Use of Indocyanine Green Fluorescence During Total Thyroidectomy to Identify Parathyroid Glands and Prevent Hypoparathyroidism.

INTRODUCTION: Total thyroidectomy is associated with a high rate of transient or permanent hypoparathyroidism. During surgery, indocyanine green (ICG) fluorescein angiography can be used to detect and preserve well-vascularized parathyroid glands. This technique has been introduced as an intraoperative support to prevent postoperative hypoparathyroidism. MATERIAL AND METHODS: One-hundred consecutive patients who had undergone total thyroidectomy were included in this study. Autofluoroscopy was used on the first dominant side of thyroidectomy and to identify the contralateral parathyroid glands. An intravenous bolus of 5 mg ICG (VERDYE, Diagnostic Green GmbH, Aschheim-Dornacht, Germany) was administered once. ICG fluorescein angiography was used as a "bridge" at the end of the first dominant hemithyroidectomy and after exposure of the parathyroid glands on the second side. This allowed us to (i) determine the vascularization of the first two parathyroid glands and (ii) define the blood vessels and thus the line of dissection of the parathyroid glands of the second resection side. Finally, autofluoroscopy was then applied outside the surgical area on the surgical specimen to assess forgotten parathyroid glands, which should therefore be re-implanted. Autofluoroscopy and ICG fluorescein angiography were evaluated in real time using the same technology, i.e., FLUOBEAM® LX (EUROPE - Fluoptics Grenoble, France; USA - Fluoptics Imaging Inc., Cambridge, MA, USA). The study was approved by the local ethics committee. RESULTS: Autofluorescence and ICG fluorescein angiography were performed without any problems in all cases. A total of 370 parathyroid glands were detected in this series. ICG changed the surgical strategy for the first-side parathyroid glands in 5% of cases, i.e,. they were not well-vascularized and were re-implanted. The rate of transient hypoparathyroidism was 19%. The percentage of parathyroids in the surgical specimen was 3.5% and all were re-implanted during the same surgery. There was no case of postoperative definitive hypoparathyroidism when at least one parathyroid gland with a high fluorescence intensity was preserved on the first side of resection. CONCLUSION: Use of ICG fluorescein angiography may contribute to predicting and thus preventing postoperative definitive hypoparathyroidism after total thyroidectomy. The results of this case series confirm recent studies. Caution is advised when weakly perfused parathyroid glands are discovered.

3D Transoral Endoscopic Thyroid.

Transoral endoscopic thyroidectomy with vestibular approach (TOETVA) is a feasible new surgical procedure that does not require visible incisions. We describe our experience with three-dimensional (3D) TOETVA. We recruited 98 patients who were willing to undergo 3D TOETVA. Inclusion criteria were: (a) patients with a neck ultrasound (US) with an estimated thyroid diameter of 10cm or less; (b) estimated US gland volume ≤45ml; (c) nodule size ≤50mm; (d) benign tumor, such as thyroid cyst, goiter with one nodule, or goiter with multiple nodules; (e) follicular neoplasia; and (f) papillary microcarcinoma without evidence of metastases. The procedure is performed using a three-port technique at the oral vestibule, a 10mm port for the 30° endoscope, and two additional 5mm ports for dissecting and coagulation instruments. The CO2 insufflation pressure is set at 6mmHg. An anterior cervical subplatysmal space is created from the oral vestibule to the sternal notch and laterally to the sternocleidomastoid muscle. Thyroidectomy is performed entirely 3D endoscopically with conventional endoscopic instruments and intraoperative neuromonitoring. There were 34% total thyroidectomies and 66% hemithyroidectomies. Ninety-eight 3D TOETVA procedures were successfully performed without any conversions. The mean operative time was 87.6 minutes (59-118 minutes) for lobectomy and 107.6 minutes (99-135 minutes) for bilateral surgery. We observed one case of transient postoperative hypocalcemia. Paralysis of the recurrent laryngeal nerve did not occur. The cosmetic outcome was excellent in all patients. This is the first case series of 3D TOETVA.

