Transoral robotic surgery for the management of obstructive sleep apnea: a systematic review and meta-analysis

Surgical failure guided by DISE in patients with obstructive sleep apnea: a systematic review and meta-analysis

OBJECTIVES

The failure rate and risk factors of upper airway surgery with drug induced sleep endoscopy (DISE) remain unknown in the treatment of obstructive sleep apnea (OSA). This review aims to analyze the failure rate of upper airway surgery with DISE and identify obstruction sites for surgical failure.

METHODS

A systematic review was conducted using PubMed, Embase, Web of Science, and Google Scholar until May 20th, 2023. We included studies that used DISE to assess obstructive sites before upper airway surgery and reported surgical failure rates and outcomes in patients with OSA.

RESULTS

25 studies with a total of 1522 patients were included in the systematic review and meta-analysis. Upper airway surgery guided by DISE had a relatively low failure rate of 37% (95% CI 0.31-0.44) in the random effects model (I2 = 85.97%, P < 0.001). According to the velum, oropharynx, tongue base, and epiglottis (VOTE) scoring system, major risk factors for surgical failure included circumferential collapse at the velum, lateral wall collapse and small tonsils at the oropharynx, anterior-posterior lingual collapse and complete collapse at the tongue base. High body mass index and large preoperative apnea hypopnea index were also risk factors for OSA surgical failure.

CONCLUSIONS

Upper airway surgery guided by DISE in patients with OSA had a low failure rate of 37%. DISE can identify obstruction sites associated with surgical failure and guide single-level and multi-level surgeries.

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

Homocysteine Levels in Severe OSA Patients Before and After TORS-OSA Surgery

OBJECTIVE

The increased risk of cardiovascular diseases owing to a high level of serum homocysteine has been widely reported. Literature has demonstrated that patients with obstructive sleep apnea/hypopnea syndrome (OSA) had a higher homocysteine level than control group. This study aimed to investigate the alteration of serum homocysteine levels in severe OSA patients receiving transoral robotic surgery (TORS).

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary academic medical center.

METHODS

Data of polysomnography (PSG) and serum homocysteine levels before and at least 3 months after the surgery were collected and analyzed via paired t tests. A subgroup analysis based on the preoperative homocysteine level (≥15 mcmol/L, as hyperhomocysteinemia group) was conducted to compare the intergroup differences of homocysteine decrease. Pearson's correlation was used to survey the relationships between the changes of major PSG parameters and the levels of homocysteine decrease at baseline and after TORS-OSA surgery.

RESULTS

Two hundred sixty-one patients with severe OSA were enrolled. There were significant improvements in major PSG parameters after TORS-OSA surgery. Homocysteine levels significantly decreased from 12.1 ± 3.9 to 11.4 ± 3.7 mcmol/L (difference = -0.7 ± 2.8 mcmol/L, p = .001) postoperatively, which was shown in the hyperhomocysteinemia group (difference = -2.9 ± 4.7 mcmol/L, p = .007) to a greater extent. Pearson's correlation revealed that ΔODI (oxygen desaturation index/h) was the predominant estimate with a positive association with Δhomocysteine (r = 0.525, p = .012).

CONCLUSION

TORS-OSA surgery could decrease homocysteine levels in OSA patients. The effects were more relevant in severe OSA patients with abnormal preoperative homocysteine levels.

Practising transoral robotic surgery in a middle-income country: surgical outcomes and early challenges

Transoral robotic surgery is a minimally invasive surgical technique that recently debuted in Malaysia. However, there are concerns over its cost, practicality, and feasibility in local settings. Our study aims to evaluate the surgical outcomes of transoral robotic surgery and discuss its learning curves. The clinical records of all patients who underwent transoral robotic surgery in a university hospital were reviewed. 25 patients were identified with a mean age of 43.9 years. The commonest indication was obstructive sleep apnoea (OSA) (76%), followed by base of tongue carcinoma (16%), recurrent tonsilitis and Wharton's duct cyst (4% each). For excision of tongue base in obstructive sleep apnoea without epiglottectomy, the mean operating time was 2.3(±0.9) hours with an average of 2.8(±0.4) days of hospital stay. The success rate for OSA surgery was seen in 78.9% of cases. The mean operating time for transoral excision of tongue base carcinoma was 4.3(±2.5) hours, whereas the mean hospital stay was 9(±3.6) days. All surgical margins were cleared with no recurrence except for one patient. The recurrent tumour was successfully excised via transoral robotic surgery, and he remained disease free after one year. The most frequent post-operative complaints were dysphagia, post-nasal drip, and hypogeusia. Transoral robotic surgery in Malaysia is in the commencement phase, where some pitfalls are expected. Opportunities should be given for more surgeons to acquire this technique so that minimally invasive surgery for head and neck diseases is readily available for patients in middle-income countries.

Quality of Life and Excessive Daytime Sleepiness in Adults with Obstructive Sleep Apnea Who Are Treated with Multilevel Surgery or Adherent to Continuous Positive Airway Pressure

Obstructive Sleep Apnea (OSA) syndrome is a respiratory sleep disorder characterized by a reduction (hypopnea) in or a complete cessation (apnea) of airflow in the upper airways at night, in the presence of breathing effort. The gold standard treatment for OSA is ventilation through continuous positive airway pressure (CPAP), although this often shows poor patient compliance. In recent years, transoral robotic surgery (TORS) has been proposed as a valid surgical treatment for patients suffering from OSA in a multilevel surgical setting. The aim of this study is to analyze the effects on QoL and daytime sleepiness of multilevel surgery for OSA (barbed pharyngoplasty + transoral robotic surgery). Furthermore, we compared the impact on QoL and daytime sleepiness of two different treatments for patients with moderate to severe OSA, such as CPAP and TORS. Sixty-seven OSA patients who underwent multilevel robotic surgery and sixty-seven OSA patients treated with CPAP were enrolled, defined as Group 1 and Group 2, respectively. The Glasgow Benefit Inventory (GBI) questionnaire was administrated to evaluate the changes in the QoL. Respiratory outcomes were evaluated and compared. Group 1 showed a GBI total average value of +30.4, whereas Group 2, a value of +33.2 (p = 0.4). General benefit score showed no difference between groups (p = 0.1). Better values of social status benefit (p = 0.0006) emerged in the CPAP Group, whereas greater physical status benefit (p = 0.04) was shown in the TORS Group. Delta-AHI (-23.7 ± 14.3 vs. -31.7 ± 15.6; p = 0.001) and Delta-ODI (-24.5 ± 9.5 vs. -29.4 ± 10.5; p = 0.001) showed better values in the CPAP group. Therapeutic success rate of the Multilevel TORS Group was 73.1% and 91% in the CPAP group (p = 0.01), respectively. Multilevel TORS and CPAP have a positive effect on the quality of life of OSA patients. Greater social support has been reported in the CPAP group and better physical health status in the TORS group. No statistical difference emerged in the reduction in daytime sleepiness between both groups.

