Electric Bioimpedance Sensing for the Detection of Head and Neck Squamous Cell Carcinoma

The early detection of head and neck squamous cell carcinoma (HNSCC) is essential to improve patient prognosis and enable organ and function preservation treatments. The objective of this study is to assess the feasibility of using electrical bioimpedance (EBI) sensing technology to detect HNSCC tissue. A prospective study was carried out analyzing tissue from 46 patients undergoing surgery for HNSCC. The goal was the correct identification of pathologic tissue using a novel needle-based EBI sensing device and AI-based classifiers. Considering the data from the overall patient cohort, the system achieved accuracies between 0.67 and 0.93 when tested on tissues from the mucosa, skin, muscle, lymph node, and cartilage. Furthermore, when considering a patient-specific setting, the accuracy range increased to values between 0.82 and 0.95. This indicates that more reliable results may be achieved when considering a tissue-specific and patient-specific tissue assessment approach. Overall, this study shows that EBI sensing may be a reliable technology to distinguish pathologic from healthy tissue in the head and neck region. This observation supports the continuation of this research on the clinical use of EBI-based devices for early detection and margin assessment of HNSCC.

Treatment of primary epiglottis collapse in OSA in adults with glossoepiglottopexy: a 5-year experience

Objective

To review our 5-year experience with a modified version of glossoepiglottopexy for treatment of obstructive sleep apnoea syndrome (OSA) in two hospitals.

Methods

A retrospective analysis was carried out on a cohort of adult patients affected by OSA suffering from primary collapse of the epiglottis who underwent a modified glossoepiglottopexy. All patients underwent drug-induced sleep endoscopy, polysomnographic and swallowing evaluation, and assessment with the Epworth Sleepiness Scale (ESS).

Results

Forty-nine patients were retrospectively evaluated. Both the apnoea-hypopnoea index (AHI) (median AHI_post-AHI_pre = -22.4 events/h; p < 0.001) and oxygen desaturation index (ODI) showed a significant postoperative decrease (median ODI_post-ODI_pre = -18 events/h; p < 0.001), as did hypoxaemia index (median T_{90% post}-T_{90% pre} = -5%; p < 0.001). The ESS questionnaire revealed a significant decrease in postoperative scores (median ESS_post-ESS_pre =- 9; p < 0.001). None of the patients developed postoperative dysphagia.

Conclusions

Our 5-year experience demonstrates that modified glossoepiglottopexy is a safe and reliable surgical technique for treatment of primary epiglottic collapse in OSA patients.

Deep Learning Applied to White Light and Narrow Band Imaging Videolaryngoscopy: Toward Real-Time Laryngeal Cancer Detection

OBJECTIVES

To assess a new application of artificial intelligence for real-time detection of laryngeal squamous cell carcinoma (LSCC) in both white light (WL) and narrow-band imaging (NBI) videolaryngoscopies based on the You-Only-Look-Once (YOLO) deep learning convolutional neural network (CNN).

STUDY DESIGN

Experimental study with retrospective data.

METHODS

Recorded videos of LSCC were retrospectively collected from in-office transnasal videoendoscopies and intraoperative rigid endoscopies. LSCC videoframes were extracted for training, validation, and testing of various YOLO models. Different techniques were used to enhance the image analysis: contrast limited adaptive histogram equalization, data augmentation techniques, and test time augmentation (TTA). The best-performing model was used to assess the automatic detection of LSCC in six videolaryngoscopies.

RESULTS

Two hundred and nineteen patients were retrospectively enrolled. A total of 624 LSCC videoframes were extracted. The YOLO models were trained after random distribution of images into a training set (82.6%), validation set (8.2%), and testing set (9.2%). Among the various models, the ensemble algorithm (YOLOv5s with YOLOv5m-TTA) achieved the best LSCC detection results, with performance metrics in par with the results reported by other state-of-the-art detection models: 0.66 Precision (positive predicted value), 0.62 Recall (sensitivity), and 0.63 mean Average Precision at 0.5 intersection over union. Tests on the six videolaryngoscopies demonstrated an average computation time per videoframe of 0.026 seconds. Three demonstration videos are provided.

