Cutting Edge: SARS-CoV-2 Infection Induces Robust Germinal Center Activity in the Human Tonsil.

Understanding the generation of immunity to SARS-CoV-2 in lymphoid tissues draining the site of infection has implications for immunity to SARS-CoV-2. We performed tonsil biopsies under local anesthesia in 19 subjects who had recovered from SARS-CoV-2 infection 24-225 d previously. The biopsies yielded >3 million cells for flow cytometric analysis in 17 subjects. Total and SARS-CoV-2 spike-specific germinal center B cells, and T follicular helper cells, were readily detectable in human tonsils early after SARS-CoV-2 infection, as assessed by flow cytometry. Responses were higher in samples within 2 mo of infection but still detectable in some subjects out to 7 mo following infection. We conclude the tonsils are a secondary lymphoid organ that develop germinal center responses to SARS-CoV-2 infection and could play a role in the long-term development of immunity.

Optimising Patient Outcomes in Tongue Cancer: A Multidisciplinary Approach.

A multidisciplinary approach to the management of tongue cancer is vital for achieving optimal patient outcomes. Nursing and allied health professionals play essential roles within the team. We developed symposia comprising a series of online lectures offering a detailed perspective on the role each discipline and consumer perspective has in the management of patients with tongue cancer. The topics, including epidemiology and prevention, diagnosis, treatment planning, surgery, adjuvant care, and the management of recurrent or metastatic disease, were thoroughly examined. The symposia highlighted the significance of fostering collaboration and continuous learning through a multidisciplinary approach. This initiative should be relevant to healthcare professionals, researchers, and policymakers striving to enhance patient outcomes in tongue cancer care through innovative collaboration.

Surgeons blinded by enhanced navigation: the effect of augmented reality on attention.

BACKGROUND: Advanced image-guidance systems allowing presentation of three-dimensional navigational data in real time are being developed enthusiastically for many medical procedures. Other industries, including aviation and the military, have noted that shifting attention toward such compelling assistance has detrimental effects. Using the detection rate of unexpected findings, we assess whether inattentional blindness is significant in a surgical context and evaluate the impact of on-screen navigational cuing with augmented reality. METHODS: Surgeons and trainees performed an endoscopic navigation exercise on a cadaveric specimen. The subjects were randomized to either a standard endoscopic view (control) or an AR view consisting of an endoscopic video fused with anatomic contours. Two unexpected findings were presented in close proximity to the target point: one critical complication and one foreign body (screw). Task completion time, accuracy, and recognition of findings were recorded. RESULTS: Detection of the complication was 0/15 in the AR group versus 7/17 in the control group (p = 0.008). Detection of the screw was 1/15 (AR) and 7/17 (control) (p = 0.041). Recognition of either finding was 12/17 for the control group and 1/15 for the AR group (p < 0.001). Accuracy was greater for the AR group than for the control group, with the median distance from the target point measuring respectively 2.10 mm (interquartile range [IQR], 1.29-2.37) and 4.13 (IQR, 3.11-7.39) (p < 0.001). CONCLUSION: Inattentional blindness was evident in both groups. Although more accurate, the AR group was less likely to identify significant unexpected findings clearly within view. Advanced navigational displays may increase precision, but strategies to mitigate attentional costs need further investigation to allow safe implementation.

Synovial sarcoma of the pharynx causing airway obstruction.

This is the first reported Australian case of synovial sarcoma of the pharynx. A 29-year-old man had a large hypopharyngeal mass excised and received radiotherapy and chemotherapy. No recurrence was seen 12 months later.

Salvage transoral robotic surgery in early-stage oropharyngeal recurrence.

