How far are we off? Analyzing the accuracy of surgical margin relocation in the head and neck.

BACKGROUND: Positive surgical margin rates remain high in head and neck cancer surgery. Relocation is challenging given the complex, three-dimensional (3D) anatomy. METHODS: Prospective, multi-institutional study to determine accuracy of head and neck surgeons and pathologists relocating margins on virtual 3D specimen models using written descriptions from pathology reports. Using 3D models of 10 head and neck surgical specimens, each participant relocated 20 mucosal margins (10 perpendicular, 10 shave). RESULTS: A total of 32 participants, 23 surgeons and 9 pathologists, marked 640 margins. Of the 320 marked perpendicular margins, 49.7% were greater than 1 centimeter from the true margin with a mean relocation error of 10.2 mm. Marked shave margins overlapped with the true margin a mean 54% of the time, with no overlap in 44 of 320 (13.8%) shave margins. CONCLUSIONS: Surgical margin relocation is imprecise and challenging even for experienced surgeons and pathologists. New communication technologies are needed.

Comparison of da Vinci Single Port vs Si Systems for Transoral Robotic-Assisted Surgery: A Review With Technical Insights.

Importance: Transoral robot-assisted surgery (TORS) continues to have a major role in the treatment of oropharyngeal cancer. As new iterations of robotic technology are increasingly utilized, it is important to share learning experiences and clinical outcomes data, to optimize technical efficiency and clinical care. Observations: This was a retrospective review of a large academic institution's initial clinical use of the da Vinci Single Port (SP) compared with the da Vinci Si (Si) system. A total of 205 TORS cases were reviewed: 109 in the SP group (November 22, 2018, through September 30, 2020), and 96 in the Si group (January 1, 2016, through November 12, 2018). Both groups had comparable operative times, rates of postoperative pharyngeal hemorrhage, length of hospital stay, and duration of nasogastric feeding tube use. There was no difference in pathological characteristics, rates of positive margins, or indications for or time to initiation of adjuvant therapy between the groups. The collective experience of 6 faculty members-who have trained 139 TORS surgeons for the SP system rollout-was compiled to provide a summary of learning experiences and technical notes on safe and efficient operation of the SP system. Conclusions and Relevance: This Review found that the functional and oncologic outcomes were comparable between TORS cases performed with the Si and SP systems, and they had similar complication rates. Recognized advantages of the SP over the Si system include the availability of bipolar-energized instruments, a usable third surgical arm, and improved camera image quality.

Complications following salvage transoral robotic surgery with and without reconstruction: A systematic review of the literature.

BACKGROUND: Transoral robotic surgery (TORS) has been used in the salvage setting for head and neck cancers both with and without reconstruction. The complications of salvage TORS and the effect of reconstruction on complications has not been studied. OBJECTIVE: To study the complications of salvage TORS and examine the effect of reconstruction on complication rates. METHOD: An electronic search of the English- language literature using PubMed, Medline, and the Cochrane database was conducted and a systematic review performed in accordance with PRISMA guidelines (CRD42020181057). RESULTS: A total of 23 studies including 533 patients have been published on salvage TORS.The average patient age was 61.2 years.Prior treatment was described for 420 patients.205 (48.8%) underwent prior definitive radiotherapy (RT).160 (38.1%) underwent definitive chemoradiotherapy (CRT).Only 55 (13.1%) had prior surgery.Overall, there were 158 complications with a pooled rate of 33.6% (95%CI: 25.4-42.3%).77 were major complications requiring surgical intervention with a pooled rate of 18.9% (95% CI: 14.8-23.3%).The number of patients undergoing reconstruction among salvage cases in the literature is 59 (9.19%), with 24 local flaps and 25 microvascular free flaps.Reconstruction was associated with lower overall hemorrhage rates but had no impact on major hemorrhage rates. CONCLUSIONS: The pooled incidence rates of major complications, major POH and emergency tracheostomy following salvage TORS are 18.9%, 10.5%, and 4.4%.The rate of death following salvage TORS is 3.6%. Reconstruction was associated with lower overall hemorrhage rate after salvage TORS but had no impact on major postoperative hemorrhage rates.

Adoption of otolaryngologist-head neck surgeons toward transoral robotic surgery: An international survey.

