OBJECTIVE
The cultural desire to avoid cervical incisions has motivated surgeons to develop alternative approaches to thyroid surgery. The most common technique employs an axillary incision and subcutaneous tunneling for resection of the thyroid. This access is more challenging in the obese patient, limiting the patients who are candidates for minimally invasive thyroid surgery. Further, traditional rigid instruments are unable to gain sufficient triangulation through a single-incision in a subcutaneous space and may require multiple incisions or robotic assistance. The Direct Drive Endoscopic System (DDES, Boston Scientific, Natick, MA) platform combines a flexible endoscope with a pair of separately-controlled articulating instruments through a single, flexible, access system. We hypothesized that the DDES platform would permit single-incision minimally-invasive thyroid lobectomy without robotic assistance.
METHODS
One endocrine and two minimally invasive surgeons utilized the platform to perform a thyroid lobectomy on a cadaver. A single, 2.5 cm sub-xiphoid incision was used for access. The platform’s 55-cm flexible sheath was secured to the operating table rails and introduced into the subcutaneous space. A flexible pediatric endoscope was simultaneously introduced with two, interchangeable 4 mm instruments. The controls allow three degrees of translational freedom (surge, heave, and sway) and three degrees of rotational freedom (pitch, yaw, and roll). Blunt dissection and electro-cautery, were used to create the tunnel. The thyroid was dissected using a superior to inferior technique. The thyroid was dissected, maintaining the critical steps of traditional thyroid surgery, including close ligation of the vascular pedicles, preservation of parathyroid glands, and identification of the recurrent laryngeal nerve. A Veress needle introduced through the lateral neck provided additional retraction.
RESULTS
The total operating time was 2.5 hours. The subcutaneous tunnel using the sub-xyphoid approach was safe and accommodated the DDES well. Visualization was adequate. Graspers, scissors, and hook cautery were used to complete the lobectomy. Though the table-fixed system is adjustable, we found it easier to adjust the surgeon’s standing height rather than the system. The ergonomics, articulation and strength of the instrumentation was superior to previous flexible endoscopic systems used by our group.
CONCLUSIONS
Sub-xyphoid thyroidectomy is possible and avoids the difficulties inherent to a transaxillary approach while still avoiding cosmetically unappealing cervical scars. Developments in engineering and design continue to decrease the trade-off traditionally required between flexibility and strength of flexible endoscopic platforms . Continued technological refinement will only expand the therapeutic possibilities of flexible endoscopy while minimizing the physical insult to and maximizing aesthetics for patients.