CONCLUSION

This study identified a suitable CNN model for LSCC detection in WL and NBI videolaryngoscopies. Detection performances are highly promising. The limited complexity and quick computational times for LSCC detection make this model ideal for real-time processing.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

Quality of life after transoral CO2 laser posterior cordotomy with or without partial arytenoidectomy for bilateral adductor vocal cord paralysis

Objectives

Bilateral adductor vocal cord paralysis (BAVCP) is a rare and challenging condition whose main consequence is reduction of airway patency at the glottic level, often causing respiratory distress, while vocal function tends to remain almost normal. We investigated the effect of transoral glottal widening on quality of life and decannulation rates in patients affected by BAVCP.

Methods

We retrospectively evaluated patients affected by BAVCP and treated by transoral CO₂ posterior cordotomy with or without medial partial arytenoidectomy (PC ± MPA) at two referral centers. The primary outcome was change in quality of life, evaluated pre- and post-operatively by the ADVS, VHI-30, and EAT-10 questionnaires. Secondary outcomes were the need for retreatments and, for patients with tracheotomy, the time to decannulation.

Results

Thirty-three patients met selection criteria. The etiology was post-surgical in 27 cases (81.8%), idiopathic in 4 (12.1%), a trauma-related in 1 (6.0%), and to other causes in 1 (3.0%). In 22 cases (66.7%), PC was combined with MPA. A significant improvement in responses for the ADVS (p < .0001) and EAT-10 (p < .0001) was observed, whereas the VHI-30 score did not change significantly post-operatively. All nine patients with a tracheostomy were successfully decannulated within 18 months after the surgical procedure.

Conclusions

For patients affected by BAVCP, PC ± MPA by transoral CO₂ laser microsurgery is a safe, customizable and minimally invasive treatment that can guarantee an affordable balance between quality of life in terms of phonation and swallowing and acceptable airway patency.

Modified full-face snorkeling mask for thoracic surgery and otolaryngology surgical use: comfort and usability assessment during the COVID-19 pandemic

Background:

A worldwide personal protection equipment (PPE) shortage has emerged during COVID-19 pandemic, contributing to the high incidence of SARS-CoV-2 infection among health care providers. To address this lack of PEE, new solutions have been researched. Among those, full-face snorkeling masks demonstrated to be an interesting option. Among surgical specialties otolaryngologists and thoracic surgeons are at high risk of infection, due to the close contact with airway secretions.

Objectives:

We tested the comfort and usability of a modified full-face snorkeling mask (Ocean Reef Mask Aria QR+) as a protective device for otolaryngologic and thoracic surgeries.

Methods:

The mask was customized with a 3D-printed adaptor supporting many industrial filter types, including FFP3 and heat and moisture exchangers (HME). We evaluated surgical performances of the mask, both subjectively, with a questionnaire filled in by the surgeons, as well as objectively, monitoring transcutaneous PCO₂ and PO₂ values of surgeons during surgical procedures.

Results:

The modified full-face snorkeling mask was tested during 9 otolaryngologic and 15 thoracic surgery procedures. The device demonstrated very good overall vision quality with some limitations regarding lateral vision and almost no difficulties in usability. Water condensation into the mask was absent in almost every case. Both PO₂ and PCO₂ parameters remained within normal ranges during every procedure.

Discussion:

The modified full-face snorkeling mask can be an innovative PPE. In the current COVID-19 pandemic scenario, the worldwide shortage of protective masks and goggles may exploit this ready-to-use and low-cost solution, especially for high-risk surgical procedures.

Validation of the European Laryngological Society classification of glottic vascular changes as seen by narrow band imaging in the optical biopsy setting

Purpose

In 2016, the European Laryngological Society (ELS) proposed a classification for vascular changes occurring in glottic lesions as visible by narrow band imaging (NBI), based on the dichotomic distinction between longitudinal vessels (not suspicious) and perpendicular ones (suspicious). The aim of our study was to validate this classification assessing the interobserver agreement and diagnostic test performance in detecting the final histopathology.

Methods

A retrospective study was carried out by reviewing clinical charts, preoperative videos, and final pathologic diagnosis of patients submitted to transoral microsurgery for laryngeal lesions in two Italian referral centers. In each institution, two physicians, independently re-assessed each case applying the ELS classification.