Trans-oral endoscopic thyroidectomy vestibular approach (TOETVA) for the pediatric population: a multicenter, large case series.

INTRODUCTION: A cervical scar has been shown to have an impact on the quality of life of children undergoing thyroid surgery. Transoral endoscopic vestibular thyroidectomy via the vestibular approach (TOETVA) offers the absence of a cutaneous incision, and has not been described to date in the pediatric population. OBJECTIVE: To describe the first series of TOETVA in a pediatric population. PATIENTS AND METHODS: A retrospective, multicenter study, including all patients > 18 years old who underwent TOETVA. Data was prospectively collected and included demographics, preoperative ultrasound, cytology and indications for surgery. Intraoperative parameters included length of surgery and complications, with final pathology and postoperative course also reviewed. TOETVA surgical success was defined as completion of surgery via this approach. RESULTS: Forty-eight children were included. Of these, 43 (89.5%) were girls. The median age was 16 years (range 10-17). The most common indication for surgery was a benign thyroid nodule (n = 26, 54.1%). Eleven patients (22.9%) had papillary thyroid carcinoma on final pathology, of which 90.9% (10/11) were diagnosed pre-operatively based on FNA cytology. Hemithyroidectomy was performed in 36 patients (75%). All surgeries were completed endoscopically. The mean malignant tumor size was 1.4 ± 0.4 cm and all tumors were completely excised with clean margins. No permanent complications were documented. A single patient (2.1%) had transient RLN injury (1.6%, 1/60 nerves at risk). Transient hypocalcemia was documented in 4 of the 12 patients undergoing total thyroidectomy (33.3%). Transient mental nerve injury/chin hypoesthesia was documented in 2 patients (4.2%). CONCLUSIONS: TOETVA appears to be a feasible and safe approach for thyroidectomy in the pediatric population in carefully selected cases, and may be discussed with patients and parents as an alternative for the trans-cervical approach.

Conventional Total Thyroidectomy Using a Novel Single Retractor: Technical Note for Apollo®.

Despite the increasingly innovative techniques developed in thyroid surgery to offer patients minimally invasive and scarless interventions, conventional open procedures still account for most of the interventions performed in this field. The surgical incision length has been significantly reduced, from 6-9 cm to 3 cm, and therefore patients perceive the scar to be highly acceptable. In this technical note, we present the use of a new single retractor (APOLLO®; AFS MEDICAL GmbH, Teesdorf, Austria) for conventional open thyroidectomies with intraoperative neuromonitoring. This device offers several advantages: a) better exposure of the surgical field; b) less traction on skin flaps and neck muscles; and c) protection of the skin edges from the heat generated by energy-based devices/coagulating instruments, with consequent better healing.

Transoral robotic thyroidectomy versus transoral endoscopic thyroidectomy: a propensity-score-matched analysis of surgical outcomes.

BACKGROUND: Transoral endoscopic thyroidectomy vestibular approach (TOETVA) has been shown to be safe and has similar outcomes as open thyroidectomy for selected patients. It is not clear if transoral robotic thyroidectomy (TORT) may extend transoral endoscopic thyroidectomy to more complex thyroid operations. The study aimed to compare the safety and outcomes of TORT with those of TOETVA. METHODS: We retrospectively reviewed all patients who had TORT and TOETVA performed by a single surgeon from June 2017 to May 2019. Intrathoracic goiter and combined operations were excluded. Surgical outcomes were compared after propensity score matching. Learning curves, as measured by operating time, were evaluated. RESULTS: A total of 150 patients underwent 154 transoral (55 TORT and 99 TOETVA) thyroidectomy. Of the 154 operations, 28 (18.2%) were bilateral total thyroidectomy and 126 (81.8%) were unilateral thyroid lobectomy. After propensity score matching, we found a longer operative time (median [interquartile range]) for TORT (n = 53) than for the TOETVA (308 [284-388] vs 228 [201-267] min, P < 0.001). Blood loss and visual analog scale scores for pain were not significantly different between the two groups. Central neck lymph node dissection was performed more frequent in the TORT group (28 of 53 [52.8%] vs 10 of 53 [18.9%], P = 0.001), and when performed, the numbers of total and positive lymph nodes did not differ significantly between the two groups. The rates of hypoparathyroidism and recurrent laryngeal nerve injury did not differ significantly between the two groups. There was no conversion to open thyroidectomy, mental nerve injury, or surgical site infection. The learning curve for TORT was 25 cases, but no obvious learning curve was observed for TOETVA. CONCLUSIONS: TORT requires a longer operative time, but is as safe as TOETVA and may be useful for more complex thyroid operations.

