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Mammana et al. Mini-invasive Surg 2020;4:37 I http://dx.doi.org/10.20517/2574-1225.2020.24 Page 3 of 7

movement of the hands and fingers into precise, identical, and real-time movements of surgical instruments
inside the patient’s chest.

Robotic thymectomy might be considered an evolution of the VATS approach. In fact, the high-resolution
three-dimensional view of the operating field, attenuation of hand tremor and articulation of the robotic
arms represent clear advantages of RATS over VATS thymectomy, especially in difficult to reach or
narrow anatomical regions, such as the mediastinum. In the few studies where the RATS approach was
compared with VATS, the investigators pointed out that the former approach is feasible and safe, and that
[13]
it presents surgical advantages over the latter [13,14] . Moreover, Rückert et al. noted an improved outcome
in myasthenic patients operated on by a robotic approach compared with those operated by VATS, which
could have been due to the superior mediastinal dissection achieved with RATS. On the other hand,
RATS thymectomy has some disadvantages. First, it is more expensive than VATS thymectomy, with
most of the expense being due to the acquisition of the robotic system, its annual maintenance and the
disposable materials. Second, there is a lack of tactile feedback that could increase the risk of damaging
delicate anatomical structures. However, this seems to be widely compensated by the superior three-
dimensional view provided by the robotic console and the improved dexterity of robotic arms. Lastly, the
operating surgeon is unscrubbed and placed away from the patient; therefore, in case of intraoperative
complications requiring emergency conversion to sternotomy, another surgeon needs to stay sterile next to
the patient [15-17] .

PATIENT SELECTION AND PREOPERATIVE PREPARATION
On the basis of current evidence, thymectomy is indicated for patients affected by generalized MG (grades
II to IV, according to MGFA classification) and who are AChR antibody positive. No age limit exists;
however, because it is an invasive procedure, the benefits of thymectomy have to be weighed against the
risks of surgery, particularly in elderly patients. The chance of a complete remission of the disease decreases
with age and with time from the onset of symptoms; therefore, there is general consensus that thymectomy
[6]
should be offered early in the course of the disease of patients affected by MG . Thymectomy may be
offered also to MG patients without detectable levels of AChR antibodies; however, current guidelines do
[18]
not support thymectomy in patients with MuSK, LRP4, or agrin antibodies . Because of the long delay
in onset of effect, thymectomy for MG is an elective operation; therefore, it should be proposed only to
patients who are stable and deemed safe to undergo a procedure where postoperative pain and mechanical
factors can limit respiratory function. In patients with thymomatous MG, surgery is indicated in any case
to remove the tumor, regardless of the expected improvement in MG symptoms.

Preoperative workup includes contrast-enhanced computed tomography (CT), pulmonary function tests
and blood gas analysis. The neurologist should evaluate all symptomatic patients to determine the need for
intravenous immunoglobulin therapy or plasmapheresis in the immediate preoperative period.

SURGICAL TECHNIQUE
The surgical steps of robotic thymectomy are well described and there are only slight modifications in them
[19]
across centers, as described elsewhere . Both a right-sided and a left-sided approach are feasible, and,
while every surgeon has a preferred approach (at our center this is the left-sided one), the procedure should
be tailored on the patient’s anatomy, and there should be no hesitation to add a contralateral incision if
required. The main goal, in fact, should be to achieve a radical en-bloc resection of all thymic tissue, from
one phrenic nerve to another, and from the inferior poles of thyroid gland to the diaphragm. Advantages of
the left-sided approach include a usually larger distribution of the thymic gland and of the mediastinal fat
to the left side and around the left phrenic nerve, accessibility to the aortopulmonary window, and a better
visualization of the contralateral phrenic nerve, which is protected in its superior portion by the superior