Results

The cohort was composed of 707 patients. The pathologic report showed benign lesions in 208 (29.5%) cases, papillomatosis in 34 (4.8%), squamous intraepithelial neoplasia (SIN) up to carcinoma in situ in 200 (28.2%), and squamous cell carcinoma (SCC) in 265 (37.5%). The interobserver agreement was extremely high in both institutions (k = 0.954, p < 0.001 and k = 0.880, p < 0.001). Considering the diagnostic performance for identification of at least SIN or SCC, the sensitivity was 0.804 and 0.902, the specificity 0.793 and 0.581, the positive predictive value 0.882 and 0.564, and the negative predictive value 0.678 and 0.908, respectively.

Conclusion

The ELS classification for NBI vascular changes of glottic lesions is a highly reliable tool whose systematic use allows a better diagnostic evaluation of suspicious laryngeal lesions, reliably distinguishing benign ones from those with a diagnosis of papillomatosis, SIN or SCC, thus paving the way towards confirmation of the optical biopsy concept.

Office-based procedures in laryngology

Objective

Development of transnasal fiberoptic laryngoscopy, integration of an operative channel (OC), the advent of high-definition television imaging, with improvements in laser technology, cleared the way for office-based laryngology. Three treatment categories can be identified: bioendoscopy-guided biopsy; laryngeal injection; laser-assisted surgery.

Methods

26 patients underwent OBPs at the Otolaryngology Clinic of IRCCS Policlinico San Martino, Genoa, Italy. Sixty-eight procedures were performed: 60 for recurrent respiratory papillomatosis (RRP), 5 for unilateral vocal fold paralysis (UVFP) and 3 for glottic leukoplakias. Neoblucaine 5% was administrated through the operative channel, for local anaesthesia. All procedures were carried out with the physician standing behind the patient. Narrow band imaging (NBI – Olympus Medical) or i-scan (Pentax Medical) were used to enhance the accuracy of the biopsy thanks to identification of atypical vascular patterns. Laryngeal injections were made using a 25G flexible needle. Opera Evo (Quanta system IEC/EN 60825-1:2007) is a hybrid fibre laser that is used for “blanching” and vaporisation of RRP lesions and to treat selected leukoplakias that were previously biopsied.

Conclusions

No major complications occurred during the procedures.

Overview of different modified full-face snorkelling masks for intraoperative protection

OBJECTIVE

The COVID-19 pandemic has caused significant impact on healthcare systems worldwide. The rate of infected healthcare workers is > 10% in Italy. Within this dramatic scenario, the development of new personal protective equipment (PPE) devices is mandatory. This study focuses on validation of modified full-face snorkel masks (MFFSM) as safe and protective equipment against SARS-CoV-2 infection during diagnostic and therapeutic procedures on the upper aerodigestive tract.

METHODS

Five different MFFSM were tested during otolaryngological surgery and in anaesthesia procedures. Data were collected through an online survey to assess the feedback of operators. pO2 and pCO2 monitoring values during procedures were recorded in selected cases.

RESULTS

All five MFFSM tested were easy to use and gave all operators a sound "feeling" of protection. All clinicians involved had common agreement regarding safety and the user-friendly format.

CONCLUSIONS

In the future, specific development of different type of masks for protection in the operating room, intensive care units and/or office will be possible as a joint venture between clinicians and developers. Goals for clinicians include better definition of needs and priorities, while developers can devote their expertise to produce devices that meet medical requirements.

SmartProbe: a bioimpedance sensing system for head and neck cancer tissue detection

OBJECTIVES

This study presents SmartProbe, an electrical bioimpedance (EBI) sensing system based on a concentric needle electrode (CNE). The system allows the use of commercial CNEs for accurate EBI measurement, and was specially developed for in-vivo real-time cancer detection.

APPROACH

Considering the uncertainties in EBI measurements due to the CNE manufacturing tolerances, we propose a calibration method based on statistical learning. This is done by extracting the correlation between the measured impedance value |Z|, and the material conductivity σ, for a group of reference materials. By utilizing this correlation, the relationship of σ and |Z| can be described as a function and reconstructed using a single measurement on a reference material of known conductivity.