Prevention of non-recurrent laryngeal nerve injury in robotic thyroidectomy: imaging and technique.

INTRODUCTION: The aim of this report was to summarize observations, evaluate the feasibility, provide detailed information concerning proper techniques, and address limitations for non-recurrent laryngeal nerve (NRLN) dissection and release during the robotic bilateral axillo-breast approach (BABA) for thyroidectomy. MATERIALS AND METHODS: The BABA approach was used in two cases of thyroidectomy in the setting of NRLN. Preoperative CT imaging findings suggesting the aberrant anatomy are reviewed and technical planning, inclusive of intraoperative nerve monitoring, was employed. Intraoperative videos with narrative discussion of technique for safe dissection are provided, along with supplementary video of additional technical guidance. RESULTS: In both cases, the NRLNs were identified, dissected, and preserved. We dissected the proximal segment of each NRLN to its origin. We determined that the use of only the NRLN proximal to distal robotic dissection jeopardized the nerve. The BABA approach with the Type I NRLN is similar to the dissection of the recurrent laryngeal nerve (RLN) in transoral thyroidectomy. Due to interference with endoscopic viewing caused by the thyroid cartilage, the Type I NRLN is more challenging to manage both at the laryngeal entry point and its origin from the vagus nerve (VN). For the Type II NRLN, it is essential to identify its point of origin and the reflection of the nerve from the VN. Therefore, modification of nerve dissection to mirror open surgery with bidirectional nerve dissection assisted in avoidance of traction injury to the nerve. CONCLUSIONS: We presented a video, a detailed description of methods, and discussed limits for NRLN management in robotic BABA. This report included (i) a description of the aberrant anatomy and CT scans to inform surgeons of the possible NRLN locations, (ii) a description of a technique for using the nerve monitor in the robotic surgeries, and (iii) a description of the techniques used to isolate and protect the NRLN during the robotic surgery. In robotic BABA, our NRLN-sparing technique and degree included mainly a multi-directional nerve dissection (i.e., medial-grade, later-grade approach together with proximal to/from distal) using athermal technique. The NRLN-sparing technique is predominantly carried out in an anterior dissection plane.

Transoral robotic thyroidectomy versus conventional open thyroidectomy: comparative analysis of surgical outcomes using propensity score matching.

BACKGROUND: Various approaches for thyroid surgery became possible with the use of robotic systems. Transoral robotic thyroidectomy (TORT) is one of the newest approaches and draws attention because of its cosmetic excellence. In this study, we compared the surgical outcomes of TORT and conventional open thyroidectomy (OT). METHODS: We retrospectively reviewed and compared the medical records of consecutive patients who underwent TORT or OT for thyroid carcinoma from March 2009 to January 2018. Propensity score matching using 10 clinico-pathologic factors was used to generate two matched cohorts, each composed of 186 patients. RESULTS: The study included 372 patients who underwent TORT (n = 186) or OT (n = 186). Mean age, tumor size, and gender were not different between both groups. The two groups showed similar surgical outcomes, except for a longer operative time for TORT. There was one patient with immediate postoperative bleeding in the TORT group. The patient underwent re-operation for hemostasis with endoscopic approach. In the OT group, one patient had wound seroma, which was treated by several rounds of needle aspiration without infection. Vocal cord palsy was present in one patient in the TORT group, which was recovered in 3 months. CONCLUSIONS: TORT could be performed safely and had comparable surgical outcomes with OT in the selected patients. TORT may be a suitable operative alternative for patients who do not want to leave scars on the neck.

