Combining a new CO2 laser wave guide with transoral robotic surgery: a feasibility study on four patients with malignant tumors

Preclinical implementation of a steerable, Da Vinci Xi® compatible CO2 -laser fibre carrier for transoral robotic surgery (TORS): A cadaveric feasibility study

INTRODUCTION

Monopolar electrocautery is the most common dissection and coagulation tool during transoral robotic surgery (TORS) but causes significant collateral tissue damage as opposed to CO₂ laser. We aimed at combining both modalities in one robotic instrument arm.

METHODS

We developed a steerable CO₂ -laser fibre carrier serving as an add-on to the existing Endowrist® monopolar spatula of the Da Vinci Xi. Feasibility and safety were assessed in a preclinical setting.

RESULTS

One radical tonsillectomy with monopolar cautery and three with the instrument prototype were performed in two cadavers by two surgeons. No serious prototype-related intra-operative difficulties were observed. Safe and efficient switching between energy sources proved possible in all simulated intra-operative bleeding events. Prototype use allowed for the identification of the majority of key anatomical structures and was scored favourably on NASA-TLX questionnaires.

DISCUSSION

The reported prototype successfully combines the advantages of CO₂ -laser with the advantages of TORS.

The CO2 waveguide laser with flexible fiber in transoral resection of oral and oropharyngeal cancers: a retrospective cohort study on postoperative and quality of life outcomes

The aim of this study was to evaluate the CO₂ waveguide laser (WG CO₂ laser) with flexible fiber (Lumenis Ltd., Yokneam, Israel) in the treatment of oral and oropharyngeal cancers, specifically focusing on postoperative outcomes, pain, and quality of life (QoL). Eighty-one patients, 43 women and 38 men, with oral or oropharyngeal cancer who consecutively underwent transoral resection by WG CO₂ laser from August 2015 to April 2020 were retrospectively enrolled. Resections were performed in super pulsed mode with a power setting ranging between 3 and 10 W. Data about frozen sections, reconstruction, complication rate, length of hospital stay, tracheostomy rate and time to decannulation, nasogastric feeding tube rate and time to oral feeding, pain, and QoL were reviewed. Continuous variables were presented as mean and standard deviation. Concordance between intraoperative frozen section examination and definitive histology was calculated using Cohen's K test of agreement. The mean length of hospital stay was 13 days. The feeding tube rate was 81%; the tracheostomy rate was 35%; the feeding tube was left in place for 8 days on average, and the time to decannulation was 9 days. The only complication was a postoperative bleeding in 4 patients. The median postoperative pain score measured by the Numeric Pain Rating Scale on postoperative days 1, 3, and 5 was 0 and there was a constant decrease in painkiller use over the days. The overall mean composite QoL score was 77 ± 14, with excellent results in saliva, taste, pain, and speech domains. Frozen section evaluation had a specificity of 99% and a negative predictive value of 98%. WG CO₂ laser is a good and safe tool for transoral tailored resection of oral and oropharyngeal cancers. It ensures a good overall QoL and guarantees fast recovery and a very low postoperative pain.

Comparison of transoral robotic surgery with other surgeries for obstructive sleep apnea

This study compared the characteristic surgical parameters and clinical effects of transoral robotic surgery (TORS) and other available methods used to alleviate obstructive sleep apnea. Articles on TORS and other surgeries for obstructive sleep apnea were identified in the PubMed and EMBASE databases. Two investigators independently reviewed the articles and classified the data for meta-analysis. The pooled effect sizes of TORS (standardized mean difference; SMD = − 2.38), coblation tongue base resection (CTBR; SMD = − 2.00) and upper airway stimulation (UAS; SMD = − 0.94) revealed significant improvement in the apnea–hypopnea index (AHI; p < 0.05). The lowest O₂ saturation reported was significantly increased following TORS (SMD = 1.43), CTBR (SMD = 0.86) and UAS (SMD = 1.24, p < 0.05). Furthermore, TORS (SMD = − 2.91) and CTBR (SMD = − 1.51, p < 0.05) significantly reduced the Epworth Sleepiness Scale (ESS) score. No significant difference in operation time, success rate, or instances of complication were observed between TORS and the other compared interventions. The use of TORS in obstructive sleep apnea has the same rate of success and failure as other methods of surgical intervention for obstructive sleep apnea with no statistical difference in operation times. The reported clinical effects on the AHI, lowest O₂ saturation, and ESS scores of TORS were similar to those of other surgeries.

