Modifications of Miccoli minimally invasive thyroidectomy for the low-volume surgeon

Morbidity from minimally invasive video-assisted thyroidectomy: a general review

Minimally invasive video-assisted thyroidectomy (MIVAT) is known and used worldwide, it combines the advantages associated with endoscopic magnification with those due with traditional surgery. In selected patients, it should be considered a safe and valid alternative. Indeed, a lot of comparative studies have demonstrated the advantages of MIVAT in terms of low rate of complications, reduced postoperative pain, improved cosmetic results and higher patient satisfaction over traditional surgery. Anyway, for obtaining the best results, with similar or even less complication rate than traditional surgery, surgeons should be well trained, acquired confidence with a smaller surgical incision and with the use of endoscopic instruments.

Minimally invasive video-assisted thyroidectomy: reflections after more than 2400 cases performed

BACKGROUND

The minimally invasive video-assisted approach was developed for primary hyperparathyroidism in 1997 and the year after for thyroid disease. Since then, the technique has been adopted worldwide, and indications moved from the initial benign disease to low-risk and intermediate-risk carcinoma, demonstrating a level of oncologic radicality comparable to the conventional open approach when inclusion criteria are strictly respected.

METHODS

Between 1998 and 2014, 2412 minimally invasive video-assisted thyroidectomies (MIVAT) were performed in our department. The indication for surgery in 825 patients (34.3 %) was a malignant tumor, in particular, a papillary carcinoma in 800 patients. Among them, 528 patients operated on between 2000 and 2009 had a mean complete follow-up of 7.5 (standard deviation, 2.3) years.

RESULTS

A total thyroidectomy was performed in 1788 patients (74.1 %) and a hemithyroidectomy in 564 (23.4 %). Also performed was central compartment lymphadenectomy in 31 patients (1.3 %) and parathyroidectomy for the presence of a solitary parathyroid adenoma in 29 (1.2 %). Mean duration of the procedure was 41 (standard deviation, 14) minutes. After a mean follow-up of 7. 5 years, 528 patients who underwent MIVAT for low-risk or intermediate-risk papillary carcinoma presented a cure rate of 85 % (undetectable thyroglobulin), comparable with the 80 % rate reported in patients who had undergone open thyroidectomy during the same period.

CONCLUSIONS

After a long experience and a considerable number of procedures performed in a single center, MIVAT is confirmed as a safe operation, with a complication rate comparable with open thyroidectomy. MIVAT offers a cure rate for the treatment of low-risk and intermediate-risk malignancies that is comparable with an open procedure when inclusion criteria are strictly respected.

Minimally invasive compared with conventional thyroidectomy for nodular goitre

Since minimally invasive thyroidectomy was introduced in 1997, different surgical approaches to the thyroid have been described: the minimal neck incision and the anterior chest, areolar breast or axillary access. Whereas conventional open thyroidectomy is suitable for any thyroid disease, minimal neck incision thyroidectomy or extracervical scarless neck thyroidectomy are limited to small-volume disease. In 11 prospective randomized studies and six systematic reviews, minimally invasive video-assisted thyroidectomy via a central or lateral neck approach afforded better cosmesis in the first 3 months than conventional open thyroidectomy, with less postoperative pain for the first 48 h. Surgical morbidity did not differ in these limited studies. No head-to-head comparison is available for extracervical scarless neck thyroidectomy and conventional open thyroidectomy. Extracervical scarless neck thyroidectomy caused more postoperative pain and gave rise to complications not seen with minimal neck incision thyroidectomy or conventional open thyroidectomy. In the absence of evidence to the contrary, conventional open thyroidectomy continues to remain the gold standard for any nodular goitre.

Contemporary surgical techniques

Recent technologic advances have engendered alternative and innovative approaches to thyroid surgery aimed at reducing cosmetic sequelae. Minimally invasive techniques via small anterior cervical incisions hidden in natural skin creases and remote access approaches that eliminate anterior neck incisions entirely have emerged as viable options for patients who regard cosmesis as a priority. The safe application of these techniques to both benign and malignant thyroid disease has been evaluated.

Alternative approaches to the thyroid gland

Advances in surgical technology and patient-driven demands have fueled exploration into methods to improve cosmetic outcomes in thyroid surgery. This exploration has produced 2 fundamentally different pathways for reducing the visible thyroidectomy scar. Minimally invasive anterior cervical approaches use small incisions hidden in natural skin creases and reduce the overall extent of dissection required to remove the thyroid. Remote access approaches remove the incision from the anterior neck completely but require more extensive dissection to access the thyroid compartment.

Factors influencing the length of the incision and the operating time for total thyroidectomy

BACKGROUND

The incision used for thyroid surgery has become shorter over time, from the classical 10 cm long Kocher incision to the shortest 15 mm access achieved with Minimally Invasive Video-Assisted Thyroidectomy. This rather large interval encompasses many different possible technical choices, even if we just consider open surgery.The aim of the study was to assess the correlation between incision length and operation duration with a set of biometric and clinical factors and establish a rationale for the decision on the length of incision in open surgery.

METHODS

Ninety-seven consecutive patients scheduled for total thyroidectomy were prospectively evaluated. All operations were performed by the same team and the surgeon decided the length of the incision according to his personal judgement. Patients who had previously undergone neck surgery were excluded.

RESULTS

The length of the incision was strongly correlated with gender, thyroid volume, neck circumference and clinical diagnosis and weakly correlated with the body mass index. Operation duration was only weakly correlated with gender and neck circumference. Multiple linear regression revealed that the set of factors assessed explained almost 60 % of the variance in incision length but only 20 % of the variance in operation duration. When patients were classified according to the distribution of their thyroid volume, cases within one standard deviation of the mean did not show a significant difference in terms of operation duration with incisions of various lengths.

CONCLUSIONS

Although thyroid volume was a major factor in driving the decision with respect to the length of the incision, our study shows that it had only minor effect on the duration of the operation. Many more open thyroidectomies could therefore be safely performed with shorter incisions, especially in women. Duration of the operation is probably more closely linked to the inherent technical difficulty of each case.