Transoral Thyroidectomy: Safety and Outcomes of 200 Consecutive North American Cases.

BACKGROUND: North American adoption of the transoral endoscopic thyroidectomy vestibular approach (TOETVA) has been limited due to concerns regarding the generalizability of published outcomes, as data are predominantly from Asian cohorts with a different body habitus. We describe our experience with TOETVA in a North American population in the context of the conventional transcervical approach thyroidectomy (TCA). STUDY DESIGN: Cases of TOETVA and TCA were reviewed from August 2017 to March 2020 at a tertiary care center. Outcomes included operative time, major (permanent recurrent laryngeal nerve (RLN) injury, permanent hypoparathyroidism, hematoma, conversion to open surgery), and minor complications. The TOETVA cohort was stratified into body mass index (BMI) classes of underweight/normal < 25 kg/m2, overweight 25-29.9 kg/m2, and obese ≥ 30 kg/m2 for comparative analysis. Multivariable logistic regression analyses were performed for odds of cumulative complication. RESULTS: Two hundred TOETVA and 333 TCA cases were included. There was no difference in incidence of major complications between the TOETVA and TCA cohorts (1.5% vs. 2.1%, p = 0.75). No difference was found in the rate of temporary RLN injury (4.5% vs. 2.1%, p = 0.124) or temporary hypoparathyroidism (18.2% vs. 12.5%, p = 0.163) for TOETVA and TCA, respectively. Surgical technique (TOETVA vs TCA) did not alter the odds of cumulative complication (OR 0.69 95% CI [0.26-1.85]) on logistic regression analysis. In the TOETVA cohort, higher BMI did not lead to a significantly greater odds of cumulative complication, 0.52 (95% CI [0.17-1.58]) and 1.69 (95% CI [0.74-3.88]) for the overweight and obese groups, respectively. CONCLUSION: TOETVA can be performed in a North American patient population without a difference in odds of complication compared to TCA. Higher BMI is not associated with greater likelihood of complication with TOETVA.

Drawbacks of neural monitoring troubleshooting algorithms in transoral endoscopic thyroidectomy.

INTRODUCTION: The application of intraoperative neural monitoring (IONM) trouble-shooting algorithms procedures in transoral endoscopic thyroidectomy vestibular approach (TOETVA) was investigated. METHODS: Loss of signal (LOS) is defined as a loss of the primary electromyographic (EMG) normal biphasic waveform with reduced amplitude response to less than 100µV with a stimulation level intensity of 1-2mA. A systematic review of the IONM system at LOS was covered methodically: (i) correct endotracheal tube verification, (ii) stimulation of the recurrent laryngeal nerve (RLN) at entry point, (iii) ipsilateral or contralateral vagal nerve (VN) stimulation, and (iv) laryngeal twitch (LT). RESULTS: The function of 223 nerves at risk (NAR) was recorded with IONM. Twenty-seven (12%) NAR experienced a suspected LOS. LT could not be appreciated. In 15/27 (55%) cases, the application of the IONM trouble-shooting algorithm revealed upward displacement of the EMG tube (all orotracheal intubations). In 9 (4%) NAR, VN stimulation was not accomplished. In detail, there were n.5 left and n. 4 right VNs. Two VNs were ipsilateral, and 7 VNs contralateral. For EMG tube displacement, because the oral/nasal area is included in the aseptic field, it is less possible to re-check by the laryngoscope or fiberscope. CONCLUSIONS: A limit for applying the IONM trouble-shooting algorithm to TOETVA is determined by (a) inability to appreciate the LT, (b) difficulty in stimulating the ipsilateral and contralateral VN, and (c) remodeling EMG endotracheal tube position. A modified IONM trouble-shooting algorithm for TOETVA is proposed.