TORS as Part of Multilevel Surgery in OSA: The Importance of Careful Patient Selection and Outcomes

Transoral robotic surgery (TORS) for Obstructive Sleep Apnea (OSA) is a relatively young technique principally devised for managing apneas in the tongue base area. This study summarizes and presents our personal experience with TORS for OSA treatment, with the aim to provide information regarding its safety, efficacy, and postoperative complications. A retrospective study was conducted on patients undergoing TORS with lingual tonsillectomy through the Da Vinci robot. The effectiveness of the surgical procedure was assessed employing the Epworth Sleepiness Scale (ESS) and overnight polysomnography with the Apnea-Hypopnea Index (AHI). A total of 57 patients were included. Eighteen patients (31.6%) had undergone previous surgery. The mean time of TORS procedure was 30 min. Base of tongue (BOT) management was associated with other procedures in all patients: pharyngoplasty (94%), tonsillectomy (66%), and septoplasty (58%). At 6 months follow-up visit, there was a significant improvement in AHI values (from 38.62 ± 20.36 to 24.33 ± 19.68) and ESS values (from 14.25 ± 3.97 to 8.25 ± 3.3). The surgical success rate was achieved in 35.5% of patients. The most frequent major complication was bleeding, with the need for operative intervention in three cases (5.3%). The most common minor complications were mild dehydration and pain. TORS for OSA treatment appears to be an effective and safe procedure for adequately selected patients looking for an alternative therapy to CPAP.

Effects of TORS-OSA Surgery on Lower Urinary Tract Symptoms, Overactive Bladder Symptoms, and Nocturia in Male Patients with Obstructive Sleep Apnea/Hypopnea Syndrome

OBJECTIVE

To determine the presence of lower urinary tract symptoms (LUTS), and overactive bladder (OAB) symptoms in men with obstructive sleep apnea/hypopnea syndrome (OSA) and the effects of transoral robotic surgery (TORS) for the treatment of OSA on these conditions.

MATERIALS AND METHODS

One hundred twenty-three patients with a diagnosis of OSA were prospectively enrolled. The evaluations of LUTS and OAB symptoms were based on self-administered questionnaires containing international prostate symptom score (IPSS) and OAB symptom score (OABSS), respectively. Men with an OABSS urgency score of ≥2 and sum score of ≥3 were considered to have OAB. The therapeutic outcomes were assessed at baseline, and 12 weeks after TORS-OSA Surgery.

RESULTS

There were significant differences in IPSS, and OABSS according to OSA severity. After TORS-OSA surgery, significant improvements on OSA severity, daytime quality of life (QoL) and nighttime sleep quality were observed. TORS-OSA surgery was also associated with a statistically significant improvement of LUTS, LUTS QoL score, and OAB symptoms (IPSS 22.1% decrease; IPSS QoL score 21.1% decrease; OABSS17.4% decrease) at post-operative 3 months' follow-up. The presence of OAB, and severe nocturia was significantly reduced from 22.8% to 11.4% (p=0.001), 5.7% to 0.8% (p=0.031) after TORS-OSA surgery. There were no patients who had acute airway compromise or massive bleeding peri- or post-operatively.

CONCLUSION

TORS upper airway surgery could improve LUTS and OAB symptoms on male patients with OSA in addition to improvement of major parameters of sleep study and sleep-related QoL.

Swallowing biomechanics pre-multi-level and post-multi-level upper airway surgery for obstructive sleep apnea

STUDY OBJECTIVES

The effect of contemporary multi-level upper airway surgery for obstructive sleep apnea (OSA) on swallowing is unclear. This study assessed the biomechanical swallowing function in participants with OSA pre- and post-modified uvulopalatopharyngoplasty and coblation channeling of the tongue (mUPPP+CCT).

METHODS

In this prospective, longitudinal study adults diagnosed with moderate-severe OSA who underwent mUPPP+CCT surgery had swallowing biomechanics assessed using high-resolution pharyngeal manometry (HRPM) and analyzed with swallowgateway.com. Symptomatic swallowing difficulty was evaluated using the Sydney Swallow Questionnaire (SSQ ≥234). General linear mixed model analysis was conducted to evaluate the difference pre- and post-mUPPP+CCT. Data presented as mean [95% confidence intervals].

RESULTS

HRPM assessments were conducted in 10 participants (7 male; median age 50 [IQR 36-65]) pre- and repeated post-operatively at 9 months [IQR 6-13]. Self-reported dysphagia was unchanged following surgery (SSQ 149 [53, 447] to 168 [54, 247]; P =0.093). HRPM outcomes indicated reduced mesopharyngeal pressures (148 [135, 161] to 124 [112, 137] mm Hg.s.cm; P =0.011), reduced hypopharyngeal pressures (113 [101, 125] to 93 [84, 102] mm Hg.s.cm; P =0.011) and reduced upper esophageal sphincter relaxation pressure (5 [4, 6] to 2 [1,3] mm Hg; P =0.001) but no change to velopharyngeal pressures (135 [123, 147] to 137 [117, 157] mm Hg.s.cm; P =0.850) post-surgery.