OBJECTIVES: Limited data are currently available regarding outcomes following transoral robotic surgery (TORS) in the salvage setting. This study aims to investigate the functional and oncological outcomes following TORS in salvage oropharyngeal tumors. STUDY DESIGN: All patients undergoing salvage TORS for a residual, recurrent, or new primary oropharyngeal squamous cell carcinoma within a previously radiated field between March 2014 and October 2018 were included. Patients undergoing salvage TORS for other subsites were excluded. Margin status, complication rates, long-term tracheostomy, and gastrostomy requirements and overall and disease-free survival outcomes were recorded. RESULTS: A total of 26 patients were included. Three patients (11%) experienced a TORS-specific major complication. A gastrostomy tube was required in 42% of patients on discharge (n = 11), and in 28% of patients on long-term follow-up (n = 7) at a median of 34 (interquartile range, 11.8-47.8) months. A tracheostomy was placed in 5 patients and all were removed before discharge. The 3-year overall survival and disease-free survival were 74% and 70%, respectively. CONCLUSION: Salvage TORS is a viable and effective option in the management of selected tumors within a previously radiated field.

Management of Parotid Metastatic Cutaneous Squamous Cell Carcinoma: Regional Recurrence Rates and Survival.

Objectives Extent of parotidectomy and neck dissection for metastatic cutaneous squamous cell carcinoma (cSCC) to the parotid is debated. We describe our experience, analyzing outcomes (overall survival and regional recurrence) associated with surgical extent and adjuvant treatment. Study Design A retrospective cohort study of parotidectomy with or without neck dissection for metastatic cSCC. Setting A tertiary referral cancer center in Australia. Subjects and Methods The study group consisted of patients with metastatic cSCC involving the parotid gland who underwent a curative-intent parotidectomy (superficial or total), with or without neck dissection, between 2003 and 2014. Demographic and clinical data, treatment modalities, and outcome parameters were collected from the electronic institutional database. Results Of 78 patients, 65 underwent superficial parotidectomy. Median follow-up was 6.5 years. Sixty-four patients (82%) patients received adjuvant radiotherapy. Cervical lymph nodes were involved in 6 (24%) elective neck dissections. Involved preauricular, facial, external jugular, and occipital nodes occurred in 36.9%. Adjuvant radiotherapy was associated with improved 5-year survival-50% (95% CI, 36%-69%) versus 20% (95% CI, 6%-70%)-and improved 2-year regional control: 89% (95% CI, 67%-100%) versus 40% (95% CI, 14%-100%). The ipsilateral parotid bed recurrence rate was 3.7% for those who received adjuvant radiotherapy and 27% for those who did not receive radiotherapy. Conclusion This study supports surgery plus adjuvant radiotherapy as a standard of care for metastatic cSCC. The low incidence of parotid bed recurrence with this approach suggests that routine elective deep lobe resection may not be required.

Unilateral radiotherapy treatment for p16/human papillomavirus-positive squamous cell carcinoma of unknown primary in the head and neck.

OBJECTIVES/HYPOTHESIS: The outcomes of unilateral radiotherapy treatment for patients with p16/HPV-positive squamous cell carcinomas of unknown primary (SCCUP) affecting cervical lymph nodes are under-reported. Compared to radiating large volumes of the pharyngeal axis (the more common approach), this is potentially a much less toxic treatment for a good prognosis group. STUDY DESIGN: Retrospective cohort study. METHODS: We identified patients with SCCUP who were treated radically at our center and did not have parotid or isolated level IV or V nodal involvement. Failure-free and overall survivals were calculated using Kaplan-Meier methods. RESULTS: From 2004 to 2012, there were 49 radically treated patients with SCCUP. Fourteen patients had bilateral neck treatment (they had bilateral nodal disease or suspected lesions in the base of tongue, though not proven with biopsy), two had surgery alone, whereas 33 had unilateral radiotherapy (after neck dissection, excisional biopsy, or definitively with concurrent chemotherapy). Of the 33 patients, 21 tested positive to p16/HPV and had median follow-up of 57 months. In this group, no isolated contralateral neck failures or putative primaries emerged. There was 1/21 (4.3%) ipsilateral neck failure, 1/21 (4.3%) concurrent contralateral neck and distant failure, and 1/21 (4.3%) patient with distant failure. The 5-year freedom from failure was 78% (95% confidence interval [CI]: 56%-100%) and overall survival was 90% (95% CI: 79%-100%). CONCLUSIONS: With no emergence of putative primaries and no isolated contralateral neck failures, this single-institution experience in p16/HPV-positive SCCUP patients suggests that unilateral radiotherapy may be an underutilized management strategy. LEVELS OF EVIDENCE: 4 Laryngoscope, 128:2076-2083, 2018.