Use of Vivostat® Autologous Fibrin Sealant in Thyroid Surgery.

INTRODUCTION: Post-thyroidectomy hemorrhage is a rare but potentially life-threatening and unpredictable complication of thyroid surgery. Therefore, intraoperative bleeding control and hemostasis are crucial. However, the most efficient, cost-effective, and standardized way to achieve this is not clear. This study aimed to evaluate the outcome of total thyroidectomy (TT) and partial thyroidectomy (PT) performed using the Vivostat® hemostatic system (Vivostat A/S, Lillerød, Denmark). METHODS: Patients underwent TT and PT for benign and malignant diseases (multinodular goiter, Graves' disease, differentiated thyroid carcinoma). The primary endpoint was 1st-day postoperative drain output and bleeding that required reintervention. Secondary endpoints included surgery duration and postsurgical complications (vocal fold palsy, hypocalcemia, seroma, wound infection). RESULTS: Between October 2020 and December 2020, 56 patients were enrolled; 69.6% female; mean age 49.5 years. The mean 24-h drain output was 40 ml. No redo surgery was needed. Seroma was present in 5.3% of cases; no permanent vocal palsy or hypocalcemia was observed. CONCLUSION: This study shows that the Vivostat® system is both safe and effective for hemostasis during thyroid surgery.

C2 Xplore® for Intermittent and Continuous Laryngeal Nerve Monitoring: Technical Note.

Due to the direct anatomical relationship between the recurrent laryngeal nerve (RLN) and the thyroid gland, the function and anatomical integrity of the RLN is fundamentally at risk in every thyroid operation. While a RLN morbidity rate of less than 5% is achieved in specialized clinics, the morbidity rates are significantly higher in non-specialized centers. Thus, the aim is to reduce the complication rate by establishing standardized interventions. Exact knowledge of the anatomical course of the RLN, the nerve-sparing dissection technique and the supportive use of intraoperative neuro-monitoring (IONM) to identify anatomical variations are the basis for nerve-sparing surgery. We tested the new C2 Xplore® system (inomed Medizintechnik GmbH, Emmendingen, Germany) as a tool for performing intermittent and continuous laryngeal nerve monitoring during thyroid surgery. The C2 Xplore® helps to enhance surgeon-IONM interaction, and provides comprehensive digital EMG documentation with EMG quantification. EMG artifacts are removed. Image quality and EMG feedback are highly acceptable for intraoperative monitoring. The C2 Xplore® system does not have a deleterious impact on the proper function of other surgical instruments. C2 Xplore® is effective for intraoperative monitoring, optimizing RLN dissection, and supporting surgical deliberations, and for forensic use and research. A step-by-step C2 Xplore® procedure is described.

Status of Alternative Approaches for Thyroidectomy: Is There Any Evidence to Substitute in Place of Conventional Surgery?

Over the past 20 years, various alternative cervical minimally invasive (partly endoscopically assisted) and extracervical endoscopic (partly robot-assisted) approaches have been developed. All of these alternative access methods aim at optimizing the cosmetic results. In principle, the indication for the use of alternative access procedures does not differ from that for conventional surgery. Nonetheless, appropriate experience in traditional thyroid surgery and suitable patient selection, taking into account thyroid volumes and the underlying pathology, are important prerequisites. General contraindications for an alternative approach are large goiter with symptoms of compression, advanced thyroid carcinoma, recurrent interventions or previous radiotherapy in the operating area. The alternative surgical approaches to the thyroid can be divided into cervical minimally invasive, extracervical endoscopic (robot-assisted) and transoral procedures. This article gives an overview of the clinically used alternative approaches in thyroid surgery. The desire for an optimal cosmetic result should not be prioritized over patient safety. Only a few alternative procedures (minimally invasive video-assisted thyroidectomy, transaxillary robot-assisted thyroidectomy) can currently be viewed as a useful addition to conventional thyroid surgery, even when in responsible, experienced hands for a selected group of patients.