CONCLUSIONS

mUPPP may have less implications on the swallow mechanism than previously suspected. In contrast, the reduction in mesopharyngeal contractile pressures associated with CCT, although within normal limits, may effect bolus propulsion. Biomechanical alterations were insufficient to worsen self-reported swallowing function.

Evaluation of a 3D-Printed Transoral Robotic Surgery Simulator Utilizing Artificial Tissue

OBJECTIVES/HYPOTHESIS

Transoral robotic surgery (TORS) poses challenges for operators in training, with limited robot access on a platform requiring distinct surgical skills. Few simulators exist, and current virtual reality training modules exclude head and neck simulations. This study evaluates the construct validity for a novel low-cost TORS simulator.

STUDY DESIGN

Single institution prospective observational study.

METHODS

Using 3D-printed oral cavity structures and replaceable artificial tissue components, a modular TORS simulator was constructed for short-duration hands-on simulations with the da Vinci SI robot. Sixteen surgeons of differing robotic skill levels, no experience (novice), prior experience, and formal robot training, participated in simulated tonsil and tongue base tumor resections. Video recordings of each participant were graded by a blinded robotically trained surgeon using a 35-point Global Evaluative Assessment of Robotic Surgery (GEARS) criterion adapted for the TORS simulator.

RESULTS

Operators reporting formal robotic training or prior robot experience achieved significantly higher mean total GEARS scores compared to novice operators (32 vs. 20.5; P < .001). Overall, mean total GEARS scores correlated with reported experience level; novice operators scored 54% of total points at 19 (4.5), operators with prior experience scored 82.3% of total points at 28.8 (2.6), and robotically trained operators scored 97.1% of total points at 34 (1.7).

CONCLUSION

With a GEARS criterion, our simulator successfully differentiated novice from experienced and robotically trained operators of the da Vinci SI robot during simulated tonsillectomy and base of tongue resections. These findings support the construct validity of this prototype simulator and offer a foundation for further testing of predictive validity.

LEVEL OF EVIDENCE

2 Laryngoscope, 2021.

Quantification of the Impact of Intraoperative Ultrasound in Transoral Robotic Tongue Base Reduction

OBJECTIVES/HYPOTHESIS

Transoral robotic surgery (TORS) in the base of the tongue (BOT) reduction has been shown to decrease the apnea-hypopnea index (AHI) and improve daytime sleepiness in obstructive sleep apnea (OSA) patients. Intraoperative ultrasound (IOU) can be employed to guide the surgery and prevent massive bleeding.

STUDY DESIGN

Cohort study with historical control.

METHODS

A cohort study to compare the outcomes between OSA patients who received TORS with and without IOU assistance.

RESULTS

From 2016 to 2019, this study enrolled 80 OSA patients who underwent TORS in BOT: 57 in the IOU(+) and 23 in IOU(-) groups. The TORS with IOU presented with shorter operative time, less blood loss, and greater excised BOT volume. The IOU(+) group had greater improvement in the AHI and subjective questionnaire evaluation. The excised volume of BOT was significantly associated with the change in AHI.

CONCLUSION

The IOU could improve outcomes in BOT reduction surgery without raising the risk of surgical complications.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Combined Transoral Robotic Tongue Base Surgery and Palate Surgery in Obstructive Sleep Apnea Syndrome: Modified Uvulopalatopharyngoplasty versus Barbed Reposition Pharyngoplasty

Background: Successful surgery outcomes are limited to moderate to severe obstructive sleep apnea (OSA) syndrome. Multilevel collapse at retropalatal and retroglossal areas is often found during the drug-induced sleep endoscopy (DISE). Therefore, multilevel surgery is considered for these patients. The aim of our study was to survey surgical outcomes by modified uvulopalatoplasty (UPPP) plus transoral robotic surgery tongue base reduction (TORSTBR) versus barbed repositioning pharyngoplasty (BRP) plus TORSTBR. Methods: The retrospective cohort study was performed at a tertiary referral center. We collected moderate to severe OSA patients who were not tolerant to positive pressure assistant PAP from September 2016 to September 2019; pre-operative–operative Muller tests all showed retropalatal and retroglossal collapse; pre-operative Friedman Tongue Position (FTP) > III, with the tonsils grade at grade II minimum, with simultaneous velum (V > 1) and tongue base (T > 1), collapsed by drug-induced sleep endoscopy (DISE) under the VOTE grading system. The UPPP plus TORSTBR (n = 31) and BRP plus TORSTBR (n = 31) techniques were offered. We compare the outcomes using an Epworth sleepiness scale (ESS) questionnaire, and measure the patients’ apnea–hypopnea index (AHI), lowest O₂ saturation, cumulative time spent below 90% (CT90), and arousal index (AI) by polysomnography six months after surgery; we also measure their length of hospital stay and complications between these two groups. Results: Comparing BRP plus TORSTBR with UPPP plus TORSTBR, the surgical success rate is 67.74% and 38.71%, respectively. The significantly higher surgical success rate in the BRP plus TORSTBR group was noted. The surgical time is shorter in the BRP plus TORSTBR group. The complication rate is not significant in pain, bleeding, dysgeusia, dysphagia, globus sensation, and prolonged suture stay, even though the BRP plus TORSTBR rendered a higher percentage of globus sensation during swallowing and a more prevalent requirement of suture removal one month after surgery. The length of hospital stay is not significantly different between the two groups. Conclusion: In conclusion, BRP plus TORSTBR is a considerable therapy for moderate to severe OSA patients with DISE showing a multi-level collapse in velum and tongue base area. The BRP technique might offer a better anterior–posterior suspension vector for palate level obstruction.

