Incisions in Thyroid and Parathyroid Surgery

Introduction

Among endocrine surgeries, thyroidectomy remains a demanding procedure because of the specific patient population, the decreasing surgical morbidity, and increasing patient expectations. Patients now seek safe surgery with preservation of the laryngeal nerves and parathyroid glands, but increasingly, they also express interest in a better cosmetic outcome. Thyroid surgical diseases disproportionately affect females more than males and younger individuals more than the elderly. This unequal representation has prompted research to develop more cosmetically favorable incisions. The proliferation of so-called scarless in the neck or remote-access approaches justifies the need for a separate chapter devoted to these innovative techniques (see Chapter 32 , Robotic and Extra Cervical Approaches to the Thyroid and Parathyroid Glands). Therefore this current chapter will focus on incisions within the visible area of the cervical neck. These incisions will be seen by the public, so the specific characteristics have now been more precisely defined for surgeons than in the past. Length, width, location in the neck, pigmentation, and vascularization are the principal determinants of a scar appearance. Recent evidence demonstrates that patients of every age, gender, and race prefer a shorter and thinner thyroidectomy scar.

This chapter presents historical discussions followed by a series of important guiding principles that serve as fundamental reference points during thyroid and parathyroid surgery incisional design. Specific procedural considerations are described, and then a concise enumeration of proposed best practices is offered.

Historical Perspectives

Historical Perspectives

Although Theodor Billroth was the first surgeon to perform thyroidectomy in a systematic fashion, Theodor Kocher was the first surgeon to pursue a safe and reproducible thyroidectomy. Kocher is quoted as saying that the thyroidectomy incision should be “as big as necessary, as small as possible,” which certifies him as the first minimally invasive thyroid surgeon. He is also recognized as the original cosmetic thyroid surgeon. Starting with the vertical incision ( Figure 40.1, A ; applying the concept that it is a vertical operation), he eventually modified it to the horizontal, more cosmetically oriented incision that now bears his name ( Figure 40.1, B and C ).

Because much of the earlier thyroid surgery was done for malignancy, descriptions emerged regarding the appropriate way to accomplish a thyroidectomy combined with a neck dissection. Popular incisions included the Lahey incision ( Figure 40.2, A ); the MacFee incision ( Figure 40.2, B ); and eventually, a hockey-stick type of incision ( Figure 40.2, C ). This last approach emerged after recognition of the dangers of trifurcated incisions in which the tips of the trifurcation were prone to ischemia and devitalization, which sometimes put the great vessels of the neck at risk. As the radical operations of the 1960s and 1970s gave way to the more selective operations of the 1980s and 1990s, neck incisions for thyroid and neck dissection also evolved.

General Principles

Several important principles merit consideration when planning a thyroidectomy or parathyroidectomy, and these transcend the specific procedure that is anticipated.

Location

Perhaps the most important element in optimizing access while maintaining good cosmesis is choosing the proper location for an incision. The fundamental and critical concept of using a skin crease and relaxed skin tension lines persists. It is nearly always preferable to identify and use a preexisting skin crease (if present), for this will result in the most optimally camouflaged scar. One must be cautious that normal creases may (especially in the more lateral portion of the neck) become asymmetric and even V-like in nature, rather than the more symmetric rounded creases of the lower central neck. For standard-length incisions, a good alternate choice, if a normal symmetric crease is unavailable, is a line parallel to a normal skin crease. All existing creases can be mapped to configure an incisional line parallel to a regional crease. The best way to identify the proper crease and overall location is with the patient sitting upright in the preoperative holding area rather than waiting until the patient is lying supine on an operating table ( Figure 40.7 ). This previously identified principle is critically important, and it has emerged as a standard contemporary practice. Deploying the incision in a predetermined skin crease while the patient is in the upright position leads to the most predictable and consistent final scar location. It is in this position that patients will be in public situations, such as dinner parties and cocktail receptions, and it is in this position that the suprasternal notch (and the depression created by the medial heads of the sternocleidomastoid muscle) can best be seen. In this way, the incision can be planned with the patient’s input and awareness. New evidence exists that the anterior cervical skin shifts significantly from the upright position to the final surgical position when the patient is supine with a gentle neck extension. Variation in the cranio-caudal incision location can lead to a scar either in an unfavorable vertical location that is difficult to conceal or to a scar in an area with a high risk of hypertrophic healing. The standard incision is best placed just above the suprasternal notch. Standard incisions placed too low—spanning this indented suprasternal notch region—may appear asymmetric, and they tend to be hypertrophic in their midsegment, unlike incisions placed higher in a more uniform, cylindrical region of the neck. Minimally invasive incisions might be placed in the hollow between the medial heads of the sternocleidomastoid muscle. Consideration also should be given to breast size, especially in younger women, as over time the incision will be pulled downward if the breasts are large and pendulous. This information may influence the choice of the vertical height of the incision.

The length of the incision will vary, depending on the circumference of the neck and the size of the gland or nodule although it should be noted that virtually always the benign gland or nodule can be bigger than the incision itself. These structures are compressible, and they can be manipulated through an incision smaller than the gland. In any case, the incision should be parallel to relaxed skin tension lines, following classic cosmetic principles.