Retrospective observational study analysing the trends in ventilation tube insertion in children in Scotland between 2001 and 2018.

OBJECTIVES: Otitis media with effusion (OME) is common, affecting up to 90% of children. Around 25% will have a persistent effusion with conductive hearing loss which can impact their development. Ventilation tubes (VTs) can improve their hearing in the short term. This study aims to analyse the trends in VT insertion rates across Scotland. DESIGN: Retrospective observational study. SETTING: All mainland Scottish health boards. PARTICIPANTS: All children aged 0-16 who underwent a VT insertion procedure from 2001 to 2018 were included. MAIN OUTCOME MEASURES: Data were provided by the Scottish Public Health Observatory, using Scottish Morbidity Records. Mid-year population estimates were obtained from the National Records Office of Scotland. Socioeconomic deprivation was estimated based on area of residence using the Scottish Index of Multiple Deprivation. VT insertion rates were calculated and trends analysed. RESULTS: A total of 35 878 VT procedures were performed in total with a mean rate of 2.02 per 1000 children per year. The highest insertion rates were observed in children aged 4-6. VT insertion rates reduced during the study period (R = -0.729, p = .001). Variability in VT insertion rates between health boards reduced. There was a significant association between socioeconomic deprivation and VT insertion rate, with the most deprived children having the highest rate (p < .001). CONCLUSIONS: VT insertion rates and the variability between Scottish health boards have reduced over the past two decades, suggesting a more equitable system. Our data intimates that the decision to perform VT insertion is based upon disease prevalence rather than clinician preference.

The role of liquid biopsy in management of the neck with indeterminate response on post-treatment imaging following non-surgical management of oropharyngeal cancer.

INTRODUCTION: This study aimed to determine if post-treatment HPV cell-free DNA (cfDNA) can assist in the decision-making process for salvage neck dissection in patients following non-surgical treatment of oropharyngeal squamous cell carcinoma (OPSCC) with a partial response in the neck on imaging at 12 weeks post-treatment. METHODS: 86 patients who completed treatment were prospectively recruited through the regional multidisciplinary team (MDT). Treatment response was categorised as complete response (CR), partial response (PR) or progressive disease on 12-week post-treatment imaging. Pre- and post-treatment blood samples were assessed for HPV cfDNA through droplet digital PCR (ddPCR). RESULTS: Eight patients had an isolated partial response in the neck. One (12.5%) had detectable HPV cfDNA (22.96 copies/ml) at ∼12 weeks post-treatment with positive disease on subsequent neck dissection (positive predictive value; PPV = 100%). Of the seven patients with undetectable HPV cfDNA, two patients had evidence of regional disease recurrence at 23.9 and 27.4 months respectively (negative predictive value; NPV = 71%). CONCLUSION: The detection of HPV cfDNA may help target salvage therapy in patients with a partial response in the neck. Follow-up studies in larger cohorts would be required to further validate the use of post-treatment HPV cfDNA in the management of OPSCC.

Longitudinal measurement of HPV copy number in cell-free DNA is associated with patient outcomes in HPV-positive oropharyngeal cancer.

INTRODUCTION: Oropharyngeal squamous cell carcinoma (OPSCC) is increasing in global prevalence and is divided into two types dependent on association with human papillomavirus (HPV). Assay of HPV copy number in plasma cell-free DNA (cfDNA) provides a minimally invasive method for detecting and monitoring tumour-derived HPV, with potential for enhancing clinical care. MATERIALS AND METHODS: In a prospectively recruited cohort of 104 OPSCC patients, we evaluate the utility of cfDNA droplet digital PCR (ddPCR) as a method for characterisation and longitudinal monitoring of patients with OPSCC. RESULTS: ddPCR assay of pre-treatment plasma cfDNA for five HPV types showed overall 95% concordance with p16 immunohistochemistry and PCR analysis of tumour tissue. Longitudinal sampling in 48 HPV+ve patients, with median follow-up of 20 months, was strongly associated with patient outcomes. Persistently elevated cfDNA-HPV post-treatment was associated with treatment failure (2/2 patients) and an increase of cfDNA-HPV in patients whose HPV levels were initially undetectable post-treatment was associated with disease recurrence (5/6 patients). No recurrence was observed in patients in whom cfDNA-HPV was undetectable in all post-treatment samples. In two patients, sequential HPV measurement could have avoided surgical intervention which did not confirm recurrence. CONCLUSION: The high concordance of pre-treatment plasma cfDNA-HPV analysis with tissue-based assays, together with the clinical associations of sequentially measured post-treatment cfDNA-HPV copy number add to a growing body of evidence that suggest utility of cfDNA-HPV ddPCR in management of OPSCC. Standardised clinical trials based on these data are now needed to assess the impact of such testing on overall patient outcomes.