Objective: To investigate perception, adoption and awareness of otolaryngologist-head neck surgeons (OTO-HNS) toward transoral robotic surgery (TORS). Methods: An online survey was sent to 1383 OTO-HNS on the perception, adoption and awareness about TORS to members of many otolaryngological societies. The following aspects were assessed: TORS access; training; awareness/perception; indications and advantages/barriers to TORS practice. The responses were presented for the entire cohort and regarding the TORS experience of OTO-HNS. Results: A total of 359 completed the survey (26%); including 115 TORS surgeons. TORS-surgeons carry out a mean number of 34.4 annual TORS procedures. The primary barriers to TORS were the cost of the robot (74%) and disposable accessories (69%), and the lack of training opportunity (38%). The 3D view of the surgical field (66%), the postoperative quality of life outcomes (63%) and the shorter hospital stay (56%) were the most important benefits of TORS. TORS-surgeons believed more frequently that TORS is indicated for cT1-T2 oropharyngeal and supraglottic cancers than non-TORS surgeons (p < .005). Participants believed that the priorities for the future consisted of the reduction of the robot arm size and the incorporation of flexible instruments (28%); the integration of laser (25%) or GPS tracking based on imaging (18%), all of them to improve accesses to hypopharynx (24%), supraglottic larynx (23%) and vocal folds (22%). Conclusions: The perception, adoption and knowledges toward TORS depend on the access to robot. The findings of this survey may help guide decisions on how improve the dissemination of TORS interest and awareness.

Narrow-field supracricoid partial laryngectomy: Procedure development and initial clinical experiences.

OBJECTIVES: To evaluate the feasibility of narrow-field supracricoid partial laryngectomy with cricohyoidoepiglottopexy (NF-SCPL-CHEP). METHODS: Between 2019 and 2020, five patients with glottic cancers underwent NF-SCPL-CHEP. The mean durations of surgical drains, tracheostomy canula, and nasogastric tube use were evaluated. Length of stay following NF-SCPL-CHEP was compared with that of our open SCPL historical controls. A case summary is provided for the first patients, with detailed information about postoperative management and function. RESULTS: All five patients achieved uneventful postoperative recoveries without major complications. The average time for surgical drains, tracheostomy canula, and nasogastric tube use were 2, 15, and 46 days, respectively. The mean overall hospitalization period was 36 days for NF-SCPL-CHEP patients. The mean period of hospitalization based on our early experiences between 1997 and 2005 with classical open SCPL was 72 days. All patients were fully functional and local recurrences or distant metastases were not encountered during a mean observation period of 39 months. CONCLUSIONS: NF-SCPL-CHEP with 6 cm cervical access appeared technically feasible and oncologically sound in this initial clinical experience. An extra 2 cm incision, which enabled lateral neck dissection, was not felt to detract from the overall minimally invasive basis of NF-SCPL-CHEP. The clinical results were encouraging with limited complications and predictable postoperative recovery. The length of stay for patients undergoing NF-SCPL was half that of open SCPL historical controls. Less damages to local circulation may associate with the positive influences. Further study with a large patient sample across multiple institutions are needed to carefully evaluate long-term functional and oncological outcomes.

Minimally Invasive Surgery in the United States, 2022: Understanding Its Value Using New Datasets.

INTRODUCTION: While minimally invasive surgery (MIS) has transformed the treatment landscape of surgical care, its utilization is not well understood. The newly released Nationwide Ambulatory Surgery Sample allows for more accurate estimates of MIS volume in the United States-in combination with inpatient datasets. MATERIALS AND METHODS: Multiple nationwide databases from the Healthcare Cost and Utilization Project (HCUP) were used: the Nationwide Ambulatory Surgery Sample and National Inpatient Sample. The volume of MIS and robotic procedures were calculated from 2016 to 2018. An online query system, HCUPNet, was queried for inpatient stays from 1993 to 2014. RESULTS: In 2017, 9.8 million inpatient major operating room procedures were analyzed, of which 11.1% were MIS and 2.5% were robotic-assisted, compared with 9.6 million inpatient operating room procedures (11.2% MIS and 2.9% robotic-assisted) in 2018. There were 10.6, 10.6, and 10.7 million ambulatory procedures in 2016, 2017, and 2018, respectively. Ambulatory MIS procedures showed an increasing trend across years, representing 16.9%, 17.4%, and 18%, respectively. HCUPNet data revealed an increase in inpatient MIS cases from 529,811 (8.9%) in 1993 to 1,443,446 (20.7%) in 2014. CONCLUSIONS: This study is the first to estimate national MIS volume across specialties in both inpatient and ambulatory hospital settings. We found a trend toward a higher proportion of MIS and robotic cases from 1997 to 2018. These data may help contribute to a more comprehensive understanding of MIS value within surgery and highlight limitations of current databases, especially when categorizing robotic cases on a national scale.

