Introduction

Diseases of the thyroid gland have been well recognized for more than 3,500 years. Goiterous thyroid enlargement, causing obstructive symptoms, was the predominant reason for surgical intervention. Early thyroidectomy procedures were accompanied by a strikingly high mortality rate, reaching 41% in 1850. Theodor Kocher′s contribution to thyroid surgery, with later refinement of his surgical technique by William Halsted, Charles Mayo, and George Crile, made thyroidectomy much safer. Since then, conventional thyroidectomy has remained largely unchanged and today is associated with very low morbidity.

The indication for surgery, however, has changed from goiter to nodular disease. Over the twentieth century, imaging and fine-needle aspiration biopsies led to earlier detection of subclinical nodules. As surgeons transitioned to operate on smaller glands, they began to push for less significant neck incisions in an effort to preserve the patient′s cervical form and appearance. Endoscopic and minimally invasive surgery evolved first in the field of parathyroid surgery. ¹ Difficulties with intraoperative adenoma localization and damage to surrounding structures had long hindered the use of targeted, minimally invasive approaches for parathyroidectomy. However, more recent significant improvements in the accuracy and reliability of preoperative localization studies have facilitated further evolution in surgical management, enabling a more targeted minimally invasive surgical approach. Increased understanding of the endoscopic view of the cervical anatomy, as well as improvements in surgical endoscopic instruments, contributed to the growth of minimally invasive thyroid and parathyroid surgery. Initial methods included the use of endoscopes with gas insufflation to overcome the limited visualization provided by these smaller incisions. ¹ , ² They were poorly received, however, because subplatysmal insufflation created a noncontained cavity within the neck. Also, subcutaneous emphysema, systemic absorption of carbon dioxide, and severe tachycardia were feared complications that were reported in the literature.

Conversely, in Southeast Asia, due to the prevalence of aesthetically undesirable scarring, and the resulting social stigmatization of young females with a visible scar, the remote endoscopic technique was implemented, refined, and later enhanced with advancements in robotic technology. ³ , ⁴ , ⁵ Remote access approaches using surgical ports placed in several locations outside the neck, including the anterior chest wall, subclavicular region, and axillary region, have been described lately, all with success. ³ , ⁴ , ⁵ , ⁶ , ⁷ , ⁸ , ⁹ , ¹⁰ , ¹¹ , ¹² , ¹³ These approaches were intended to avoid cervical scarring, but also to result in less pain with a faster return to functional activities, as documented in the Korean experience. ¹⁴ , ¹⁵ Surgeons have found that the ability to control a magnifying three-dimensional high-definition camera system with a stable platform and multiarticulated, tremor-free endoscopic arms through a single console restores some of the fundamentals that were lost in the transition to endoscopic surgery. ³ , ⁵ , ⁶ This is particularly advantageous in the restricted workspace afforded in this region of the body and provides access to perform bilateral central and modified radical neck dissection in addition to total thyroidectomy. ¹⁵ , ¹⁶ , ¹⁷ , ¹⁸

This chapter will provide the reader with an overview of our experience with the robotic-assisted transaxillary approach with the modifications required in the Western population.

Indication and Patient Selection

Despite the beautiful anatomical nature of thyroid and parathyroid surgery, the surgeon must be aware that many young female patients will mainly focus on incision length, location, design, and healing in the assessment of the overall quality of the surgery, as well as complications. Therefore, guiding principles that can serve as a framework for the safe implementations of these emerging technologies in thyroid surgery should be considered to avoid any unnecessary harm ( Table 7.1, Table 7.2 ). ¹⁹ , ²⁰ Nonetheless, ideal patient selection criteria are not well established. The best candidates for this approach are small or average-sized (body mass index < 30 kg/m²) young patients who have concerns about neck scarring or have a history of keloid or hypertrophic scar formation. Our group has reported a safe and feasible expansion of these selection criteria after appropriate experience with an appropriately selected group of patients. In our experience with the transaxillary approach, 60% of our patients were overweight or obese, and the average thyroid nodule size was 2.4 cm. ⁶ We and others have also reported the feasibility of this approach in patients with well-differentiated thyroid cancer and cases of Graves’ disease, as well as central and lateral neck dissection. ¹⁴ , ¹⁵ , ¹⁶ , ¹⁷ , ¹⁸ , ²¹ , ²² Still, we believe that keeping the selection criteria conservative is vital for the safety and efficacy of robotic-assisted thyroid procedures, especially during the beginning of the surgeon′s learning curve. This approach is usually deferred in patients with a previous history of neck surgery or irradiation of the neck. Patients should also be screened for contraindications that affect patient positioning during this procedure, such as rotator cuff pathology, shoulder/neck mobility problems, cervical spine disease, or previous neck, chest, or axillary surgery. The transaxillary approach provides access to perform total thyroidectomy or central or lateral neck dissection, whereas only unilateral thyroid lobectomy can be performed via the retroauricular approach.

Special Equipment and Room Setup

The robotic-assisted approach facilitates endoscopic neck surgery while maintaining a three-instrument approach. The surgeon can retract, view target surgical anatomy, and still have two arms to operate, while maintaining traction and countertraction.

Robotic wristed instruments permit the surgeon to reduce physiological tremors and increase the surgeon′s operative free dexterity of movement. Three robotic instruments—Maryland dissector, ProGrasp forceps (Intuitive Surgical), and Harmonic curved shears (Ethicon)—and a dual-channel camera are needed. By placing the camera through the axillary incision and using an endoscope with 30° down-looking orientation, principles from the conventional cervical approach can be applied safely to this endoscopic technique ( Table 7.3 ). During development of the working space, electrocautery, a vascular DeBakey forceps and various retractors (Army-Navy, right-angled, and lighted breast retractors) are used for subcutaneous flap dissection and elevation.

It is important for the surgeon to determine the best way to organize the operating room prior to the procedure. The operating table is positioned where the anesthesiologist should have an access to the patient′s airway. We highly advocate the use of a laryngeal nerve monitor. The patient cart is covered with sterile drapes and positioned on the contralateral side of the operating table. The patient cart is initially kept away from the operating table during the development of the working space to allow space for the surgical assistant to work across the table and retract the thyroid.