OSA Upper Airways Surgery: A Targeted Approach

Obstructive sleep apnea syndrome (OSA) is a multi-factorial disorder, with quite complex endotypes, consisting of anatomical and non-anatomical pathophysiological factors. Continuous positive airway pressure (CPAP) is recognized as the first-line standard treatment for OSA, whereas upper airway (UA) surgery is often recommended for treating OSA patients who have refused or cannot tolerate CPAP. The main results achievable by the surgery are UA expansion, and/or stabilization, and/or removal of the obstructive tissue to different UA levels. The site and pattern of UA collapse identification is of upmost importance in selecting the customized surgical procedure to perform, as well as the identification of the relation between anatomical and non-anatomical factors in each patient. Medical history, sleep studies, clinical examination, UA endoscopy in awake and drug-induced sedation, and imaging help the otorhinolaryngologist in selecting the surgical candidate, identifying OSA patients with mild UA collapsibility or tissue UA obstruction, which allow achievement of the best surgical outcomes. Literature data reported that the latest palatal surgical procedures, such as expansion sphincter palatoplasty or barbed reposition palatoplasty, which achieve soft palatal and lateral pharyngeal wall remodeling and stiffening, improved the Apnea Hypopnea Index, but the outcome analyses are still limited by methodological bias and the limited number of patients' in each study. Otherwise, the latest literature data have also demonstrated the role of UA surgery in the improvement of non-anatomical factors, confirming that a multidisciplinary and multimodality diagnostic and therapeutical approach to OSA patients could allow the best selection of customized treatment options and outcomes.

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.

Change in Quality of Life of OSAHS Patients with Minimally Invasive Surgery or CPAP Therapy: A 2-year Retrospective, Single-center Parallel-group Study

BACKGROUND

By including untreated obstructive sleep apnea-hypopnea syndrome (OSAHS) patients as the control group, this study explores the influence of minimally invasive surgical treatment and continuous positive airway pressure (CPAP) therapy on OSAHS patients, with the subjective and objective performance. The study also discusses their relationship, determines the effect factor, and provides a simple and practical method for evaluation of clinical efficacy.

METHODS

A total of 90 OSAHS patients, who were diagnosed in the Sleep Disorders Diagnosis and Treatment Center of Sichuan Province from May 2014 to May 2016, were selected for the present study. These patients were divided into three groups: surgery group, CPAP group, and untreated group. These patients were followed up at six months, one year, and two years, respectively. The physiological indicators, clinical symptoms, degree of daytime sleepiness and quality of life were compared among these three groups. The daytime sleepiness and the quality of life before and after minimally invasive surgery and CPAP treatment were evaluated, and the subjective and objective efficacy of surgery and CPAP treatment was explored.

RESULTS

Among these 90 patients, 11 (12.2%) patients had hypertension, while two (2.2%) patients had diabetes. The average AHI score was 50.53±23.39 per hour, and the mean minimum oxygen saturation and mean oxygen saturation was 71.25±14.16% and 90.13±5.90%, respectively. There were statistically significant differences in mouth breathing, morning sore throat and daytime sleepiness in the group having received surgery at 0.5 year and one year. In the CPAP group, there were statistically significant differences in mouth breathing, morning sore throat and daytime sleepiness at 0.5 year, one year and two years. Moreover, there were statistically significant differences in memory loss at one year and two years, and there were statistically significant differences in frequent nocturia at one year. The ESS value in the surgery group decreased at 0.5 year and one year, but increased at two years. The situation was the same in terms of the total points and in each dimension of the SF-36 paramter. The delta values of ESS among the three groups had statistical significance at 0.5 year, one year and two years, in which the CPAP group experienced the most changes, followed by the surgery group and the group received health education.

CONCLUSION

For minimally invasive surgery, CPAP therapy and health education can improve daytime sleepiness and quality of life. CPAP therapy was found to be the most effective, followed by minimally invasive surgery and provision of health education. However, the treatment of OSAHS should be comprehensive.

Surgical, clinical, and functional outcomes of transoral robotic surgery used in sleep surgery for obstructive sleep apnea syndrome: A systematic review and meta-analysis

We investigated safety and efficacy of transoral robotic surgery (TORS) for base of tongue (BOT) reduction in obstructive sleep apnea syndrome (OSAS) patients. PubMed, Cochrane Library, and Scopus were searched. A meta-analysis was performed. Random effects models were used. Thirty-one cohorts met our criteria (1693 patients). The analysis was based mostly on retrospective studies. The summary estimate of the reduction of Apnea-Hypoxia Index (AHI) was 24.25 abnormal events per hour (95% CI: 21.69-26.81) and reduction of Epworth Sleepiness Scale (ESS) was 7.92 (95% CI: 6.50-9.34). The summary estimate of increase in lowest O₂ saturation was 6.04% (95% CI: 3.05-9.03). The success rate of TORS BOT reduction, either alone or combined with other procedures, was 69% (95% CI: 64-79). The majority of studies reported low level of evidence but suggested that TORS BOT reduction may be a safe procedure associated with improvement of AHI, ESS, and lowest O₂ saturation.

A new landmark for lingual artery identification during transoral surgery: Anatomic-radiologic study

BACKGROUND

A landmark for the identification of the lingual artery (LA) through a transoral perspective can provide surgeons with an easy method to prevent and manage intraoperative bleeding during transoral approach to the base of tongue (BOT).

METHODS

Thirteen tongue and five head and neck specimens were dissected to identify and assess the reliability of the lingual point (LP) as a new landmark for the LA at BOT. The pathway of 42 LAs was radiologically evaluated; axial depth and vertical offset were measured for each LA.

RESULTS

Dissection study: a description of LP is provided; the LA was easily identified in all specimens (36/36 sides) using LP as a landmark. Radiologic study: the mean depth of the LA was 4.2 mm, the mean vertical offset was 1.3 mm.

CONCLUSIONS

LP is a simple and reliable landmark for identification of the LA, potentially helping surgeons to prevent and manage intraoperative bleeding.

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.

Real-Time, Intraoperative, Ultrasound-Assisted Transoral Robotic Surgery for Obstructive Sleep Apnea

OBJECTIVES/HYPOTHESIS

To investigate the lingual artery (LA) position in the tongue base through intraoperative ultrasound (IOU) imaging during transoral robotic surgery (TORS) and evaluate bleeding complications with or without the assistance of IOU.

