Evidence-based review series on endoscopic thyroidectomy: real progress and future trends

Endoscopic Thyroidectomy for Large-Sized Goiters: Merits of the Axillo-Breast Approach with Gas Insufflation

Background

Several minimal access approaches to the thyroid gland have been widely applied; nevertheless, such approaches are still challenging when dealing with large-sized thyroid nodules or goiters. We hereby evaluated the outcomes and highlighted the merits of endoscopic axillo-breast hemithyroidectomy (EABH) for large-sized unilateral goiters.

Methods

Patients underwent EABH for unilateral large thyroid nodules ≥6 cm in its greatest dimension or unilateral large goiter (≥60 ml sonographic volume) whatever the size of its contained nodules were identified from a prospectively maintained database. Their demographic data, clinicopathological profiles, and surgical and esthetic outcomes are reported and analyzed.

Results

Over a 2-year period, 33 patients matched the selection criteria. Their mean age was 34.75 ± 11.39 years. There were 30 women and 3 men. The majority of nodules were radiologically TIRADS3 and cytologically Bethesda 3. The mean sonographic dominant nodule greatest dimension was 5.29 ± 1.48 cm (range: 3-9.5 cm). The mean sonographic volume of the pathological lobe was 101.86 ± 54.45 ml (range: 60.11-236.88 ml). All cases were completed endoscopically with no conversion to open. The mean operative time was 110.76 ± 18.75 minutes. No significant postoperative complications were reported except for one case with temporary vocal cord paresis. Most (87.9%) of the patients were extremely satisfied with the procedure.

Conclusion

EABH with our suggested key steps could be considered an effective valid approach for unilateral large goiters in trained hands and in patients desirous for cosmesis.

Minimally Invasive Approaches for Thyroid Surgery-Pitfalls and Promises

PURPOSE OF REVIEW

To provide an overview of the feasibility and safety of current minimally invasive remote-access approaches for thyroid surgery, in view of the amounting new challenges and paradigm shifts in the management of thyroid pathologies.

RECENT FINDINGS

Over the past two decades, several remote-access approaches for thyroid surgery have been developed to improve cosmesis; however, none has been widely adopted extensively in the Western world. The recently emerged transoral endoscopic thyroidectomy via vestibular approach (TOETVA) is the only true minimally invasive approach, completely avoiding skin incisions. It has a relatively short learning curve, midline surgical view, accessible surgical equipment, and relatively broad inclusion criteria with promising surgical outcomes as reported to date. TOETVA has proven to be safe and feasible for carefully selected patients. Further experience and long-term follow-up are needed to define the added value of TOETVA except for improved cosmetic outcome.

Minimally invasive video-assisted thyroidectomy (MIVAT)

Background

Minimally invasive video-assisted thyroidectomy (MIVAT) was first described in 1999 and it has become a widespread technique performed worldwide. Although initially limited to benign thyroid nodules, MIVAT was progressively adopted for all types of thyroid diseases, while remaining within the selection criteria. It is reported that, in selected cases, MIVAT is comparable to standard open thyroidectomy (SOT) in terms of oncologic radicality, time, costs and complications rate, with the advantage of a better cosmetic result and a lower post-operative pain.

Methods

The authors conducted a retrospective analysis about patients who underwent MIVAT between 1998 and 2019 in the Endocrine Surgery Unit of the University Hospital in Pisa. Indications and contraindications are mentioned and strictly followed.

Results

Total thyroidectomy was performed in 1,862 cases (69%) and hemithyroidectomy was performed in 763 cases (28.3%). Conversion occurred in 43 cases (1.6%). In 188 cases (7%) a postoperative transient hypoparathyroidism was reported, whereas definitive hypoparathyroidism was reported in 12 cases (0.4%). Thirty-eight patients (1.4%) suffered from a definitive postoperative recurrent laryngeal nerve palsy. No definitive bilateral recurrent laryngeal nerve palsy occurred.

Conclusions

From our multi-years' experience which spreads over 20 years, we can reaffirm the concept that MIVAT is a safe procedure which is not burdened by an increase complications rate or additional costs. Furthermore, this technique offers advantages in terms of cosmetic results and post-operative pain.

Indications, benefits and risks of transoral thyroidectomy

The advancement of minimally invasive surgery in the field of endocrine surgery over the last 2 decades has fostered the attempt of natural orifice transluminal endoscopic surgery (NOTES) for thyroidectomy and parathyroidectomy via oral incisions. This technically demanding surgery is currently being evaluated in a number of specialised centres. The procedure has gained popularity worldwide and is performed in more than 50 centres. By retrieving information from published or presented articles and direct personal communications, this study reports several issues to enable and optimise correct patient and surgeon candidacy, present the advantages and prevent novel complications under the standards of open thyroid surgery. Not all patients are eligible for the transoral approach. Transoral endoscopic and robotic procedures were described and critically analysed in this study.

Intraoperative Neural Monitoring in Endoscopic Thyroidectomy Via Bilateral Areola Approach

OBJECTIVE

The aim of this report was dual: (a) to describe the step by step standardized intraoperative neural monitoring (IONM) procedure for recurrent laryngeal nerve (RLN) and external branch of the superior laryngeal nerve focusing on percutaneous IONM method, and (b) evaluation and outcomes of intermittent IONM in 237 endoscopic thyroidectomy via bilateral areolar approach cases.