Training and Transfer Effect of FluoroSim, an Augmented Reality Fluoroscopic Simulator for Dynamic Hip Screw Guidewire Insertion: A Single-Blinded Randomized Controlled Trial.

BACKGROUND: FluoroSim, a novel fluoroscopic simulator, can be used to practice dynamic hip screw (DHS) guidewire insertion in a high-fidelity clinical scenario. Our aim was to demonstrate a training effect in undergraduate medical students who are not familiar with this operation and its simulation. METHODS: Forty-five undergraduate medical students were recruited and randomized to either training (n = 23) or control (n = 22) cohorts. The training cohort had more exposure to FluoroSim (5 attempts each week) over a 2-week period (with a 1-week washout period in between) compared with the control cohort (a single attempt 1 week apart) over a 2-week period. Five real-time objective performance metrics were recorded: (1) tip-apex distance (TAD) (mm), (2) predicted cut-out rate (%), (3) total procedural time (sec), (4) total number of radiographs (n), and (5) total number of guidewire retries (n). RESULTS: At baseline, there was no significant difference in the performance metrics, which confirmed the absence of a selection bias. The intragroup training effect demonstrated a significant improvement in all metrics for the training cohort only. A significant difference between groups was demonstrated as the training cohort significantly outperformed the control cohort in 3 metrics (procedural time [25%], number of radiographs [57%], and number of guidewire retries [100%]; p < 0.001). A learning curve showed an inversely proportional correlation between frequency of attempts and procedural time as well as the number of digital fluoroscopic radiographs that were made, indicating the development of psychomotor skills. There was also an improved baseline of the learning curve after the 1-week washout period, suggesting skill retention. CONCLUSIONS: Skill acquisition with the FluoroSim system was demonstrated with repeat exposure in a safe, radiation-free high-fidelity clinical simulation with actual operating room equipment. The task of DHS guidewire insertion requires cognitive and psychomotor skills that take a variable number of attempts to acquire, as demonstrated on the learning curve. Additional work is required to demonstrate that the skill tested by the FluoroSim is the same skill that is required for intraoperative DHS guidewire insertion. However, use of the FluoroSim provides improvement in skills with extra-clinical training opportunities for orthopaedic trainees. CLINICAL RELEVANCE: FluoroSim has demonstrated validity and training effect. It has the potential to be approved for possible use on patients in the operating room to help surgeons with the operation. Consequently, operating time, accuracy of TAD, and surgical outcomes may all be improved.

Teaching basic trauma: validating FluoroSim, a digital fluoroscopic simulator for guide-wire insertion in hip surgery.

Background and purpose - Simulation is an adjunct to surgical education. However, nothing can accurately simulate fluoroscopic procedures in orthopedic trauma. Current options for training with fluoroscopy are either intraoperative, which risks radiation, or use of expensive and unrealistic virtual reality simulators. We introduce FluoroSim, an inexpensive digital fluoroscopy simulator without the need for radiation. Patients and methods - This was a multicenter study with 26 surgeons in which everyone completed 1 attempt at inserting a guide-wire into a femoral dry bone using surgical equipment and FluoroSim. 5 objective performance metrics were recorded in real-time to assess construct validity. The surgeons were categorized based on the number of dynamic hip screws (DHS) performed: novices (< 10), intermediates (10-39) and experts (≥ 40). A 7-point Likert scale questionnaire assessed the face and content validity of FluoroSim. Results - Construct validity was present for 2 clinically validated metrics in DHS surgery. Experts and intermediates statistically significantly outperformed novices for tip-apex distance and for cut-out rate. Novices took the least number of radiographs. Face and content validity were also observed. Interpretation - FluoroSim discriminated between novice and intermediate or expert surgeons based on tip-apex distance and cut-out rate while demonstrating face and content validity. FluoroSim provides a useful adjunct to orthopedic training. Our findings concur with results from studies using other simulation modalities. FluoroSim can be implemented for education easily and cheaply away from theater in a safe and controlled environment.