Single-port robotic transcervical long-segment thoracic tracheal reconstruction: Cadaveric proof-of-concept study.

Objective: Slide tracheoplasty is the standard technique to repair congenital long-segment tracheal stenosis. This operation most commonly requires median sternotomy, which has drawbacks in young children. We hypothesized that a transcervical approach without sternotomy would be feasible if done with a single-port robotic system. Methods: This proof-of concept study was performed in 2 small adult cadavers using a single-port robotic surgical system via a small neck incision. Relevant information, including operative time and details of operative technique, were recorded. Results: Long-segment slide tracheoplasty was completed successfully in 2 cadavers using a small neck incision and a single-port robotic surgical system. Strengths and pitfalls of the technique were identified, including technical refinements from the first attempt to the second. Operative time for robotic mobilization, incision, and anastomosis of the trachea was comparable to standard open approaches. Conclusions: Small-incision transcervical slide tracheoplasty, assisted by a single-port surgical robotic system, is feasible in a human cadaver. More work is needed to determine safety and applicability in live patients, particularly in children.

The robotic-assisted extended "Sistrunk" approach for tumors of the upper aerodigestive tract with limited transoral access: First description of oncological and functional outcomes.

We report on the first clinical experience with the robotic-assisted extended "Sistrunk" approach (RESA) for access to constrained spaces of the upper aerodigestive tract. This prospective case cohort study include six patients that underwent RESA if transoral exposure could not be achieved. Three patients received previous radiation. Patients were postoperatively followed until week 16 for perioperative complications, surgical margins, and functional outcomes. In all patients RESA allowed adequate exposure and resection with negative margins. Three patients who underwent salvage surgery experienced a minor or intermediate grade postoperative bleeding. No patient developed a pharyngocutaneous fistula. Three patients recovered their swallowing to their preoperative status and the remaining three experienced an improvement. All patients experienced complete recovery of their voice. RESA has the potential to provide a new organ preservation approach for head and neck cancer (HNC) not amenable to transoral exposure and thus warrants further prospective clinical studies.

Aldehyde dehydrogenase 3A1 deficiency leads to mitochondrial dysfunction and impacts salivary gland stem cell phenotype.

Adult salivary stem/progenitor cells (SSPC) have an intrinsic property to self-renew in order to maintain tissue architecture and homeostasis. Adult salivary glands have been documented to harbor SSPC, which have been shown to play a vital role in the regeneration of the glandular structures postradiation damage. We have previously demonstrated that activation of aldehyde dehydrogenase 3A1 (ALDH3A1) after radiation reduced aldehyde accumulation in SSPC, leading to less apoptosis and improved salivary function. We subsequently found that sustained pharmacological ALDH3A1 activation is critical to enhance regeneration of murine submandibular gland after radiation damage. Further investigation shows that ALDH3A1 function is crucial for SSPC self-renewal and survival even in the absence of radiation stress. Salivary glands from Aldh3a1 -/- mice have fewer acinar structures than wildtype mice. ALDH3A1 deletion or pharmacological inhibition in SSPC leads to a decrease in mitochondrial DNA copy number, lower expression of mitochondrial specific genes and proteins, structural abnormalities, lower membrane potential, and reduced cellular respiration. Loss or inhibition of ALDH3A1 also elevates ROS levels, depletes glutathione pool, and accumulates ALDH3A1 substrate 4-hydroxynonenal (4-HNE, a lipid peroxidation product), leading to decreased survival of murine SSPC that can be rescued by treatment with 4-HNE specific carbonyl scavengers. Our data indicate that ALDH3A1 activity protects mitochondrial function and is important for the regeneration activity of SSPC. This knowledge will help to guide our translational strategy of applying ALDH3A1 activators in the clinic to prevent radiation-related hyposalivation in head and neck cancer patients.

Circulating tumor DNA in head and neck cancer: Early successes and future promise.

LAY SUMMARY: The genetic components (DNA) of human papillomavirus-related throat cancer (in the oropharynx) might be measured after surgery to help to predict whether treatment has been successful.

Soft robotic manipulator for intraoperative MRI-guided transoral laser microsurgery.

