Invisible scar endoscopic thyroidectomy by the dorsal approach: experimental development of a new technique with human cadavers

Abstract
Background  A unilateral gasless single-surgeon videoendoscopic thyroidectomy procedure using a dorsal cephalic approach from the scalp
with the option for a bilateral approach was developed with human cadavers and a porcine model for access training. The final
preclinical trials and the first three clinical cases are described in detail.

Methods  Preclinical evaluation and training for the procedure were conducted with fresh human cadavers. The procedure was defined
precisely by a sequence of nodal points initiating surgical steps. A quality score was developed by issuing each important
anatomic structure a specific organ value and a factor for positive identification, inability to identify a given anatomic
structure, spare it (meaning omit causing a lesion) or injure the structure. The quality of each operation was expressed as
a single number or quality score value, calculated by summing the points achieved for the individual anatomic structures.
The results of the procedures were controlled by prospective video documentation and autopsy. After conclusion of the preclinical
training, the operation was performed for patients. The reported patients are part of a feasibility study approved by the
institutional review board of the University of Munich.

Results  Nodal points were helpful in preparation for the operation by mental training. During the procedure, they helped to guide
the preparation in the neck, where the working space must first be created on the way to the target organ. The surgical quality
score improved over the first three cases and reached the maximum score, which was reproducible every time after that. It
showed that the dorsal approach from the scalp to the thyroid gland is easily achievable without complications. The technical
challenge is exposure of the recurrent laryngeal nerve (RLN) and the parathyroid glands. There was no difference between the
results achieved by the resident and the senior surgeon. Preclinical training was good preparation for hemithyroidectomy in
patients. All cases could be managed without postoperative hemorrhage or impairment of the parathyroid or the RLN.

Conclusions  Videoendoscopic thyroidectomy by the dorsal approach is feasible in both human cadavers and patients. It leaves no visible scars. Nodal points are helpful for executing a new operation. The surgical quality score is a complex
and objective measure of ability to deal with the procedure. Further clinical studies are required for evaluation of this
new procedure.

Content Type Journal ArticleCategory ReviewDOI 10.1007/s00464-008-9761-yAuthors
Hans Martin Schardey, Agatharied Academic Teaching Hospital of the Ludwig-Maximilians-University Munich Department of Visceral Surgery St. Agathastr. 1 83734 Hausham/Oberbayern GermanyStefan Schopf, Agatharied Academic Teaching Hospital of the Ludwig-Maximilians-University Munich Department of Visceral Surgery St. Agathastr. 1 83734 Hausham/Oberbayern GermanyMichael Kammal, Institute of Forensic Medicine University Hospital Hamburg-Eppendorf Hamburg GermanyMirco Barone, Agatharied Academic Teaching Hospital of the Ludwig-Maximilians-University Munich Department of Visceral Surgery St. Agathastr. 1 83734 Hausham/Oberbayern GermanyWolfgang Rudert, Agatharied Academic Teaching Hospital of the Ludwig-Maximilians-University Munich Department of Visceral Surgery St. Agathastr. 1 83734 Hausham/Oberbayern GermanyThomas Hernandez-Richter, Practice of Plastic Surgery Munich GermanyStefan Pörtl, Practice of Endocrinology Miesbach Germany

Journal Surgical EndoscopyOnline ISSN 1432-2218Print ISSN 0930-2794 (Source: Surgical Endoscopy)