Three-dimensional virtual navigation versus conventional image guidance: A randomized controlled trial.

OBJECTIVES/HYPOTHESIS: Providing image guidance in a 3-dimensional (3D) format, visually more in keeping with the operative field, could potentially reduce workload and lead to faster and more accurate navigation. We wished to assess a 3D virtual-view surgical navigation prototype in comparison to a traditional 2D system. METHODS: Thirty-seven otolaryngology surgeons and trainees completed a randomized crossover navigation exercise on a cadaver model. Each subject identified three sinonasal landmarks with 3D virtual (3DV) image guidance and three landmarks with conventional cross-sectional computed tomography (CT) image guidance. Subjects were randomized with regard to which side and display type was tested initially. Accuracy, task completion time, and task workload were recorded. RESULTS: Display type did not influence accuracy (P > 0.2) or efficiency (P > 0.3) for any of the six landmarks investigated. Pooled landmark data revealed a trend of improved accuracy in the 3DV group by 0.44 millimeters (95% confidence interval [0.00-0.88]). High-volume surgeons were significantly faster (P < 0.01) and had reduced workload scores in all domains (P < 0.01), but they were no more accurate (P > 0.28). CONCLUSION: Real-time 3D image guidance did not influence accuracy, efficiency, or task workload when compared to conventional triplanar image guidance. The subtle pooled accuracy advantage for the 3DV view is unlikely to be of clinical significance. Experience level was strongly correlated to task completion time and workload but did not influence accuracy. LEVEL OF EVIDENCE: N/A. Laryngoscope, 126:1510-1515, 2016.

Salvage surgery for locally recurrent oropharyngeal cancer.

BACKGROUND: There are limited data on whether recurrent human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (SCC) is associated with higher surgical salvage rates. The purpose of this study was to determine the success rate of salvage surgery for locally recurrent oropharyngeal cancer and factors influencing the outcome, including p16 status. METHODS: All patients who underwent salvage surgery for locally recurrent or persistent oropharyngeal cancer after (chemo)radiotherapy between 2000 and 2012 were included. The Kaplan-Meier analysis was used to determine overall survival (OS) and recurrence-free survival (RFS). Univariable analysis was performed using Cox proportional hazards regression. RESULTS: Thirty-four patients underwent salvage surgery. Five patients (14.7%) were tracheostomy dependent and 22 (64.7%) were gastrostomy tube dependent after salvage surgery. Postoperative complications occurred in 15 patients. RFS after salvage surgery was 28% and 19% at 3 and 5 years, respectively. The presence of nodal disease at the time of local recurrence, close or positive margins, and lymphovascular invasion were the only factors associated with worse survival on univariable analysis. HPV status based on p16 testing was not associated with either OS or RFS. CONCLUSION: Surgical salvage for oropharyngeal SCC after failure of radiotherapy (+/- chemotherapy) is feasible. Patients who may benefit from surgery include those without regional recurrence and/or those in whom negative margins can be obtained. However, patients may be tracheotomy or gastrostomy tube dependent. The p16 status did not seem to have prognostic impact in the salvage setting; however, larger series are required to assess this relationship. © 2015 Wiley Periodicals, Inc. Head Neck 38: E658-E664, 2016.

Augmented real-time navigation with critical structure proximity alerts for endoscopic skull base surgery.

