Transoral Robotic Surgery Using a Carbon Dioxide Flexible Laser for Tumors of the Upper Aerodigestive Tract

Objective: To determine the safety, feasibility, and efficacy of coupling transoral robotic technology with the flexible carbon dioxide (CO₂) laser for various tumors of the oropharynx and supraglottic larynx. Study Design: Prospective, pilot trial. Methods: Eight patients were enrolled in an IRB‐approved prospective trial for transoral robotic surgery with the aid of the flexible CO₂ laser. Results: Seven male patients with early carcinoma of the oropharynx or larynx successfully underwent tumor extirpation with the transoral robot and the flexible CO₂ laser. We were unable to gain access to the supraglottic larynx in one female patient. The final pathology revealed seven patients with squamous cell carcinoma and one patient with adenoid cystic carcinoma. The flexible CO₂ laser provided fine incisions with excellent hemostasis and minimal peripheral tissue injury. Additionally, the laser provided an excellent tool for raising pharyngeal flaps for reconstruction of the oropharynx. Conclusion: The flexible CO₂ laser offers a unique advantage of precise incisions and may provide a valuable tool for both tumor extirpation and the creation of flaps for transoral robotic reconstruction.     

Endemic prevalence of hepatitis B and C in Mongolia: A nationwide survey amongst Mongolian adults

In this study, a representative group of Mongolian adults was tested for hepatitis B virus (HBV) and hepatitis C virus (HCV). Screening was conducted at 17 different locations on a randomly sampled group, representing the Mongolian adult population. A total of 1158 adults, 500 (43.1%) men and 659 (56.9%) women were included. The prevalence estimates of HBV and HCV amongst the general Mongolian adult population were found to be 11.1%±1% (SE) and 8.5%±0.7% or 207 418 and 160 228 cases, respectively. For HCV, the majority of cases are concentrated in older age groups with a prevalence of 25.8% amongst those aged 50 years and above, whilst the prevalence of HBV does not vary significantly amongst age groups. For both, HBV and HCV, the data indicate a higher risk of infection and a higher mortality because of the hepatitis amongst men than amongst women. This study represents the first nationwide estimate of the prevalence of HBV in Mongolia and also considered the first for HCV since 2005 and confirm the position of Mongolia as one of the hot‐spots of chronic hepatitis infection in the world with about 19.4% of the adult population being infected with either HBV or HCV.     

Discrimination of Benign and Neoplastic Mucosa with a High-Resolution Microendoscope (HRME) in Head and Neck Cancer

Background

The efficacy of ablative surgery for head and neck squamous cell carcinoma (HNSCC) depends critically on obtaining negative margins. Although intraoperative ??frozen section?? analysis of margins is a valuable adjunct, it is expensive, time-consuming, and highly dependent on pathologist expertise. Optical imaging has potential to improve the accuracy of margins by identifying cancerous tissue in real time. Our goal was to determine the accuracy and inter-rater reliability of head and neck cancer specialists using high-resolution microendoscopic (HRME) images to discriminate between cancerous and benign mucosa.

Methods

Thirty-eight patients diagnosed with head and neck squamous cell carcinoma (HNSCC) were enrolled in this single-center study. HRME was used to image each specimen after application of proflavine, with concurrent standard histopathologic analysis. Images were evaluated for quality control, and a training set containing representative images of benign and neoplastic tissue was assembled. After viewing training images, seven head and neck cancer specialists with no previous HRME experience reviewed 36 test images and were asked to classify each.

Results

The mean accuracy of all reviewers in correctly diagnosing neoplastic mucosa was 97?% (95?% confidence interval (CI), 94?C99?%). The mean sensitivity and specificity were 98?% (97?C100?%) and 92?% (87?C98?%), respectively. The Fleiss kappa statistic for inter-rater reliability was 0.84 (0.77?C0.91).

Conclusions

Medical professionals can be quickly trained to use HRME to discriminate between benign and neoplastic mucosa in the head and neck. With further development, the HRME shows promise as a method of real-time margin determination at the point of care.     

Implementation of a 4-dimensional computed tomography protocol for parathyroid adenoma localization

PurposeTo present the results of our implementation of a four-dimensional computed tomography- (4DCT) based parathyroid localization protocol for primary hyperparathyroidism at a safety net hospital.MethodsWe performed a retrospective review of all patients who underwent parathyroidectomy for primary hyperparathyroidism at Elmhurst Hospital Center from June 2016 – September 2019. Patients treated prior to the implementation of 4DCT during October 2018 served as historical controls for comparison. Imaging-related costs and hospital charges were obtained from the Radiology Department for each patient.ResultsForty-two patients underwent parathyroid surgery during the study period. Twenty patients had undergone 4DCT while 22 had nuclear medicine studies with or without ultrasonography. The sensitivity and specificity of 4DCT was 90.4% and 100% respectively, compared to 63% and 93.7% for nuclear imaging studies and 41% and 95% for ultrasound. The mean number of glands explored was significantly less in the 4DCT group, 1.8 ± 1.19 versus 2.77 ± 1.26 (p = 0.01). There was no increase in infrastructure or personnel costs associated with 4DCT implementation.Conclusions4DCT represents an increasingly common imaging modality for pre-operative parathyroid localization. Here we demonstrate that 4DCT is associated with a reduction in the number of glands explored and enables minimally invasive parathyroid surgery. 4DCT is a cost-effective and clinically sound localization study for parathyroid localization in an urban safety-net hospital.