After skin preparation, the surgeon marks the midline, the major anatomical landmarks (including the thyroid and cricoid cartilage, sternocleidomastoid muscles, clavicles, and suprasternal notch), and finally the different proposed incisions (Fig. 8.2). A 12-mm incision is marked in the axilla ipsilateral to the side of the thyroid pathology and a 5-mm incision is placed in the contralateral axilla. Symmetrical, 5-mm incisions are placed in the superomedial margins of the areolas.

A 1:200,000 epinephrine solution is then injected in the working area deep to the platysma muscle in the neck and the subcutaneous tissues on the anterior chest (Fig. 8.3a). In the neck area, a “pinch and raise” maneuver of the skin helps the injection of saline distribute into the subplatysmal space (Fig. 8.3b). This “hydrodissection” technique results in the formation of a saline pocket in the subplatysmal space, which can decrease bleeding in the flaps and makes the dissection easier.

After incisions are made in both axillae, blunt dissection is performed with a straight mosquito clamp and a vascular tunneler to elevate the flaps. The 12-mm incision is used to extract the specimen later in the case. After blunt dissection, the ports are inserted through the incisions. The working space is maintained with CO₂ gas insufflation at the pressure of 5–6 mmHg. Visualization is achieved with a 30° endoscope.

The next phase of the surgery requires sharp dissection which is achieved using a Harmonic device. The dissection should start in the infraclavicular area (Fig. 8.4). When this dissection is completed, the two 5-mm incisions in the superomedial margins of the areola of the breasts are made. The myocutaneous flap is then extended more cephalad, up to the thyroid cartilage.

With the endoscope, the strap muscles and midline raphe can be well visualized. The midline is then divided with electrocautery from the thyroid cartilage to the suprasternal notch, exposing the isthmus of the thyroid gland (Fig. 8.5a, b). The thyroid isthmus is then divided in the midline using the Harmonic device. Prior to isthmectomy, the absence of isthmus lesions should be verified.

While the thyroid gland is retracted medially with an endo-clinch, the strap muscles should be retracted laterally with the forceps. Dissection is carried down to the deep aspect of the gland to expose its lateral surface. With a snake retractor drawing the strap muscles farther laterally (Fig. 8.6), additional lateral dissection can be accomplished. In order to expose the lateral part of the thyroid gland for dissection, the gland can be medially retracted with a “switching motion” of the instruments (Fig. 8.7). The middle thyroid vein is identified and divided during this stage of the procedure.

Before the inferior thyroid artery enters the thyroid glands, it passes directly under or over the recurrent laryngeal nerve. The inferior thyroid artery can thus be used as a guide to finding the recurrent laryngeal nerve. If the nerve cannot be exposed immediately, further dissection is needed of the loose fibrous tissue at the point of the artery near the tracheal esophageal groove. After the nerve is identified, it is traced from the area of the tubercle of Zuckerkandl to the ligament of Berry.

The inferior parathyroid gland can often be identified in this area. It is generally located near the branching point of the inferior thyroid artery. The gland is preserved by dissecting the gland in an inferior direction, maintaining the vascular pedicle. If the parathyroid gland cannot be preserved, reimplantation should be performed. The pectoralis major muscle serves as excellent option for reimplantation in BABA thyroidectomy.

Attention is then turned to the superior pole of the thyroid gland. Using Maryland forceps to retract the strap muscles laterally, the upper pole of the gland is dissected with the harmonic device. It is important to preserve the fascia of the cricothyroid muscles, because the external branch of the superior laryngeal nerve is closely associated with it. The terminal branches of the superior thyroidal artery and vein are identified and carefully ligated with the harmonic shears. The branch that serves as the vascular supply to the superior parathyroid gland should be preserved (Fig. 8.8).

After dissecting the thyroid gland away from the trachea, the specimen is wrapped with a plastic bag and removed via the 12-mm axillary port. The specimen is inspected with care to identify any excised parathyroid gland. After meticulous hemostasis is achieved with electrocautery, the right and left strap muscles are reapproximated in the midline. One Jackson-Pratt (JP) drain is placed into the thyroid pocket via an axillary port. The skin of the breasts and axillae are sutured with buried stitches with absorbable sutures.