OBJECTIVES/HYPOTHESIS: Image-guided surgery (IGS) systems are frequently utilized during cranial base surgery to aid in orientation and facilitate targeted surgery. We wished to assess the performance of our recently developed localized intraoperative virtual endoscopy (LIVE)-IGS prototype in a preclinical setting prior to deployment in the operating room. This system combines real-time ablative instrument tracking, critical structure proximity alerts, three-dimensional virtual endoscopic views, and intraoperative cone-beam computed tomographic image updates. STUDY DESIGN: Randomized-controlled trial plus qualitative analysis. METHODS: Skull base procedures were performed on 14 cadaver specimens by seven fellowship-trained skull base surgeons. Each subject performed two endoscopic transclival approaches; one with LIVE-IGS and one using a conventional IGS system in random order. National Aeronautics and Space Administration Task Load Index (NASA-TLX) scores were documented for each dissection, and a semistructured interview was recorded for qualitative assessment. RESULTS: The NASA-TLX scores for mental demand, effort, and frustration were significantly reduced with the LIVE-IGS system in comparison to conventional navigation (P < .05). The system interface was judged to be intuitive and most useful when there was a combination of high spatial demand, reduced or absent surface landmarks, and proximity to critical structures. The development of auditory icons for proximity alerts during the trial better informed the surgeon while limiting distraction. CONCLUSIONS: The LIVE-IGS system provided accurate, intuitive, and dynamic feedback to the operating surgeon. Further refinements to proximity alerts and visualization settings will enhance orientation while limiting distraction. The system is currently being deployed in a prospective clinical trial in skull base surgery.

Inattentional blindness increased with augmented reality surgical navigation.

BACKGROUND: Augmented reality (AR) surgical navigation systems, designed to increase accuracy and efficiency, have been shown to negatively impact on attention. We wished to assess the effect "head-up" AR displays have on attention, efficiency, and accuracy, while performing a surgical task, compared with the same information being presented on a submonitor (SM). METHODS: Fifty experienced otolaryngology surgeons (n = 42) and senior otolaryngology trainees (n = 8) performed an endoscopic surgical navigation exercise on a predissected cadaveric model. Computed tomography-generated anatomic contours were fused with the endoscopic image to provide an AR view. Subjects were randomized to perform the task with a standard endoscopic monitor with the AR navigation displayed on an SM or with AR as a single display. Accuracy, task completion time, and the recognition of unexpected findings (a foreign body and a critical complication) were recorded. RESULTS: Recognition of the foreign body was significantly better in the SM group (15/25 [60%]) compared with the AR alone group (8/25 [32%]; p = 0.02). There was no significant difference in task completion time (p = 0.83) or accuracy (p = 0.78) between the two groups. CONCLUSION: Providing identical surgical navigation on a SM, rather than on a single head-up display, reduced the level of inattentional blindness as measured by detection of unexpected findings. These gains were achieved without any measurable impact on efficiency or accuracy. AR displays may distract the user and we caution injudicious adoption of this technology for medical procedures.

Intraoperative cone-beam CT for head and neck surgery: feasibility of clinical implementation using a prototype mobile C-arm.

BACKGROUND: Intraoperative 3-dimensional (3D) imaging in head and neck surgery was developed using a prototype mobile C-arm for cone-beam CT (CBCT). This article summarizes its implementation in a prospective pilot and feasibility study. METHODS: The CBCT C-arm was used in 12 head and neck surgical oncology cases. Human-factors engineering methods and expert feedback from surgeons, nurses, and anesthetists were used to evaluate the impact of intraoperative imaging on the surgical environment and clinical workflow. Image quality of CBCT and the perceived clinical utility were evaluated. RESULTS: The CBCT C-arm was successfully incorporated in 12 head and neck cases and streamlined into the surgical environment. Reviewed 3D-CBCT images were qualitatively sufficient for intraoperative-guidance for bony detail. Additional artifact management is required to improve soft-tissue visualization. CONCLUSIONS: Intraoperative CBCT provides high-quality images for visualization of bony detail and is feasible during major head and neck surgery with acceptable workflow interruptions. Operations with significant bone ablation and/or reconstruction involving complex 3D anatomical structures are likely to benefit from the updated imaging.

The effect of augmented real-time image guidance on task workload during endoscopic sinus surgery.