An Improved Recurrent Laryngeal Nerve-Monitoring Device: Technical Note for Nim Vital™.

A new device for monitoring the laryngeal nerves during thyroid surgery has been developed. NIM Vital™ (Medtronic Xomed, Inc., Jacksonville, FL, USA) incorporates (a) a new wireless design, (b) NIM NerveTrendTM (Medtronic Xomed) EMG reporting, (c) intelligent noise-reduction technology that suppresses artifacts, (d) smart troubleshooting pop-up alerts, and (e) NIM Nervassure ™ (Medtronic Xomed) for continuous monitoring. This device offers enhanced stability and flexibility for both intermittent and continuous laryngeal nerve monitoring. The new NIM NerveTrend ™ EMG reporting makes it possible to track the recurrent laryngeal nerve condition throughout a procedure, even when using intermittent nerve monitoring. During both continuous and intermittent monitoring, green, yellow and red status bars provide visual information and associated tones provide audible cues, making it easy to monitor nerve function and interpret EMG trends. This new tool for laryngeal nerve monitoring has the potential to augment nerve dissection during surgery. Measurements of long-term outcome are needed to establish their efficacy.

Does Tumor Size Affect Surgical Outcomes of Transoral Robotic Thyroidectomy for Patients with Papillary Thyroid Carcinoma? A Retrospective Cohort Study.

BACKGROUND: Transoral robotic thyroidectomy (TORT) for differentiated thyroid carcinoma is increasing in popularity. However, studies are limited to small tumors. This study aimed to compare the outcomes of TORT for papillary thyroid carcinomas smaller than 1 cm and 1 cm or larger. METHODS: The study analyzed 269 patients with papillary thyroid carcinoma who underwent TORT at Korea University Hospital, Korea between January 2001 and December 2017. Surgical outcomes and postoperative complications were compared. RESULTS: Group 1 (tumor < 1 cm) had 215 patients, and group 2 (tumor ≥ 1 cm) had 54 patients. The majority of the patients underwent lobectomy (95.8% in group 1 and 87.0% in group 2; p = 0.339) and unilateral central neck dissection (96.3% in group 1 and 88.9% in group 2; p = 0.024). The two groups did not differ significantly in terms of gender, age, body mass index, thyroiditis status, Da Vinci model. or operative procedure. The majority of the tumors in group 1 (73%) had T1a staging, whereas the majority of the tumors in group 2 were stage T1b or T3a (44.4% in each group; p = 0.000). Most of the patients in group 1 had N0 staging (59.1%), whereas most of the patients in group 2 had N1a staging (55.6%; p = 0.026). The mean operative time was significantly longer in group 2 (198.0 ± 34.2 min in group 1 vs. 215.7 ± 49.3 min in group 2; p = 0.015). The two groups did not differ significantly regarding length of stay, postoperative pain score, or thyroglobulin level. No patients experienced locoregional or distant recurrence. No statistically significant difference in overall complications was observed (p = 0.214). CONCLUSIONS: Transoral robotic thyroidectomy is a safe and effective procedure and may be a feasible option for patients with papillary thyroid carcinomas larger than 1 cm.

Strategies for superior thyroid pole dissection in transoral thyroidectomy: a video operative guide.