Magnetic resonance (MR) imaging (MRI) provides compelling features for the guidance of interventional procedures, including high-contrast soft tissue imaging, detailed visualization of physiological changes, and thermometry. Laser-based tumor ablation stands to benefit greatly from MRI guidance because 3D resection margins alongside thermal distributions can be evaluated in real time to protect critical structures while ensuring adequate resection margins. However, few studies have investigated the use of projection-based lasers like those for transoral laser microsurgery, potentially because dexterous laser steering is required at the ablation site, raising substantial challenges in the confined MRI bore and its strong magnetic field. Here, we propose an MR-safe soft robotic system for MRI-guided transoral laser microsurgery. Owing to its miniature size (Ø12 × 100 mm), inherent compliance, and five degrees of freedom, the soft robot ensures zero electromagnetic interference with MRI and enables safe and dexterous operation within the confined oral and pharyngeal cavities. The laser manipulator is rapidly fabricated with hybrid soft and hard structures and is powered by microvolume (<0.004 milliter) fluid flow to enable laser steering with enhanced stiffness and lowered hysteresis. A learning-based controller accommodates the inherent nonlinear robot actuation, which was validated with laser path-following tests. Submillimeter laser steering accuracy was demonstrated with a mean error < 0.20 mm. MRI compatibility testing demonstrated zero observable image artifacts during robot operation. Ex vivo tissue ablation and a cadaveric head-and-neck trial were carried out under MRI, where we employed MR thermometry to monitor the tissue ablation margin and thermal diffusion intraoperatively.

Using deep learning to identify the recurrent laryngeal nerve during thyroidectomy.

Surgeons must visually distinguish soft-tissues, such as nerves, from surrounding anatomy to prevent complications and optimize patient outcomes. An accurate nerve segmentation and analysis tool could provide useful insight for surgical decision-making. Here, we present an end-to-end, automatic deep learning computer vision algorithm to segment and measure nerves. Unlike traditional medical imaging, our unconstrained setup with accessible handheld digital cameras, along with the unstructured open surgery scene, makes this task uniquely challenging. We investigate one common procedure, thyroidectomy, during which surgeons must avoid damaging the recurrent laryngeal nerve (RLN), which is responsible for human speech. We evaluate our segmentation algorithm on a diverse dataset across varied and challenging settings of operating room image capture, and show strong segmentation performance in the optimal image capture condition. This work lays the foundation for future research in real-time tissue discrimination and integration of accessible, intelligent tools into open surgery to provide actionable insights.

Landscape of innate lymphoid cells in human head and neck cancer reveals divergent NK cell states in the tumor microenvironment.

Natural killer (NK) cells comprise one subset of the innate lymphoid cell (ILC) family. Despite reported antitumor functions of NK cells, their tangible contribution to tumor control in humans remains controversial. This is due to incomplete understanding of the NK cell states within the tumor microenvironment (TME). Here, we demonstrate that peripheral circulating NK cells differentiate down two divergent pathways within the TME, resulting in different end states. One resembles intraepithelial ILC1s (ieILC1) and possesses potent in vivo antitumor activity. The other expresses genes associated with immune hyporesponsiveness and has poor antitumor functional capacity. Interleukin-15 (IL-15) and direct contact between the tumor cells and NK cells are required for the differentiation into CD49a+CD103+ cells, resembling ieILC1s. These data explain the similarity between ieILC1s and tissue-resident NK cells, provide insight into the origin of ieILC1s, and identify the ieILC1-like cell state within the TME to be the NK cell phenotype with the greatest antitumor activity. Because the proportions of the different ILC states vary between tumors, these findings provide a resource for the clinical study of innate immune responses against tumors and the design of novel therapy.

Preoperative predictors of difficult oropharyngeal exposure for transoral robotic surgery: The Pharyngoscore.

BACKGROUND: Insufficient exposure may require termination of procedure in transoral robotic surgery (TORS). The aim of study was to develop a "Pharyngoscore" to quantify the risk of difficult oropharyngeal exposure (DOE) before TORS. METHODS: Three-hundred six patients undergoing any surgical procedure at one Academic Hospital were prospectively enrolled. Oropharynx was exposed with Feyh-Kastenbauer retractor. Exposure was evaluated by direct and endoscopic visualization of the four oropharyngeal subsites. Preoperative clinical/anthropometric parameters were studied in good oropharyngeal exposure and DOE groups. Logistic regression was performed to explore association between clinical/anthropometric parameters and DOE. Statistically significant parameters at multivariate analysis were incorporated into a nomogram. RESULTS: Sixty-five (21.2%) subjects were characterized by DOE. Variables associated with DOE at univariate analysis were male (p = 0.031), modified Mallampati Class (MMC) ≥ III (p < 0.001), smaller interincisor gap (p < 0.001), and larger neck circumference (p = 0.006). MMC, interincisor gap, and neck circumference were significant at multivariate analysis and were presented with a nomogram for creating the Pharyngoscore. CONCLUSIONS: The Pharyngoscore is a promising tool for calculating DOE probability before TORS.