STUDY DESIGN

Cohort study with historical control.

METHODS

Patients with obstructive sleep apnea (OSA) who underwent TORS for tongue base resection were recruited since 2016. During surgery, ultrasound imaging was employed to identify anatomic parameters of the LA in the tongue base, including distance to the midline and arterial depth and diameter.

RESULTS

Ninety-three OSA patients (82 men, 88.2%) were analyzed. Mean age was 42.2 ± 10.0 years and body mass index was 29.2 ± 4.5 kg/m² . Average apnea-hypopnea index (AHI) was 58.1 ± 21.4 events/hour. Overall, 70 patients who underwent TORS with IOU had a shorter operation time (191.7 ± 3.8 vs. 220.1 ± 6.6 minutes), lower total blood loss (11.3 ± 10.8 vs. 19.6 ± 26.7 mL), and higher tongue base reduction volume (7.1 ± 2.5 vs. 3.9 ± 1.6 mL) than 23 patients who underwent TORS without IOU. Significant predictors of arterial depth included higher AHI level during the rapid eye movement sleep (P = .038), larger tonsil size (P = .034), and more elevated Friedman tongue position (P = .012). Postoperative complications associated with LA injury were not found in patients subjected to IOU.

CONCLUSIONS

With the assistance of IOU, surgeons can confidently determine LA position. The use of IOU can maximize efficiency and minimize catastrophic bleeding complications when OSA patients undergo TORS for tongue base resection.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E1383-E1390, 2021.

Transoral robotic OSA surgery

Continuous positive airway pressure (CPAP) is the primary treatment of obstructive sleep apnea/hypopnea syndrome (OSA). Most sleep physicians are in agreement that a certain number of OSA patients cannot or will not use CPAP. Although other conservative therapies such as oral appliance, sleep hygiene and sleep positioning may help some of these patients, there are many who fail all conservative treatments. As experts of upper airway diseases, we often view an airway clearly and help OSA patients understand the importance of assessment and treatment for OSA. Surgery for OSA is not a substitute for CPAP but is an alternative treatment for those who failed conservative therapies and therefore have no other options. Transoral robotic surgery (TORS) is a relatively new technique and a valid option with minor post-operative morbidities for selected OSA patients. In the article, we provide an updated overview of the role and evidence of TORS for the treatment of OSA.

Transoral Endoscopic Coblation Tongue Base Surgery in Obstructive Sleep Apnea: Resection versus Ablation

BACKGROUND

A new transoral tongue base surgical procedure for the treatment of snoring and obstructive sleep apnea (OSA) is described. It is named "Robo-Cob" technique because it is similar to transoral robotic surgery (TORS) but it is performed by means of coblation technology in order to resect the tongue base in countries where TORS is not an available option for such benign conditions.

METHODS

In this prospective, randomized, controlled trial, the new Robo-Cob technique was carried out in 25 adult OSA patients with confirmed tongue base hypertrophy at preoperative drug-induced sedation endoscopy. The results of this procedure were compared with the coblation endoscopic lingual lightening (CELL) technique used to ablate (or minimally resect) the central part of the tongue base, in another 25 adult OSA patients with similar characteristics (age, sex, preoperative body mass index and Apnea-Hypopnea Index, AHI). The base of tongue surgery was part of multilevel surgery including also septoturbinoplasty and barbed reposition pharyngoplasty (with/without tonsillectomy).

RESULTS

In this study, the Robo-Cob technique is proved to be feasible and effective in all cases either alone or when combined with other procedures in multilevel surgical settings. No/minimal intraoperative or postoperative complications were observed. Postoperative pain as measured by visual analog scale ranged from 3 to 7. No tracheostomy was done in any patient. Objective clinical improvement was confirmed by a level 3 polygraphy performed 6 months after surgery. There was significant difference in operative time at the level of the tongue base between Robo-Cob and CELL techniques, with shorter times observed within the Robo-Cob group. Moreover, the Robo-Cob technique provided tongue base tissue specimens that allowed measurement of the volume that ranged from 5 to 17 cm3 (mean 11.64 ± 3.49 cm3). It was found that resection of at least 10 cm3 of tongue base tissue was associated with better outcomes in terms of postoperative AHI reduction.

CONCLUSION

In this study, the added values of using coblation for resection and not ablation appear to be the short surgical time, the low postoperative tissue edema, and the possibility of providing tissue specimens to measure resected volumes.

Alternative Applications of Trans-Oral Robotic Surgery (TORS): A Systematic Review

Background: The role of robotic surgery in the field of oncology has been widely described, in particular for the tumours of the oropharynx and larynx, but its efficacy for benign pathology is inconsistent. Methods: An exhaustive review of the English literature on trans-oral robotic surgery (TORS) for benign conditions was performed using PubMed electronic database. Results: The research was performed in March 2019 and yielded more than eight hundred articles, with 103 meeting the inclusion criteria and considered in the present study. Conclusions: The application of TORS for the treatment of obstructive sleep apnoea syndrome seems to be particularly well documented. Additionally, there exists a special interest in its use where high precision in limited anatomic space is required. There are still different structural and economic limitations for the application of TORS, however, the progressive technologic innovations and the increasing adoption of robotic surgery seem to encourage the uptake of this technique.

Trans-oral robotic surgery versus coblation tongue base reduction for obstructive sleep apnea syndrome

Objectives

To compare the efficacy of trans-oral robotic surgery (TORS) with that of coblation assisted tongue base reduction surgery in patients with obstructive sleep apnea syndrome (OSAS).

Subjects and Methods

The medical charts were retrospectively reviewed for all OSAS patients admitted to one institution for surgical intervention between 2012 and 2017. We analyzed 33 cases; 16 patients received TORS and 17 received coblation surgery for tongue base reduction. Both groups received concomitant uvulopalatoplasty. Surgical outcomes were evaluated by comparing the initial polysomnography (PSG) parameters with the follow-up PSG data (at least 3 months after the surgery). Epworth sleepiness scale (ESS) and complications were also compared between the 2 groups.