MATERIALS AND METHODS

A 10-mm curved incision is made along the margin of the right areola at the 2 to 4 o'clock position for the 30-degree endoscope. Bilaterally 5-mm incisions are required on the edges of the areola at the 11 to 12 o'clock positions as accessory operating ports. Ball-tip, monopolar, single-use, standard stimulating probe with a 10-cm handle and 9-cm shaft is adopted percutaneously for IONM. As reference, on the dominant thyroid lesion side, a 0.5-cm circle is drawn with the center at the intersection of a line 2-cm lateral to the anterior median line and a line 2-cm above the line connecting the bilateral clavicular heads. After ensuring with ultrasonography that no vessels are within the puncture passage, the skin is pierced with an 18-G syringe needle. After withdrawing the needle, the probe is carefully inserted through the tract. IONM is performed according to standards of equipment set up, anesthesia, tube positioning verification tests, and electromyography determinations.

RESULTS

A total of 277 nerves at risk were favorably monitored with percutaneous probe stimulation. RLN, vagus nerve, and external branch of the superior laryngeal nerve were successfully determined. There were no instances of IONM malfunction, equipment displacement, or interference with the other endoscopic instruments. IONM probe insertion incision determined no scarring or morbidity in the neck. The incidence of RLN monolateral temporary palsy was 6%.

CONCLUSIONS

Standardized monitoring in endoscopic thyroidectomy via bilateral areolar approach is feasible. IONM was implemented by means of percutaneous stimulating probe.

Transoral endoscopic thyroidectomy via a vestibular approach: why and how?

The transoral endoscopic thyroidectomy vestibular approach (TOETVA) is a novel, scar-free surgical procedure that does not require visible incisions. Indications for TOETVA are as follows: predicted gland width on diagnostic imaging ≤10 cm; a thyroid volume outline of <45 mL or dominant nodule dimension of ≤50 mm; three or four Bethesda lesions; a primary papillary microcarcinoma without local or distant metastasis; and patient request for optimal esthetic results. Contraindications are as follows: patients unfit for general anesthesia; precedent radiation in the head, neck, upper mediastinum; antecedent neck surgery; recurrent goiter; a gland volume of >45 mL or main nodule diameter of >50 mm; and documentation of lymph node or distant metastases, tracheal/esophageal infiltration, preoperative laryngeal nerve palsy, hyperthyroidism, mediastinal goiter, or an oral abscess. Patients with poorly differentiated or un-differentiated cancer, dorsal extrathyroidal radius, and/or lateral neck metastasis are not suitable for TOETVA. Following the introduction of a robotic surgical system, enabling a three-dimensional surgical view and the use of articulating instruments, TOETVA became suitable for most differentiated thyroid cancers without evidence of extensive extrathyroidal invasion or lateral neck metastasis. The procedure is performed using a vestibular approach and three-port technique; a 10-mm port is used for the 30° endoscope, two 5-mm ports are used for the dissecting and coagulating instruments, and an 8-mm port is placed in the axillary fold during the robotic procedure to enhance fine countertraction of tissue for radical oncological dissection. TOETVA follows surgical planes and is probably the best scar-free approach to the thyroid, given the short distance between the gland and intraoral incisions.

Transoral thyroidectomy: advantages and limitations

In this opinion paper of the Journal of Endocrinological Investigation, leading experts in the field report on their current clinical experience with a novel approach for thyroid gland surgery, namely, "transoral thyroidectomy" (TOT). This feasible and novel surgical procedure does not require visible incisions and is, therefore, a truly scarless surgery. Patients meeting the following criteria can be considered as candidates for TOT: (a) an ultrasonographically (US) estimated thyroid diameter ≤10 cm; (b) US-estimated gland volume ≤45 mL; (c) nodule size ≤50 mm; (d) presence of a benign tumor such as a thyroid cyst or a single- or multi-nodular goiter; (e) Bethesda 3 and/or 4 category and (f) papillary microcarcinoma without the evidence of metastasis. The procedure is conducted via a three-port technique at the oral vestibule using a 10-mm port for the 30° endoscope and two additional 5-mm ports for the dissecting and coagulating instruments. TOT is performed using conventional endoscopic instruments and is probably the best scarless approach to the thyroid because of the short distance between the thyroid and the incisions placed intra-orally that do not result in any cutaneous scar and upon following the surgical planes. Experts in TOT organized a working group of general, endocrine, head and neck ENT surgeons and endocrinologist to develop the standards for practicing this emerging technique.

Recurrent laryngeal nerve injury in video-assisted thyroidectomy: lessons learned from neuromonitoring

INTRODUCTION

The objective of the study was to assess the mechanism of recurrent laryngeal nerve (RLN) injury during video-assisted thyroidectomy (VAT).

METHODS

The study examined 201 nerves at risk (NAR). VAT with laryngeal neuromonitoring (LNM) was outlined according to this scheme: (a) preparation of the operative space; (b) vagal nerve stimulation (V1); (c) ligature of the superior thyroid vessels; (d) visualization, stimulation (R1), and dissection of the RLN; (e) extraction of the lobe; (f) resection of the thyroid lobe; (g) final hemostasis; (h) verification of the electrical integrity of the RLN (V2, R2). The site, cause, and circumstance of nerve injury were elucidated with the application of LNM. Laryngeal nerve injuries were classified into type 1 injury (segmental) and 2 (diffuse).

RESULTS

Fourteen nerves (6.9 %) experienced loss of R2 and V2 signals. 80 percent of lesions occurred in the distal 1 cm of the course of the RLN. The incidence of type 1 and 2 injuries was 71 and 29 % respectively. The mechanisms of injury were traction (70 %) and thermal (30 %). Traction lesions were created during the extraction of the lobe from the mini-incision [point (e)]. Thermal injury occurred during energy-based device use in (f) and (g) circumstances.

CONCLUSIONS

RLN palsy still occurs with routine endoscopic identification of the nerve, even combined with LNM. LNM has the advantage of elucidating the mechanism of RLN injury. Traction and thermal RLN injuries are the most frequent lesions in VAT.