A dangerous MIS-correct proposal

Abstract

We have read with interest the article entitled ‘‘Transoral thyroid and parathyroid surgery’’ [1]. This article describes a new minimally invasive surgical approach to the thyroid and parathyroid glands. It appears that the purpose of the study was to (1) demonstrate the feasibility of a transluminal endoscopic approach to thyroid and parathyroid surgery; (2) describe a new minimally invasive technique which has improved cosmetic results; and (3) promote a minimally invasive technique to thyroid surgery that offers minimal disruption to surrounding tissues and structures. The article focused on a proof of concept through surgery on porcine and human cadavers and also on live porcine subjects. It sites the embryological and anatomical similarities between pigs and humans when justifying their use of porcine subjects. The results in these subjects appears to be promising. However, the article failed to address a number of important questions regarding the feasibility of translating this impressive work into a procedure that can be widely adopted by endocrine surgeons. If we understand the article correctly, the technique can be described as minimally invasive surgery (MIS) because of the use of a potential anatomical space previously described by Newell [2]. However, as with other MIS techniques used on the thyroid, the size of the incision is limited [3]. In this case, it appears that the incision is limited to approximately 10 mm in length, somewhat smaller than current MIS methods. As such, this will limit the size of any thyroidectomy to approximately 20 ml in volume, consequently reducing the range of pathologies on which the technique can be employed. This may be particularly significant for tumour resection where the actual tumour extends beyond the capsule of the thyroid gland. Another problem with this technique is the potential for infection. The oral cavity and pharynx are unclean spaces. They cannot be cleaned and therefore pose a significant infection risk. It is likely that due to this infection risk antibiotic cover will be required in all cases, something not routinely required in current minimally invasive thyroid surgery. A further problem, common to most endoscopic procedures, is the necessity to clean the camera of debris and fluids to ensure an adequate view of the surgical site. In the case of a transluminal approach, there is the risk of trauma to surrounding tissues and structures due to repeated insertion and removal of the instrument for cleaning [4, 5]. The article also suggests the possibility of using CO2 gas as a means of creating a surgical space. We acknowledge that this was not actually employed by the authors and we would caution against its use due to the potential risk creating a pneumomediastinum. Although we have highlighted some areas for consideration by the authors, we would like to congratulate the team on their endeavours and look forward to seeing how their work is developed.