BACKGROUND: The dissection of the superior thyroid gland pole is challenging when using the in TransOral Endoscopic Thyroidectomy Vestibular Approach (TOETVA) due to (a) the cranio-caudal approach, (b) cranial-caudal view, and (c) the restriction of maneuverability inside the narrow neck air pocket. METHODS: In this paper and operative video guide, a series of TOETVA's tips and tricks are presented with an emphasis on the strategies for a safe approach to the superior thyroid gland pole structures. RESULTS: Management of the upper thyroid pole structures includes: (a) use of a 5 mm/30°-45° endoscope; (b) retraction ports up to the limit of the lower jaw edge; (c) lateral retraction of 1/3 of the cranial strap muscles; (d) isthmectomy; (e) cutting the sternothyroid muscle cranially for 1 cm; (f) retraction of the thyroid upwards and laterally; (g) monitoring the external branch of the superior laryngeal nerve, and (h) sealing individual vessel branches. CONCLUSION: Access to the superior thyroid pole space through the TOETVA approach presents some challenges, particularly when accessing thyroid vessels or nodules located or displaced more cranially. Strategies that enhance a critical view of the superior thyroid gland structures can protect them from damage and have the potential to improve the safety of the TOETVA and decrease potential conversion rates.

Functional Voice and Swallowing Outcome Analysis After Thyroid Lobectomy: Transoral Endoscopic Vestibular Versus Open Approach.

BACKGROUND: The transoral endoscopic thyroidectomy vestibular approach (TOETVA) is a scarless remote-access thyroidectomy technique. This study compared subjective and objective voice outcomes and swallowing outcomes of patients who underwent thyroid lobectomy using the TOETVA versus conventional open thyroidectomy (OT). METHODS: In addition to questionnaires, acoustic and aerodynamic analyses were performed to compare subjective and objective voice outcomes of the two groups. Swallowing outcome analyses were conducted using Swallowing Impairment Index-6 (SIS-6) scores. Assessments were performed preoperatively and 3 and 6 months after surgery. Propensity score matching was performed to compare the outcomes of the two groups. RESULTS: One hundred and two patients were included in this study (52 TOETVA and 50 OT). Excluding two patients who had vocal cord palsy and open conversion in the TOETVA group, 100 patients completed 3-month postoperative surveys. There were no significant differences between the groups in VAS, GRBAS, or VHI-10 scores at the preoperative and 3- and 6-month assessments. For both groups, there were no significant changes in acoustic or aerodynamic parameters during the 3-6-month postoperative period. The TOETVA group had lower SIS-6 scores at the postoperative 6-month assessment, but the SIS-6 scores after 12 months were similar between groups before and after propensity score matching. CONCLUSIONS: Following TOETVA lobectomy, there were no significant changes in voice outcomes 3 and 6 months after surgery, and the outcomes were comparable with those of OT. The TOETVA group also had swallowing outcomes that were comparable with the OT group.

Translational Study on Recurrent Laryngeal Nerve Temperature Susceptibility.

BACKGROUND: Recurrent laryngeal nerve (RLN) injury is the most common and serious complication after thyroid surgery. However, little is known about the temperature threshold leading to RLN injury. In this study, we investigated threshold temperatures that cause RLN injury during thyroid surgery using continuous intraoperative neuromonitoring in swine models. METHODS: Four pigs weighing 30 to 40 kg were used for this study. We applied automatic periodic stimulation to the vagus nerve and dissected the RLN. The operative field was then filled with water at various temperatures (1.9°C to 87.4°C). The threshold temperature was defined as the temperature measured before filling the operative field that was associated with adverse events (latency increase of more than 10% or amplitude decrease of more than 50%). Loss of signal was defined as the electromyography (EMG) signal disappearing and not recovering during 30 min of observation. RESULTS: The low and high threshold temperatures were 2.5°C and 81.5°C, respectively. There were no adverse events at surrounding temperatures between 5.9°C and 77.5°C. The EMG signals in the RLNs exposed to the low threshold temperatures recovered, and there was no loss of signal. In contrast, the RLNs that showed adverse events at the high threshold temperatures showed loss of signal and no recovery of EMG signals. CONCLUSIONS: The RLN was found to be resistant to cold injury, whereas surrounding temperatures above 81.5°C may cause permanent thermal injury to the RLN. The surrounding temperature should be controlled within the safe range during thyroid surgery to avoid RLN injury.

