round 2 identified 17 candidate outcome domains which were voted on at the consensus meeting. Consensus was reached for a core outcome domain set including three outcome domains: spatial orientation, group conversations in noisy social situations, and impact on social situations. Seventy-seven percent of the remaining Delphi participants agreed with this core outcome domain set. CONCLUSIONS: Adoption of the internationally agreed core outcome domain set would promote consistent assessment and reporting of outcomes that are meaningful and important to all relevant stakeholders. This consistency will in turn enable comparison of outcomes reported across clinical trials comparing SSD interventions in adults and reduce research waste. Further research will determine how those outcome domains should best be measured.

Enlarged Vestibular Aqueduct: Disease Characterization and Exploration of Potential Prognostic Factors for Cochlear Implantation.

OBJECTIVES: There is an unmet need to match the anticipated natural history of hearing loss (HL) in enlarged vestibular aqueduct (EVA) with clinical management strategies. The objectives of this study are therefore to provide a detailed case characterization of an EVA cohort and explore the relationship between candidate prognostic factors and timing of cochlear implant (CI) surgery. STUDY DESIGN: A multicenter retrospective review of patients diagnosed with EVA. SETTING: Patient data recruitment across three CI centers in the UK. PATIENTS: One hundred fifty patients with a radiological diagnosis of EVA from January 1995 to January 2021. MAIN OUTCOME MEASURES: Age at audiological candidacy for CI and age at first implant surgery. RESULTS: EVA was predominately a bilateral condition (144/ 150) with increased prevalence in women (M:F, 64:86). 51.7% of patients failed new-born hearing screening, with 65.7% having HL diagnosed by 1 year. Initial moderate to severe and severe to profound HL were reported most frequently. In 123 patients, median age that audiological candidacy for CI was met for at least one ear was 2.75 years. Median age at first CI was 5 years (140/150).Pendred syndrome (confirmed in 73 patients) and ethnicity, were not significantly associated with earlier CI surgery. Multivariate linear regression demonstrated that male patients have first CI surgery significantly earlier than females (coefficient -0.43, 95% CI [-0.82, -0.05), p-value = 0.028). CONCLUSIONS: This large UK EVA cohort provides evidence that patients should be closely monitored for CI candidacy within the first 3 years of life. Significantly, male gender is emerging as an independent prognostic factor for earlier assessment and first CI surgery.

Addressing the need for patient-friendly medical communications: adaptation of the 2019 recommendations for the management of MPS VI and MPS IVA.

BACKGROUND: Patients are the most important stakeholders in the care of any disease and have an educational need to learn about their condition and the treatment they should receive. Considering this need for patient-focused materials, we present a directed approach for mucopolysaccharidosis (MPS) VI and MPS IVA, a pair of rare, inherited diseases that affects multiple organs and parts of the body. Independent guidelines on the treatment of these diseases were recently published, providing evidence- and expertise-driven recommendations to optimize patient management. However, while healthcare providers may have the training and knowledge to understand these guidelines, patients and their caregivers can find the technical content challenging. Hence, we aimed to develop plain language summaries (PLS) of the MPS VI and MPS IVA guidelines with patients as the primary audience. RESULTS: A review of the guidelines by an expert team identified six domains of information relevant to patients: The multidisciplinary team, regular tests and check-ups, disease-modifying and supportive treatments, general anesthetics, ear-nose-throat/respiratory care, and surgeries. This information was adapted into a series of infographics specific to either MPS VI or MPS IVA, designed to appeal to patients and clearly present information in a concise manner. CONCLUSIONS: The use of patient-friendly materials, like the infographics we have developed, has the potential to better inform patients and engage them in their care. We issue a "call to arms" to the medical community for the development of similar PLS materials in rare diseases intended to inform and empower patients.

Rapid Point-of-Care Genotyping to Avoid Aminoglycoside-Induced Ototoxicity in Neonatal Intensive Care.

Importance: Aminoglycosides are commonly prescribed antibiotics used for the treatment of neonatal sepsis. The MT-RNR1 m.1555A>G variant predisposes to profound aminoglycoside-induced ototoxicity (AIO). Current genotyping approaches take several days, which is unfeasible in acute settings. Objective: To develop a rapid point-of-care test (POCT) for the m.1555A>G variant before implementation of this technology in the acute neonatal setting to guide antibiotic prescribing and avoid AIO. Design, Setting, and Participants: This pragmatic prospective implementation trial recruited neonates admitted to 2 large neonatal intensive care units between January 6, 2020, and November 30, 2020, in the UK. Interventions: Neonates were tested for the m.1555A>G variant via the rapid POCT on admission to the neonatal intensive care unit. Main Outcomes and Measures: The primary outcome assessed the proportion of neonates successfully tested for the variant of all infants prescribed antibiotics. Secondary outcomes measured whether implementation was negatively associated with routine clinical practice and the performance of the system. The study was statistically powered to detect a significant difference between time to antibiotic administration before and after implementation of the MT-RNR1 POCT. Results: A total of 751 neonates were recruited and had a median (range) age of 2.5 (0-198) days. The MT-RNR1 POCT was able to genotype the m.1555A>G variant in 26 minutes. Preclinical validation demonstrated a 100% sensitivity (95% CI, 93.9%-100.0%) and specificity (95% CI, 98.5%-100.0%). Three participants with the m.1555A>G variant were identified, all of whom avoided aminoglycoside antibiotics. Overall, 424 infants (80.6%) receiving antibiotics were successfully tested for the variant, and the mean time to antibiotics was equivalent to previous practice. Conclusions and Relevance: The MT-RNR1 POCT was integrated without disrupting normal clinical practice, and genotype was used to guide antibiotic prescription and avoid AIO. This approach identified the m.1555A>G variant in a practice-changing time frame, and wide adoption could significantly reduce the burden of AIO.

