Introduction
Transoral endoscopic thyroid surgery via a vestibular approach is currently considered a feasible and safe surgical method (1). Transoral vestibular approach thyroid surgery has become the most common established remote access technique to avoid the traditional transcervical incision or any other cutaneous incision since its initial description (2). Nonetheless, in some patients with thyroid disease, born with short chins and mandibular retrusion, chin augmentation techniques have achieved improved outcomes with high patient satisfaction (3). If transoral endoscopic thyroid surgery via a vestibular approach is performed in these patients, chin augmentation genioplasty performed in same incision and same period prevents further trauma (1). As infection rates seem to be as low as in conventional open thyroid surgery, infection does not to be a specific problem of transoral thyroid surgery (4). However, the feasibility of transoral endoscopic thyroid surgery via a vestibular approach with chin augmentation genioplasty remains unclear and the safety of this approach should be established. To the best of our knowledge, there are no reports available in the literature to show the operation of transoral endoscopic thyroid surgery via a vestibular approach and chin augmentation genioplasty together. The main concerns for surgeons may be the insurgence of infection and implant displacement. To address these issues, the present study reports 3 cases in which these two surgical approaches were compared.
Results
Patient demographic and clinicopathologic details are listed in Table I. None of the patients developed major complications (e.g., postoperative bleeding, neck infection, chyle leakage, vocal cord paralysis or hypoparathyroidism). All patients developed transient skin numbness in the mandibular area and patient no.1 recovered within 4 months, patient no. 2 within 1 month and patient no. 3 within 2 months, which is similar to ordinary endoscopic transoral thyroid surgery (8). The longest follow-up period was 22 months (range, 2-22 months). The incisions in the oral cavity and breast healed well in all the patients according to the SCAR (Scar Cosmesis Assessment and Rating) scale (10).
There were no complications, such as infection or displacement of the implant. All patients were satisfied with the cosmetic outcomes (Fig. 2, Fig. 3 and Fig. 4). There was no evidence of local recurrence or distant metastases. The verbal response scale of cosmetic results in all three patients were 4 grade.
Discussion
In 2009, Wilhelm and Metzig (11) made the first known attempt at transoral endoscopic thyroid surgery in Germany. The surgery was performed via a sublingual approach combined with a vestibular approach. This approach presented several advantages compared with transoral thyroid surgery such as moving the incision site out of the visible cervical region to meet the higher cosmetic demands of patients, and it was further developed into a total vestibular approach (1). Transoral endoscopic thyroid surgery via the vestibular approach was appropriate for treating PTC without lateral lymph node metastasis, while for PTC with lateral lymph node metastasis, the ELNDBTOA was performed in the general surgery department of Zhongshan Hospital, Xiamen University (7). According to the present clinical observation, some patients suffered from thyroid cancer and microgenia simultaneously in ZhongShan Hospital, Xiamen University.
Facial aesthetics can affect a patient's appearance and self-esteem, and the chin is an important feature in the aesthetic perception of the face. A deficient chin may be short or shrink back, which is diagnosed as microgenia. Genioplasty is an efficient treatment option for the correction of chin deformities (12). Since transoral endoscopic thyroid surgery via the vestibular approach and chin augmentation genioplasty both involve the chin, it was hypothesized that it was possible to perform these two operations at the same time.
A wide variety of materials such as silastic (solid silicone), mersilene mesh (polyester fiber mesh), supramid (polymide nylon mesh), proplast (polytef), medpor (porous polyethylene) and Gore-Tex (polytetrafluoroethylene) in chin augmentation are currently available (13). These materials vary in density, ability to be sculpted, tissue reaction, resorption, migration, the incidence of infection, extrusion rate and ease of removal. Silastic augmentation genioplasty is a common procedure, with consistent aesthetic results in properly selected patients who have short chins and mandibular retrusion (13). Silastic augmentation genioplasty may be the best choice if there are any concerns regarding infection or potential future infection (13). It is also inexpensive and easily sculpted; therefore, it was selected for the present study.
Common complications of chin implantation include, in decreasing order of importance, asymmetry, malposition, infection, extrusion, mental nerve dysfunction and chin ptosis (14,15). A case series of 324 chin implants found an infection rate of 0.62%, while another case series of 125 consecutive patients reported no infections (16,17). It has been suggested that the infection rate may increase after the proposed combination surgery since transoral endoscopic thyroid surgery via a vestibular approach and the ELNDBTOA are long surgeries. Nonetheless, the present cases did not present with related complications. The absence of related complications might be due to the small number of cases considered in the present study and the short follow-up time. One drawback of a silastic chin prosthetic is the risk of resorption at the implant-bone interface (18). Porous polyethylene typically presents a higher risk of infection and was therefore not used in the present study (19). Perhaps another attractive alternative chin implant material may be developed in the future. Further investigation is needed to elucidate this new technique and assess the rates of infection and extrusion.
Despite the study being limited to these 3 selected patients with PTC and microgenia, the follow-up to the initial description of the new technique established the safety and efficacy of the procedure. This new combined technique needs to be further explored to confirm its feasibility and safety.