Early glottic tumours with anterior commissure involvement. Literature review and consensus document. Head and Neck and Skull Base Commission, SEORL-CCC

The choice of the most appropriate treatment in early-stage glottic cancer with anterior commissure involvement remains controversial. Its therapeutic management is complex because it is a significant prognostic indicator of local control with 37% recurrence, due to the difficulty in establishing tumour extension with understaging of up to 40%, and due to the comparison of results in series on tumours that behave variably as they progress, such as T1a, T1b and T2a with commissure involvement. Furthermore, the complexity of the surgical approach using transoral CO2 laser microsurgery requires surgical skill, appropriate equipment and experience. Aspects to be reviewed in this document are: an updated anatomical definition of the anterior commissure, tumour progression based on histopathological studies, usefulness of videostroboscopy and NBI in diagnostic accuracy, validity of imaging tests, oncological results published in series reviews, systematic reviews and meta-analyses, tumour margin treatment and voice evaluation.Finally, by way of a summary, the document includes a series of recommendations for the treatment of these tumours.

Novel Energy Devices in Head and Neck Robotic Surgery - A Narrative Review

The advent of trans-oral robotic surgery (TORS) has facilitated removal of tumors previously deemed unresectable, by providing access to the deep structures of the head and neck. Despite this, the wider dissemination of TORS has been restricted due to issues with line of access, as the da Vinci robot was never designed with head and neck surgery in mind. Flexible instruments and novel energy delivery devices offer great potential in overcoming some of the existing challenges surrounding TORS. This review aimed to summarize the existing literature surrounding energy delivery in TORS and highlight areas of future innovation. MEDLINE was searched for studies relating to energy delivery in TORS in November 2019. The existing literature surrounding monopolar and bipolar electrocautery, LASER (CO₂, Tm:YAG and blue LASER), Ligasure and Harmonic was reviewed. Additionally, the latest iteration of the da Vinci; the SP, and the FLEX robot were evaluated as novel methods of energy delivery in TORS. Overall, these novel energy devices and robotic systems are predicted to further improve energy delivery to the head and neck. The use of flexible LASER in particular is well substantiated in the literature. This has the potential to achieve treatment de-escalation, based on the excellent outcomes demonstrated for disease-free margins and post-operative morbidity.

Transoral Robot-Assisted Surgery in Supraglottic and Oropharyngeal Squamous Cell Carcinoma: Laser Versus Monopolar Electrocautery

BACKGROUND

Monopolar electrocautery (EC) is the surgical cutting and haemostatic tool most commonly used for transoral robotic surgery (TORS). The aim of this study was to retrospectively compare EC efficacy in the treatment of patients affected by T1 or T2 oropharyngeal and supraglottic squamous cell carcinomas with the more recently introduced laser fibres.

METHODS

We considered all TORS patients admitted to our department from January 2010 to June 2019. The outcomes of patients treated with Thulium: yttrium aluminium garnet (YAG) laser (TY-TORS), CO₂ laser (CO₂-TORS) and EC (EC-TORS) were analysed in order to assess surgical performances, functional outcomes and postoperative complications.

RESULTS

Twenty patients satisfied the enrolling criteria, of which nine underwent laser-TORS, and the remaining 11 underwent EC-TORS. In all candidates, TORS procedures were completed without the need for microscopic/open conversion. Close or positive margins were significantly more frequent in EC-TORS (p = 0.028). A considerable difference was found in overall functional parameters: times of nasogastric tube and tracheostomy removal and time of hospital discharge were significantly shorter in laser-TORS (p = 0.04, p = 0.05, p = 0.04, respectively).

CONCLUSIONS

Laser-TORS showed better results in comparison with EC-TORS in term of tumour resection margins and patient functional outcomes. Our findings can be justified with the greater tissue thermal damage caused by EC-TORS, despite prospective randomized trials and increased patient numbers being needed to confirm these preliminary conclusions.

CO2 Transoral Laser Microsurgery in Benign, Premalignant and Malignant (Tis, T1, T2) Lesion of the Glottis. A Literature Review

Carbon Dioxide transoral laser microsurgery represents a reliable option for the treatment of early glottic carcinoma (Tis–T2), with good functional and oncological outcomes, nowadays representing one of the main options in larynx preservation protocols. The development and improvement of laser devices means surgeons are able to use more precise instruments compared with classic cold dissection in laser-assisted phonosurgery. Secondary effects on voice, swallowing, or quality of life as well as complications have been well documented. Also, with the introduction of a new proposal for staging systems following the principle of the three-dimensional map of isoprognostic zones, the use of narrow-band imaging in clinical evaluation and intraoperative, and the implementation of diffusion-weighted magnetic resonance during preoperative evaluation, the development of new tools to improve surgical quality and preliminary reports regarding the use of carbon dioxide laser in transoral robotic surgery suggests an exciting future for this technique.