Results

The success rate (≥50% reduction of pre-operative AHI and post-operative AHI <20) in the TORS group and coblation group were 50% and 58%, respectively, and there was no significant difference (p = .611). The AHI (mean ± SD) reduction in the TORS and coblation groups were 24.9 ± 26.5 events/h and 19.4 ± 24.8 events/h, respectively; the between-group difference was not significant (p = .631). ESS improvement did not differ significantly between the TORS and coblation groups (3.8 ± 6.6 and 3.1 ± 9.2, respectively, p = .873). The rates of minor complication were higher in the TORS group (50%) than that of the coblation group (35.3%) without statistical significance (p = .393).

Conclusion

TORS achieved comparable surgical outcomes compared to coblation assisted tongue base reduction surgery in OSAS patients. Multilevel surgery using either TORS or coblation tongue base reduction combined with uvulopalatoplasty is an effective approach for the management of OSAS.

The Impact of Upper Airway Stimulation on Swallowing Function

OBJECTIVE

To evaluate the impact of upper airway stimulation therapy (UAS) on swallowing function in patients with obstructive sleep apnea.

STUDY DESIGN

Prospective cohort study.

SETTING

Academic medical center.

PARTICIPANTS AND OUTCOME MEASURES

We recorded demographic, preoperative polysomnogram (PSG), operative, and postoperative PSG data. We assessed the patients swallowing function using the Eating Assessment Tool (EAT-10) dysphagia questionnaire. This was administered both pre- and postoperatively. The postoperative EAT-10 survey was administered at least 3 months after UAS implantation.

RESULTS

During the study period, 27 patients underwent UAS implantation, completed the pre- and postoperative EAT-10 questionnaire, met inclusion/exclusion criteria, and were included in the study. The cohort consisted of 16 men and 11 women with a mean age of 63.63 years. The mean preoperative BMI, Epworth Sleepiness Scale (ESS), and Apnea Hypopnea Index (AHI) were 29.37, 10.33, and 34.90, respectively. The mean postoperative ESS and AHI were 5.25 and 7.59, respectively. These were both significantly lower than the preoperative values (P = .026 and P < .001). The mean pre- and postoperative EAT-10 scores were 0.37 and 0.22, respectively (P = .461).

CONCLUSION

Our data suggest that UAS likely does not lead to postoperative dysphagia.

The emerging role of trans-oral robotic surgery for the detection of the primary tumour site in patients with head-neck unknown primary cancers: A meta-analysis

The identification of the site in head neck unknown primary (HNUP) tumour is of utmost importance to help select best treatment while decreasing treatment-related morbidity and mortality. The primary purpose of this study is to demonstrate that TORS may be a valuable tool in detecting primary tumour. Studies were systematically searched in the PubMed, EMBASE, the Cochrane Library and CENTRAL electronic databases. A total of 12 selected studies (349 patients) were analyzed. The primary tumour detection and positive surgical margins rates were 70.8% and 19.4%, respectively. The rate of HPV-related tumour was 71.3%. The primary tumour was mainly in base of tongue (64%). In conclusion, TORS seems to be an effective surgical approach both in terms of detection of primary tumour site and in terms of therapeutic perspective for HNUP. In particular, a subset of HPV-related tumours might benefits all advantages from this surgical modality.

Robot-assisted Tongue Base Resection ensures favorable therapeutic outcome to Obstructive Sleep Apnea patients with Lingual tonsil hypertrophy

Tongue base (TB) narrowing is recognized as a significant site of upper airway collapse during sleep in obstructive sleep apnea (OSA) patients and robot technology is expected to have promising clinical utility in OSA patients with TB narrowing. The purpose of our study is to demonstrate the better therapeutic conditions and favorable indications of robot-assisted TB resection (TBR) in OSA. We performed robot-assisted TBR combined with nasal and palatal surgery in 16 OSA patients with any of the following characteristics: severe TB narrowing (over grade II) and moderate or severe OSA. The preoperative median AHI was 48.8/hr and the median lowest SaO₂ was 82.0%. The median AHI decreased to 18.7/hr and ten patients (62.5%) were included in the responder group following robot-assisted TBR combined with nasal and palatal surgery. The lowest SaO₂ improved to 90.5% and the posterior airway space (PAS) was significantly increased following robot-assisted TBR. Cephalometric results showed that wider PAS were observed in responders compared to non-responders prior to robot-assisted TBR. Interestingly, there was greater improvement in the objective parameters including PAS in the OSA patients with lingual tonsilar hypertrophy than they were in those without and all patients with lingual tonsillar hypertrophy (n = 6) responded to robot-assisted TBR. Robot-assisted TBR exhibited minimal morbidity and postoperative complications in OSA patients. Robot-assisted TBR can be considered a promising and innovative surgical option to reduce TB volume and improve sleep parameters in OSA patients with TB narrowing. OSA patient with TB narrowing due to lingual tonsil hypertrophy shows greater therapeutic outcome and lingual tonsil hypertrophy appears to be most favorable surgical indications of robot-assisted TBR.

Lingual tonsil lymphatic tissue regrowth in patients undergoing transoral robotic surgery

OBJECTIVES/HYPOTHESIS

To evaluate a possible regrowth of lingual tonsil lymphatic tissue in patients submitted to lingual tonsil resection with transoral robotic surgery (TORS).

STUDY DESIGN

Retrospective Study.

METHODS

Medical records of patients surgically treated by means of TORS to remove excessive lymphatic tissue of the lingual tonsil were retrospectively reviewed. Postoperative endoscopic data after long-term follow-up were analyzed to investigate possible lymphatic tissue regrowth. Preoperative and postoperative lingual tonsil lymphatic tissue were classified according to the standardized Friedman's grading scale ranging from 0 to 4.