BACKGROUND: Due to proximity to critical structures, the need for spatial awareness during endoscopic sinus surgery (ESS) is essential. We have developed an augmented, real-time image-guided surgery (ART-IGS) system that provides live navigational data and proximity alerts to the operating surgeon during ablation. We wished to test the hypothesis that task workload would be reduced when using this technology. METHODS: A trial involved 8 otolaryngology residents and fellows performing ESS on cadaveric specimens; 1 side in a conventional method (control) and 1 side with ART-IGS. After computed tomography scanning, anatomical contouring, and registration of the head, a three-dimensional (3D) virtual endoscopic view, ablative tool tracking, and proximity alerts were enabled. Each subject completed ESS tasks and rated their workload during and after the exercise using the National Aeronautics and Space Administration (NASA) Task Load Index (TLX). A questionnaire and open feedback interview were completed after the procedure. RESULTS: There was a significant reduction in mental demand, temporal demand, effort, and frustration when using the ART-IGS system in comparison to the control (p < 0.02). Perceived performance was increased (p = 0.02). Most subjects agreed that the system was sufficiently accurate, caused minimal interruption, and increased confidence. Optical tracking line-of-sight issues were frequently cited as the main limitation early in the study; however, this was largely resolved. CONCLUSION: ART-IGS reduces task workload for trainees performing ESS. Live navigation and alert zones may be a valuable intraoperative teaching aid.

Augmented image guidance improves skull base navigation and reduces task workload in trainees: a preclinical trial.

OBJECTIVES/HYPOTHESIS: Our group has developed an augmented image guidance system that incorporates intraoperative cone-beam computed tomography (CBCT), virtual or augmented displays, and image registration. We assessed the potential benefits of augmented endoscopy derived from this system for use during skull base navigation. Specifically, we wished to evaluate target localization accuracy and the effect on task workload and confidence. STUDY DESIGN: Prospective, sequential, paired preclinical trial. METHODS: A single cadaver head underwent computed tomography, and critical structures were contoured. The specimen was reimaged after endoscopic dissection and deformable registration allowed contours to be displayed on postablation CBCT imaging. A real-time virtual view including anatomical contours was provided parallel to the real endoscopic image. Twelve subjects were asked to endoscopically localize seven skull base landmarks in a conventional manner. The same exercise was then performed with augmented endoscopy. Precise three-dimensional (3D) localization was recorded with a tracked probe. The NASA task load index was completed after each exercise. A short questionnaire was also administered. RESULTS: The real-time augmented image guidance system aided localization in 85% of responses and increased confidence in 97%. There was a significant reduction in mental demand, effort, and frustration when the technology was employed, with an increase in perceived performance (P < .05). Three dimensional navigational precision was improved for all landmarks. CONCLUSIONS: Real-time augmented image-guided surgery increases accuracy and confidence in trainee surgeons and decreases task workload during skull base navigation. This technology shows great promise in assisting in skull base surgery even for experienced surgeons.

Preoxygenation is more effective in the 25 degrees head-up position than in the supine position in severely obese patients: a randomized controlled study.

BACKGROUND: Class III obese patients have altered respiratory mechanics, which are further impaired in the supine position. The authors explored the hypothesis that preoxygenation in the 25 degrees head-up position allows a greater safety margin for induction of anesthesia than the supine position. METHODS: A randomized controlled trial measured oxygen saturation and the desaturation safety period after 3 min of preoxygenation in 42 consecutive (male:female 13:29) severely obese (body mass index > 40 kg/m) patients who were undergoing laparoscopic adjustable gastric band surgery and were randomly assigned to the supine position or the 25 degrees head-up position. Serial arterial blood gases were taken before and after preoxygenation and 90 s after induction. After induction, ventilation was delayed until blood oxygen saturation reached 92%, and this desaturation safety period was recorded. RESULTS: The mean body mass indexes for the supine and 25 degrees head-up groups were 47.3 and 44.9 kg/m, respectively (P = 0.18). The group randomly assigned to the 25 degrees head-up position achieved higher preinduction oxygen tensions (442 +/- 104 vs. 360 +/- 99 mmHg; P = 0.012) and took longer to reach an oxygen saturation of 92% (201 +/- 55 vs. 155 +/- 69 s; P = 0.023). There was a strong positive correlation between the induction oxygen tension achieved and the time to reach an oxygen saturation of 92% (r = 0.51, P = 0.001). There were no adverse events associated with the study. CONCLUSION: Preoxygenation in the 25 degrees head-up position achieves 23% higher oxygen tensions, allowing a clinically significant increase in the desaturation safety period--greater time for intubation and airway control. Induction in the 25 degrees head-up position may provide a greater safety margin for airway control.