How we improve the transoral resection for oral and oropharyngeal cancer: the CO2 waveguide laser

PURPOSE

The main aim of this study was to evaluate the CO₂ waveguide laser (CO₂ WGL) with flexible fiber (Lumenis, Santa Clara, CA) in the treatment of oral and oropharyngeal cancers specifically focusing on the lateral thermal damage (LTD) induced by this instrument and therefore on the reliability of the analysis of frozen sections collected during margin mapping.

METHODS

A total of 48 patients with oral and oropharyngeal cancers from T1 to T4a were prospectively enrolled in the study. We collected data about LTD, pathologic tumor and node stage (pTNM), surgical intervention, kind of reconstruction (no flap, local vs free flap), need for tracheotomy and time of removal, postoperative complications (such as bleeding, mucosal dehiscence, and fistula), need for feeding tube and time of removal.

RESULTS

Mean LTD was 164.7 ± 92.4 μm. Comparing frozen section histology before and after formalin embedding we found 5 true positives, 170 true negatives, 4 false positives and 4 false negatives, with a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 55.6%, 98%, 55.6%, 98%, and 96.1%, respectively.

CONCLUSION

CO₂ WGL is a very manageable tool, which allows a precise cut. However, its high costs, the inability to re-use the fibers and its low coagulation capability must be considered.

Intraoperative Margin Control in Transoral Approach for Oral and Oropharyngeal Cancer

OBJECTIVES

Piecemeal resection provides an innovative conceptual tool for margins surveillance because it entails the intraoperative evaluation of the whole resection margins and not just sample points, which should result in a better control of deep margins compared to en bloc resection. Although it is recognized that the intraoperative use of narrow band imaging (NBI) results in a better control of superficial margins, in this exploratory study we investigated whether NBI and piecemeal resection could be used in combination to improve margin control at both superficial and deep levels. Because piecemeal resection is based on frozen section analysis, we wanted to verify its reliability compared to definitive histological examination.

METHODS

The status of resection margins in a group of patients with oral and oropharyngeal cancers treated with NBI and laser CO2 piecemeal resection (group 1) was compared with that of an historical group of patients (group 2) treated with NBI and conventional en bloc resection. In group 1, sensitivity, specificity, and positive and negative predictive values were used to verify the rate of concordance between frozen section and definitive histology.

RESULTS

The difference between deep positive margins in the two groups was statistically significant (P = 0.042). The high sensitivity and specificity (94.6% and 94.7%, respectively) of frozen section analysis also demonstrated its reliability in the examination of larger samples corresponding to the whole margin.

CONCLUSION

Even if our findings are limited by the small number of patients, we are confident that the combined use of NBI and piecemeal resection could represent an attractive surgical strategy to improve margin control.

LEVEL OF EVIDENCE

2b Laryngoscope, 129:1810-1815, 2019.

Transoral surgery (TOS) in oropharyngeal cancer: Different tools, a single mini-invasive philosophy

Surgery with or without adjuvant therapy and radiotherapy with or without chemotherapy have traditionally represented the possible treatment options for oropharyngeal cancer. The adverse effects of non-surgical treatments and recent technical innovations have prompted a new interest in the surgical approach. However, in parallel to the possibility of achieving radical cancer clearance, we should remember the impact that traditional open surgery has on the patient's cosmesis, functionality and quality of life. As a result, transoral surgery is an attractive option for oropharyngeal tumors. The term "transoral surgery" only indicates that the tumor is accessed and resected via the oral cavity, but the surgeon can choose among different resection methods, such as transoral laser microsurgery, transoral robotic surgery, transoral videolaryngoscopic surgery, endoscopic laryngo-pharyngeal surgery, and transoral ultrasound surgery. The aim of this paper is to review the recent literature on the transoral treatment of oropharyngeal cancer, to standardize the terminology of transoral procedures, analyzing the common aspects, main differences and future perspectives of the various forms of transoral surgery.