Personalised virtual gene panels reduce interpretation workload and maintain diagnostic rates of proband-only clinical exome sequencing for rare disorders.

PURPOSE: The increased adoption of genomic strategies in the clinic makes it imperative for diagnostic laboratories to improve the efficiency of variant interpretation. Clinical exome sequencing (CES) is becoming a valuable diagnostic tool, capable of meeting the diagnostic demand imposed by the vast array of different rare monogenic disorders. We have assessed a clinician-led and phenotype-based approach for virtual gene panel generation for analysis of targeted CES in patients with rare disease in a single institution. METHODS: Retrospective survey of 400 consecutive cases presumed by clinicians to have rare monogenic disorders, referred on singleton basis for targeted CES. We evaluated diagnostic yield and variant workload to characterise the usefulness of a clinician-led approach for generation of virtual gene panels that can incorporate up to three different phenotype-driven gene selection methods. RESULTS: Abnormalities of the nervous system (54.5%), including intellectual disability, head and neck (19%), skeletal system (16%), ear (15%) and eye (15%) were the most common clinical features reported in referrals. Combined phenotype-driven strategies for virtual gene panel generation were used in 57% of cases. On average, 7.3 variants (median=5) per case were retained for clinical interpretation. The overall diagnostic rate of proband-only CES using personalised phenotype-driven virtual gene panels was 24%. CONCLUSIONS: Our results show that personalised virtual gene panels are a cost-effective approach for variant analysis of CES, maintaining diagnostic yield and optimising the use of resources for clinical genomic sequencing in the clinic.

Acute paediatric mastoiditis in the UK before and during the COVID-19 pandemic: A national observational study.

OBJECTIVES: To explore the impact of COVID-19 on the management and outcomes of acute paediatric mastoiditis across the UK. DESIGN: National retrospective and prospective audit. SETTING: 48 UK secondary care ENT departments. PARTICIPANTS: Consecutive children aged 18 years or under, referred to ENT with a clinical diagnosis of mastoiditis. MAIN OUTCOME MEASURES: Cases were divided into Period 1 (01/11/19-15/03/20), before the UK population were instructed to reduce social contact, and Period 2 (16/03/20-30/04/21), following this. Periods 1 and 2 were compared for population variables, management and outcomes. Secondary analyses compared outcomes by primary treatment (medical/needle aspiration/surgical). RESULTS: 286 cases met criteria (median 4 per site, range 0-24). 9.4 cases were recorded per week in period 1 versus 2.0 in period 2, with no winter increase in cases in December 2020-Febraury 2021. Patient age differed between periods 1 and 2 (3.2 vs 4.7 years respectively, p < 0.001). 85% of children in period 2 were tested for COVID-19 with a single positive test. In period, 2 cases associated with P. aeruginosa significantly increased. 48.6% of children were scanned in period 1 vs 41.1% in period 2. Surgical management was used more frequently in period 1 (43.0% vs 24.3%, p = 0.001). Treatment success was high, with failure of initial management in 6.3%, and 30-day re-admission for recurrence in 2.1%. The adverse event rate (15.7% overall) did not vary by treatment modality or between periods 1& 2. CONCLUSION: The COVID-19 pandemic led to a significant change in the presentation and case mix of acute paediatric mastoiditis in the UK.

How are trial outcomes prioritised by stakeholders from different regions? Analysis of an international Delphi survey to develop a core outcome set in gastric cancer surgery.

BACKGROUND: International stakeholder participation is important in the development of core outcome sets (COS). Stakeholders from varying regions may value health outcomes differently. Here, we explore how region, health income and participant characteristics influence prioritisation of outcomes during development of a COS for gastric cancer surgery trials (the GASTROS study). METHODS: 952 participants from 55 countries participating in a Delphi survey during COS development were eligible for inclusion. Recruits were grouped according to region (East or West), country income classification (high and low-to-middle income) and other characteristics (e.g. patients; age, sex, time since surgery, mode of treatment, surgical approach and healthcare professionals; clinical experience). Groups were compared with respect to how they categorised 56 outcomes identified as potentially important to include in the final COS ('consensus in', 'consensus out', 'no consensus'). Outcomes categorised as 'consensus in' or 'consensus out' by all 3 stakeholder groups would be automatically included in or excluded from the COS respectively. RESULTS: In total, 13 outcomes were categorised 'consensus in' (disease-free survival, disease-specific survival, surgery-related death, recurrence of cancer, completeness of tumour removal, overall quality of life, nutritional effects, all-cause complications, intraoperative complications, anaesthetic complications, anastomotic complications, multiple organ failure, and bleeding), 13 'consensus out' and 31 'no consensus'. There was little variation in prioritisation of outcomes by stakeholders from Eastern or Western countries and high or low-to-middle income countries. There was little variation in outcome prioritisation within either health professional or patient groups. CONCLUSION: Our study suggests that there is little variation in opinion within stakeholder groups when participant region and other characteristics are considered. This finding may help COS developers when designing their Delphi surveys and recruitment strategies. Further work across other clinical fields is needed before broad recommendations can be made.