MAIN RESULTS

This method simplifies the calibration process, and is verified experimentally. Its effectiveness is demonstrate by results that show less than 6% relative error. An additional experiment is conducted for evaluating the system's capability to detect cancerous tissue. Four types of ex-vivo human tissue from the head and neck region, including mucosa, muscle, cartilage and salivary gland, are characterized using SmartProbe. The measurements include both cancer and surrounding healthy tissue excised from 10 different patients operated on for head and neck cancer. The measured data is then processed using dimension reduction and analyzed for tissue classification. The final results show significant differences between pathologic and healthy tissues in muscle, mucosa and cartilage specimens.

SIGNIFICANCE

These results are highly promising and indicate a great potential for SmartProbe to be used in various cancer detection tasks.

Outcome predictors for non-resective pharyngoplasty alone or as a part of multilevel surgery, in obstructive sleep apnea-hypopnea syndrome

PURPOSE

Non-resective pharyngoplasty techniques have been shown to be effective to treat oropharyngeal collapse in patients affected by obstructive sleep apnea-hypopnea syndrome (OSAHS). The aim of our study is to evaluate outcome predictors in a cohort of patients affected by OSAHS and treated with non-resective pharyngoplasty, including variation of pharyngeal measures at the end of the surgical procedure.

METHODS

A cohort of patients affected by OSAHS, with palatal or lateral pharyngeal wall collapse, who underwent non-resective pharyngoplasty, were enrolled between 2014 and 2017. Surgical procedures encompassed non-resective pharyngoplasty by expansion sphincter pharyngoplasty (ESP) or barbed antero-lateral pharyngoplasty with barbed reposition pharyngoplasty (BRP) or barbed suspension pharyngoplasty (BSP) techniques, eventually associated with nasal surgery. Pharyngeal measures were recorded intraoperatively and their variation at the end of the procedure was considered. Surgical success was evaluated at least 6 months after surgery with respiratory polygraphy and ESS questionnaire. Outcome predictors were examined by multivariable logistic regression and ROC curve analysis.

RESULTS

Seventy patients met the study inclusion criteria. ESP, BRP, and BSP in a uni-/multilevel setting led to significant improvement of all respiratory polygraphic parameters and daily sleepiness (p < 0.0001). Outcome analysis showed that greater variation of antero-posterior pharyngeal measure was associated with success (p = 0.01), with an optimal cutoff value of 8.5 mm; low AHI_pre, high ESS_pre, and antero-lateral pharyngoplasty with barbed sutures were associated with a higher rate of cure (p < 0.05).

CONCLUSIONS

Non-resective pharyngoplasty is effective in treating OSAHS patients affected by palatal or lateral pharyngeal wall collapse, and intraoperative variation of antero-posterior width may be a useful tool to predict surgical success.

Barbed suspension pharyngoplasty for treatment of lateral pharyngeal wall and palatal collapse in patients affected by OSAHS

PURPOSE

The aim of this study is to analyze the efficacy of a new modified pharyngoplasty technique with barbed sutures: barbed suspension pharyngoplasty (BSP).

METHODS

We enrolled patients affected by obstructive sleep apnea-hypopnea syndrome (OSAHS), having the main site of obstruction at the palatal and lateral pharyngeal walls, who refused or failed to tolerate CPAP therapy and underwent non-resective pharyngoplasty with barbed sutures between January 2014 and October 2017. Two surgical techniques with barbed sutures were used: barbed reposition pharyngoplasty (BRP) and BSP; the main characteristics of the latter are a double passage of the needle, each side, through the soft palate.

RESULTS

Forty-two patients met the study inclusion criteria and were included in the analysis. Twenty-two patients underwent BRP and 20 BSP. Patients treated with both BRP and BSP achieved significant improvement in polysomnographic parameters: AHI, ODI, t90%, and daily sleepiness tested by the ESS questionnaire (p < 0.001). There were no significant differences between groups considering gender, age, or severity of OSAHS (p > 0.05). Outcomes were also comparable (p = 0.10) in the two groups; patients who underwent BSP had successful treatment in 100% of cases, compared to 86% with BRP, with a cure rate of 40% vs. 18%.

CONCLUSIONS

BSP is a novel surgical technique that is effective in treating oropharyngeal collapse and can be tailored for patients with high collapsibility of the soft palate who might benefit from the palatal stiffness given by multiple passages of the suture inside it.