Robotic surgical systems in maxillofacial surgery: a review

Throughout the twenty-first century, robotic surgery has been used in multiple oral surgical procedures for the treatment of head and neck tumors and non-malignant diseases. With the assistance of robotic surgical systems, maxillofacial surgery is performed with less blood loss, fewer complications, shorter hospitalization and better cosmetic results than standard open surgery. However, the application of robotic surgery techniques to the treatment of head and neck diseases remains in an experimental stage, and the long-lasting effects on surgical morbidity, oncologic control and quality of life are yet to be established. More well-designed studies are needed before this approach can be recommended as a standard treatment paradigm. Nonetheless, robotic surgical systems will inevitably be extended to maxillofacial surgery. This article reviews the current clinical applications of robotic surgery in the head and neck region and highlights the benefits and limitations of current robotic surgical systems.

Transoral Laser Microsurgery in Early Glottic Lesions

PURPOSE OF REVIEW

To give an overview of the evolvement of transoral laser microsurgery (TLM) in the treatment of early glottic carcinoma and highlight the contribution of recent literature.

RECENT FINDINGS

The indications and limits of TLM have been well specified. Effects on swallowing have been well documented. Introduction of narrow-band imaging (NBI) and diffusion-weighted magnetic resonance has been shown of additional value for outcome. The first reports on transoral robotic surgery show that it may be of added value in the future.

SUMMARY

TLM for early glottic carcinoma (Tis-T2) has very good oncological outcomes with indications of higher larynx preservation in TLM than that in radiotherapy. The anterior commissure is a risk factor if involved in the cranio-caudal plane, and reduced vocal fold mobility is a risk factor when this is due to arytenoid involvement. The best voice results are achieved when the anterior commissure can be left intact along with part of the vocal fold muscle although even in larger resections, patient self-reported voice handicap is still limited.

Comparison of fiber delivered CO2 laser and electrocautery in transoral robot assisted tongue base surgery

To compare intra-operative and post-operative effectiveness of fiber delivered CO₂ laser to monopolar electrocautery in robot assisted tongue base surgery. Prospective non-randomized clinical study. Twenty moderate to severe obstructive sleep apnea (OSA) patients, non-compliant with Continuous Positive Airway Pressure (CPAP), underwent Transoral Robotic Surgery (TORS) using the Da Vinci surgical robot in our University Hospital. OSA was treated with monopolar electrocautery in 10 patients, and with flexible CO₂ laser fiber in another 10 patients. The following parameters in the two sets are analyzed: Intraoperative bleeding that required cauterization, robot operating time, need for tracheotomy, postoperative self-limiting bleeding, length of hospitalization, duration until start of oral intake, pre-operative and post-operative minimum arterial oxygen saturation, pre-operative and post-operative Epworth Sleepiness Scale score, postoperative airway complication and postoperative pain. Mean follow-up was 12 months. None of the patients required tracheotomy and there were no intraoperative complications related to the use of the robot or the CO₂ laser. The use of CO₂ laser in TORS-assisted tongue base surgery resulted in less intraoperative bleeding that required cauterization, shorter robot operating time, shorter length of hospitalization, shorter duration until start of oral intake and less postoperative pain, when compared to electrocautery. Postoperative apnea-hypopnea index scores showed better efficacy of CO₂ laser than electrocautery. Comparison of postoperative airway complication rates and Epworth sleepiness scale scores were found to be statistically insignificant between the two groups. The use of CO₂ laser in robot assisted tongue base surgery has various intraoperative and post-operative advantages when compared to monopolar electrocautery.

Evidence and evidence gaps of laryngeal cancer surgery

Surgical treatment of laryngeal cancer has been established for decades. In addition to total laryngectomy, which was first performed in 1873, a large number or organ preservation surgical techniques, like open partial laryngectomy, transoral laser microsurgery, and transoral robotic surgery have been developed. Studies on laryngeal cancer surgery are mainly retrospective case series and cohort studies. The evolution of chemoradiation protocols and their analysis in prospective randomized trials have led to an increasing acceptance of non-surgical treatment procedures. In addition to an improvement of prognosis, in recent years the preservation of function and maintenance of life quality after primary therapy of laryngeal cancer has increasingly become the focus of therapy planning. Significant late toxicity after chemoradiation has been identified as an important issue. This leads to a reassessment of surgical concepts and initiation of studies on laryngeal cancer surgery which was additionally stimulated by the advent of transoral robotic surgery in the US. Improving the evidence base of laryngeal cancer surgery by successful establishment of surgical trials should be the future goal.

Flex Robotic System in transoral robotic surgery: The first 40 patients

BACKGROUND

The Flex Robotic System is a new robotic device specifically developed for transoral robotic surgery (TORS).