Transoral Robotic Thyroidectomy for Papillary Thyroid Carcinoma: Perioperative Outcomes of 100 Consecutive Patients.

BACKGROUND: Endoscopic transoral thyroidectomy is a recently introduced technique of remote access thyroidectomy. We previously reported the feasibility of the robotic approach (TORT). Nevertheless, experience to date is limited, with scant data on outcomes in patients with papillary thyroid carcinoma (PTC). METHODS: This was a retrospective analysis of prospectively collected data. Patients with PTC, who underwent TORT at a single center between March 2016 and February 2017, were analyzed. RESULTS: There were a total of 100 patients (85 women, 15 men) with a mean age of 40.7 ± 9.8 years, and a mean tumor size of 0.8 ± 0.5 cm. Nine patients underwent a total thyroidectomy, and 91 underwent a lobectomy. The operative time for a total thyroidectomy and lobectomy was 270.0 ± 9.3 and 210.8 ± 32.9 min, respectively. Ipsilateral prophylactic central neck compartment dissection was performed routinely with retrieval of 5.0 ± 3.6 lymph nodes. Perioperative morbidity was present in nine patients including transient recurrent laryngeal nerve palsy (n = 1), postoperative bleeding requiring surgical intervention (n = 1), zygomatic bruising (n = 2), chin flap perforation (n = 1), oral commissure tearing (n = 2), and chin dimpling (n = 2). There was no conversion to endoscopic or conventional open thyroid surgery. CONCLUSION: In this study, TORT could be safely performed in a large series of patients with PTC without serious complications. In selected patients, TORT by experienced surgeons could be considered an alternative approach for remote access thyroidectomy.

New Paradigms for Neural Monitoring in Thyroid Surgery.

Intraoperative neuromonitoring (IONM) in thyroid gland surgery provides real-time feedback to the endocrine surgeon regarding the electrophysiological consequences of surgical manipulation of the laryngeal nerves. The goal of monitoring modalities is to detect surgical or physiological insults to the recurrent laryngeal nerve (RLN) while they are still reversible or, in cases where prevention is not an option, to minimize the damage done to these structures during thyroidectomy. In recent decades, monitoring of the RLN has become a fundamental part of endocrine surgery. IONM is a feasible procedure in both open and endoscopic, robotic thyroidectomy. Experts in IONM have organized a working group of general, endocrine, head and neck ENT surgeons and endocrinologists (International Neural Monitoring Study Group; INMSG) to develop standards for practicing this technique in endoscopic and robotic thyroidectomy. This paper presents recent clinical and research experience with intraoperative neural monitoring for thyroid gland surgery.

A comparison study of the transoral and bilateral axillo-breast approaches in robotic thyroidectomy.

OBJECTIVES: Transoral robotic thyroidectomy (TORT) is a new remote access approach to avoid cervical incision. The purpose of this study is to compare two approaches used to avoid cervical incision: transoral approach and bilateral axillo-breast approach (BABA) in robotic thyroidectomy. METHODS: A total of 90 patients were enrolled prospectively between September 2016 and April 2017. The BABA group had 43 and the TORT group had 47 patients, respectively. Parameters including clinicopathologic data, operative time, complications, laboratory data, hospital stay, postoperative pain, and cosmetic satisfaction were analyzed. RESULTS: Complications were not different among the two groups. The operative time of TORT was longer than BABA until 15 cases of TORT were completed, but there was no difference after that. The Visual Analogue Scale score in TORT was lower than BABA in all the periods. TORT showed a higher cosmetic satisfaction after surgery. There was no infection or permanent mental nerve hypoesthesia in TORT. CONCLUSION: Our study showed that TORT had less postoperative pain and a greater cosmetic satisfaction than the BABA. There were no significant differences in the postoperative surgical results between the two groups. TORT was comparable to the BABA in outcome with higher cosmetic satisfaction and less pain.