Robotic transmaxillary approach to the lateral infratemporal fossa: A preclinical cadaveric study using a next-generation single-port robotic system.

Robotic transmaxillary skull base surgery has been described using multiport systems. This cadaveric study investigates the feasibility of transmaxillary skull base surgery using a next-generation robot. An extended Caldwell-Luc antrostomy, measuring 3.3 cm by 4.0 cm, was performed in 15 min using a Kerrison rongeur and the robotic endoscope. A single-port, robotic system (da Vinci Sp®, Intuitive Surgical, Inc, Sunnyvale, CA, USA) was then deployed throught the extended Caldwell-Luc approach and provided sufficient reach, visualization, and maneuverability to work within the pterygopalatine fossa (PPF) and the infratemporal fossa (ITF) using three surgical instruments. The ITF dissection was easiest with two instruments using the third instrument to retract the muscles of mastication. This study demonstrates the feasibility of single-port robotic transmaxillary approaches to the lateral ITF. Using a single-port robotic system, the operating surgeon can for the first time work in the PPF and ITF using two functional arms for tumor dissection and a third to retract.

Videomics: bringing deep learning to diagnostic endoscopy.

PURPOSE OF REVIEW: Machine learning (ML) algorithms have augmented human judgment in various fields of clinical medicine. However, little progress has been made in applying these tools to video-endoscopy. We reviewed the field of video-analysis (herein termed 'Videomics' for the first time) as applied to diagnostic endoscopy, assessing its preliminary findings, potential, as well as limitations, and consider future developments. RECENT FINDINGS: ML has been applied to diagnostic endoscopy with different aims: blind-spot detection, automatic quality control, lesion detection, classification, and characterization. The early experience in gastrointestinal endoscopy has recently been expanded to the upper aerodigestive tract, demonstrating promising results in both clinical fields. From top to bottom, multispectral imaging (such as Narrow Band Imaging) appeared to provide significant information drawn from endoscopic images. SUMMARY: Videomics is an emerging discipline that has the potential to significantly improve human detection and characterization of clinically significant lesions during endoscopy across medical and surgical disciplines. Research teams should focus on the standardization of data collection, identification of common targets, and optimal reporting. With such a collaborative stepwise approach, Videomics is likely to soon augment clinical endoscopy, significantly impacting cancer patient outcomes.

Verbalization, Categorization, and Evaluation of Fundamental Surgical Skills: An Expert Consensus in Open Head and Neck Surgery.

Objective: This study aimed to verbalize fundamental surgical skills required for open head and neck surgery (OHNS), to organize them by categorization, and to establish a consensus among surgeons regarding the importance and difficulty of each skill. Summary Background Data: Improvement of fundamental surgical skills is the core of surgical education; however, surgical skills are not yet organized, and consensus in any surgical field remains uncertain. Methods: Fundamental surgical skills during OHNS were collected from surgical textbooks, real surgeries, and expert interviews. The items were analyzed to calculate the frequency of words and were categorized by 2 expert surgeons. After consensus on the importance and difficulty of each item was established by 15 expert surgeons using a Delphi survey, principal component (PC) analysis was performed to integrate importance and difficulty into a single parameter. Results: Sixty skills were verbalized and categorized into 7 categories: "skin flap elevation (n = 6)," "vessel management (n = 9)," "nerve preservation (n = 8)," "instrument handling (n = 11)," "counter traction (n = 7)," "tissue exposure (n = 9)," and "flow and planning (n = 10)." In the Delphi survey, expert consensus was established after 2 voting rounds (Cronbach's α ≥ 0.80). The "counter traction" and "flow and planning" categories had high PC scores, which indicate priority in surgical education. Conclusion: Fundamental OHNS skills were verbalized, categorized, and evaluated via expert consensus. Assessment of surgeons' skills by the structured items hereby developed will help standardize the quality of OHNS and improve patient outcomes.