METHODS

We performed a prospective clinical study, assessing the safety and efficacy of the Medrobotics Flex Robotic System. A total of 40 patients required a surgical procedure for benign lesions (n = 30) or T1 and T2 carcinomas (n = 10). Access and visualization of different anatomic subsites were individually graded by the surgeon. Setup times, access and visualization times, surgical results, as well as adverse events were documented intraoperatively.

RESULTS

The lesions could be exposed and visualized properly in 38 patients (95%) who went on to have a surgical procedure performed with the Flex Robotic System, which were intraoperatively evaluated as successful. No serious adverse events occurred.

CONCLUSION

Lesions in the oropharynx, hypopharynx, or supraglottic larynx could be successfully resected using the Flex Robotic System, thus making the system a safe and effective tool in transoral robotic surgery. © 2016 Wiley Periodicals, Inc. Head Neck 39: 471-475, 2017.

A european multicenter study evaluating the flex robotic system in transoral robotic surgery

OBJECTIVES/HYPOTHESIS

To evaluate the application of the Flex Robotic System in transoral robotic surgery (TORS).

STUDY DESIGN

Multicenter, prospective, open-label, single-armed clinical study.

METHODS

A prospective clinical follow-up multicenter study was performed from July 2014 to October 2015 assessing the safety and efficacy of the Medrobotics Flex Robotic System for access and visualization of the oropharynx, hypopharynx, and larynx as well as for resection of benign and malignant lesions. A total of 80 patients were enrolled. Access and visualization of five anatomic subsites (base of tongue, palatine tonsil area, epiglottis, posterior pharyngeal wall, and false vocal cords) were individually graded by the surgeon. Setup times, access and visualization times, surgical results, and adverse events were documented.

RESULTS

The relevant anatomic structures could be exposed and visualized properly in 75 patients, who went on to have a surgical procedure performed with the Flex Robotic System. Access and visualization of the palatine tonsil area, posterior pharyngeal wall, epiglottis, and posterior pharyngeal wall were excellent. However, false vocal cords and vocal cords were more difficult to expose. Seventy-two patients were treated successfully with the Flex Robotic System. There were no serious or unanticipated device-related adverse events caused by the Flex Robotic System.

CONCLUSIONS

Lesions in the oropharynx, hypopharynx, and larynx could be successfully resected with the Flex Robotic System, specifically developed for TORS. Our study provides evidence that the Flex Robotic System is a safe and effective tool in TORS. Laryngoscope, 2016 127:391-395, 2017.

Transoral robotic surgery (TORS) for laryngeal and hypopharyngeal cancers

Transoral robotic surgery (TORS) is increasingly used in laryngeal/hypopharyngeal cancer surgery. Ablative procedures described in these anatomical sites include: (i) supraglottic laryngectomy, (ii) total laryngectomy, (iii) glottic cordectomy, and (iv) partial pharyngectomy. TORS supraglottic laryngectomy remains the most commonly performed of these procedures. Initial oncologic and functional outcomes with these procedures are promising and comparable to other treatment options. As robotic instrumentation technology advances a rise in TORS laryngeal/hypopharyngeal surgery is anticipated.

Transoral robotic surgery in the management of head and neck tumours

The article reviews the use of robotic technology for head and neck tumours. The authors discuss the development of transoral robotic surgery (TORS), the current status of the technology, and the set-up in the operating room. The article provides a review of the literature, highlighting the applications, advantages, functional outcomes, and disadvantages of TORS for each anatomic subsite (oropharynx, hypopharynx, larynx, parapharyngeal space, and skull base). New challenges related to reconstruction are also presented. Overall early functional and oncologic outcome data are promising; further long-term prospective trials are still needed to confirm the oncological safety of TORS.

Current trends in robotic surgery for otolaryngology

As minimally invasive surgery has become common in head and neck surgery, the role of robotic surgery has expanded from thyroid surgery and transoral robotic surgery (TORS) of the oropharynx and supraglottic to other areas. Surgeons have advanced the limits of TORS, adapting lasers to the Da Vinci robot for glottic cancer, and combining existing techniques for transoral supraglottic laryngectomy and hypopharyngectomy to perform transoral total laryngectomy. Skull base approaches have been reported with some success in case reports and cadaver models, but the current instrument size and configuration limit the applicability of the current robotic system. Surgeons have reported reconstruction of the head and neck via local and free flaps. Using the previously reported approaches for thyroidectomy via modified facelift incision, neck dissection has also been reported. Future applications of robotic surgery in otolaryngology may be additionally expanded, as several new robotic technologies are under development for endolaryngeal work and neurotology.