RESULTS

Sixty-eight patients (41 male and 27 female; mean age = 51.3 years) were considered suitable for the study analysis. Clinical regrowth was observed in six (8.8%) patients: four (5.9%) and two (2.9%) patients with grade 2 and 3 lymphatic hypertrophy, respectively. No correlation between the grade of regrowth, the time interval from surgery, and the volume of lymphatic tissue removed was found.

CONCLUSIONS

The lymphatic tissue regrowth after TORS resection appears to be very low.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:2652-2657, 2019.

Volumetric Tongue Reduction for Obstructive Sleep Apnea

Surgery for obstructive sleep apnea/hypopnea syndrome (OSA) is not a substitute for continuous positive airway pressure (CPAP) but is a salvage procedure for those who failed CPAP and other conservative therapies and therefore have no other options. The hypopharyngeal/tongue base procedures for the treatment of OSA are usually challenging to most sleep surgeons. In recent years, several procedures for OSA patients with hypopharyngeal obstructions have been developed to achieve higher response rates with decreased postoperative morbidities.

Long-term swallowing performance following transoral robotic surgery for obstructive sleep apnea

OBJECTIVES/HYPOTHESIS

This study aimed to evaluate the long-term swallowing performance following transoral robotic surgery (TORS) to the base of tongue (BOT) in the treatment of obstructive sleep apnea (OSA).

STUDY DESIGN

Retrospective and prospective cohort study.

METHODS

Data analysis of 39 patients who underwent BOT reduction via TORS to treat OSA at our center from September 2013 to April 2016. Long-term swallowing functions were assessed using subjective self-evaluated swallowing disturbances questionnaire (SDQ) and objective fiberoptic endoscopic evaluation of swallowing (FEES).

RESULTS

Seven patients underwent TORS BOT reduction alone, whereas 32 had also uvulopalatoplasty ± tonsillectomy, with a surgical success rate of 71.4%. Mean time for swallowing evaluation was 27.4 ± 9.43 months. Twenty-five patients completed the SDQ with an average score of 9.26 ± 10.05. In 32%, the SDQ was positive for dysphagia. In 10 out of 14 patients who underwent FEES, swallowing problems were noticed. The most common pathological findings were food residue in the vallecula followed by early spillage of food into the hypopharynx, penetration of solid food and liquid on the vocal folds surface, and aspiration.

CONCLUSIONS

BOT reduction via TORS has a negative effect on long-term swallowing function. A self-assessment questionnaire can help detect patients who suffer from swallowing impairment. Postoperative objective swallowing tests are essential not only in the immediate postoperative period but also during late routine follow-up. Proper patient selection and detailed information about surgery and possible late-swallowing effect are important factors before scheduling BOT reduction via TORS for OSA treatment.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:422-428, 2019.

Transoral robotic surgery of the tongue base for obstructive sleep apnea: Preliminary results

INTRODUCTION

Obstructive sleep apnea syndrome (OSAS) is a major public health issue. Robotic tongue-base reduction surgery is being developed, but needs assessment. The present study reports clinical and polygraphic results at 6 months' follow-up.

METHOD

Single-center prospective study of 8 patients undergoing transoral robotic surgery (TORS) for severe OSAS.

RESULTS

Mean age was 47 years. M/F sex ratio was 5:3. Initial body-mass index ranged from 18 to 35kg/m². Mean Epworth score was 12. Mean preoperative apnea-hypopnea index (AHI) was 47 (range, 36-60). At 6 months, only 1 patient did not meet usual success criteria (AHI<20 with>50% decrease); 2 patients had residual AHI between 10 and 20; the other 5 had non-significant event rates.

CONCLUSION

TORS tongue-base reduction showed promising results, which need confirmation on long-term multicenter studies.

Palatal surgery in a transoral robotic setting (TORS): preliminary results of a retrospective comparison between uvulopalatopharyngoplasty (UPPP), expansion sphincter pharyngoplasty (ESP) and barbed repositioning pharyngoplasty (BRP)

It has become increasingly clear in the past decade that surgical management of obstructive sleep apnoea hypopnoea syndrome (OSAHS) is most successfully managed with multilevel surgery. We evaluated the outcomes of multilevel interventions comparing three different palatal techniques added to TORS: uvulopalatopharyngoplasty (UPPP), a modified expansion sphincter pharyngoplasty (ESP), inspired by the Pang expansion sphincter pharyngoplasty technique and the latest barbed repositioning pharyngoplasty (BRP). Thirty patients were retrospectively evaluated. Ten patients underwent UPPP by Fairbanks, 10 BRP and 10 a modified ESP already described. All patients underwent TORS, tonsillectomy and septo-turbinoplasty. For all cases, the following data were retrieved and revaluated: preoperative and postoperative apnoea-hypopnoea index (AHI), preoperative and postoperative Epworth Sleepiness Scale (ESS), pain visual analogue scale (VAS; 0–10) for the first 5 days postoperatively, palatal operative time for each surgical technique, discharge date and complication types and rate. Both BRP and ESP resulted in better postoperative AHI values and higher surgical success rates in comparison with UPPP. On the other hand, BRP was not more effective than ESP. ESP surgery time was significantly higher than UPPP, while BRP was the quickest procedure. In summary, ESP and BRP seem to be more effective than UPPP in a multilevel surgical robotic setting. However, being quicker, easy to learn and with a low rate of complications, BRP is a safe, effective and promising option for treatment of OSAHS patients.

Transoral robotic resection of benign tumors of the upper aerodigestive tract: Experience of the French group of GETTEC

BACKGROUND

The purpose of this study was to assess the current use of transoral robotic surgery (TORS) in benign tumors of the upper aerodigestive tract through a case series and a literature review.

METHODS

This multicentric retrospective study was conducted in 6 French centers between November 2009 and July 2017.

RESULTS

Twenty-one patients had a TORS resection of a tumor at varied locations with differing histopathologic characteristics. The mean postoperative hospital stay was 6.1 days. Eight patients had nasogastric tubes, which were removed after a mean of 5.6 days. Two patients had a prophylactic tracheostomy for an average of 5.5 days. A third tracheostomy was performed secondarily for postoperative bleeding. No recurrences were observed during the 2-year follow-up.

CONCLUSION

This technique caused few complications and resulted in short hospitalization, with satisfactory functional and recurrence outcomes. However, the risk of bleeding and edema must be considered, and the need for a tracheostomy must be approached wisely.

Robotics in otorhinolaryngology - head and neck surgery

A look at the past, present and future.

Trans-Oral Robotic Tongue Reduction for OSA: Does Lingual Anatomy Influence the Surgical Outcome?

STUDY OBJECTIVES

To evaluate both the influence of the volume of the excised base of tongue (BOT) on the surgical outcome after robotic tongue reduction in patients affected by obstructive sleep apnea (OSA) and the role of the lymphatic or muscular predominance within the removed tissue.

METHODS

Fifty-one patients with OSA were included in this study. All patients were treated with a robotic tongue base reduction. Data registered for the analysis were: age, sex, preoperative body mass index, preoperative and postoperative apnea-hypopnea index (AHI), delta AHI (preoperative AHI - postoperative AHI), total volume of the excised BOT, total thickness of excised BOT, isolated lymphatic thickness and soft tissue thickness (including muscular component) of the excised BOT, and lymphatic/soft tissue ratio (lymphatic thickness / soft tissue thickness).

RESULTS

A statistically significant reduction of AHI values was seen postoperatively, and a success rate of 74.5% was recorded. However, no significant correlations between delta AHI and tongue volume in cubic centimeters, lymphatic/soft tissue ratio, and total thickness were found.

CONCLUSIONS

These findings reinforce the general opinion that OSA is not only influenced by anatomic factors but other phenomena may play a fundamental role in its genesis. A deeper understanding of OSA pathogenesis is needed in order to tailor an individual treatment strategy that could lead to a more effective therapy.

[Robotic Surgery - Who is The Boss?]

In the head and neck region, great potential is seen in robot-assisted surgery (RAS). Mainly in cancer surgery, the use of robotic systems seems to be of interest. Until today, two robotic systems (DaVinci® und FLEX®) have gained approval for clinical use in the head and neck region, and multiple other systems are currently in pre-clinical testing. Although, certain groups of patients may benefit from RAS, no unbiased randomized clinical studies are available. Until today, it was not possible to satisfactorily prove any advantage of RAS as compared to standard procedures. The limited clinical benefit and the additional financial burden seem to be the main reasons, why the comprehensive application of RAS has not been realized so far.This review article describes the large variety of clinical applications for RAS in the head and neck region. In addition, the financial and technical challenges, as well as ongoing developments of RAS are highlighted. Special focus is put on risks associated with RAS and current clinical studies. We believe, that RAS will find its way into clinical routine during the next years. Therefore, medical staff will have to increasingly face the technical, scientific and ethical features of RAS.

Transoral robotic surgery for obstructive sleep apnea syndrome: Principles and technique

Objective

The present study is a review of transoral robotic surgery (TORS) for the treatment of obstructive sleep apnea-hypopnea syndrome (OSAHS).

Methods

The review presents the experience of the robotic center that developed the technique with regards to patient selection, surgical method, and post-operative care. In addition, the review provides results of a systematic review and meta-analysis of the complications and clinical outcomes of TORS when applied in the management of OSAHS.

Results

The rate of success, defined as 50% reduction of pre-operative AHI and an overall AHI <20 events/h, is achieved in up to 76.6% of patients with a range between 53.8% and 83.3%. The safety of this approach is reasonable as the main complication (bleeding) affected 4.2% of patients (range 4.2%–5.3%). However, transient dysphagia (7.2%; range 5%–14%) does compromise the quality of life and must be discussed with patients preoperatively.

Conclusions

TORS for the treatment of OSAHS appears to be a promising and safe procedure for patients seeking an alternative to traditional therapy. Appropriate patient selection remains an important consideration for successful implementation of this novel surgical approach requiring further research.

Robotic microlaryngeal phonosurgery: Testing of a "steady-hand" microsurgery platform

OBJECTIVES/HYPOTHESIS

To evaluate gains in microlaryngeal precision achieved by using a novel robotic "steady hand" microsurgery platform in performing simulated phonosurgical tasks.

STUDY DESIGN

Crossover comparative study of surgical performance and descriptive analysis of surgeon feedback.

METHODS

A novel robotic ear, nose, and throat microsurgery system (REMS) was tested in simulated phonosurgery. Participants navigated a 0.4-mm-wide microlaryngeal needle through spirals of varying widths, both with and without robotic assistance. Fail time (time the needle contacted spiral edges) was measured, and statistical comparison was performed. Participants were surveyed to provide subjective feedback on the REMS.

RESULTS

Nine participants performed the task at three spiral widths, yielding 27 paired testing conditions. In 24 of 27 conditions, robot-assisted performance was better than unassisted; five trials were errorless, all achieved with the robot. Paired analysis of all conditions revealed fail time of 0.769 ± 0.568 seconds manually, improving to 0.284 ± 0.584 seconds with the robot (P = .003). Analysis of individual spiral sizes showed statistically better performance with the REMS at spiral widths of 2 mm (0.156 ± 0.226 seconds vs. 0.549 ± 0.545 seconds, P = .019) and 1.5 mm (0.075 ± 0.099 seconds vs. 0.890 ± 0.518 seconds, P = .002). At 1.2 mm, all nine participants together showed similar performance with and without robotic assistance (0.621 ± 0.923 seconds vs. 0.868 ± 0.634 seconds, P = .52), though subgroup analysis of five surgeons most familiar with microlaryngoscopy showed statistically better performance with the robot (0.204 ± 0.164 seconds vs. 0.664 ± 0.354 seconds, P = .036).

CONCLUSIONS

The REMS is a novel platform with potential applications in microlaryngeal phonosurgery. Further feasibility studies and preclinical testing should be pursued as a bridge to eventual clinical use.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:126-132, 2018.