Page 612 - Read Online
P. 612

Page 6 of 16                                     De Iaco et al. Mini-invasive Surg 2020;4:63  I  http://dx.doi.org/10.20517/2574-1225.2020.37

               During the years, to surpass these limits, some modified and combined approaches have been described.
                             [34]
               Ampollini et al. , for example, described a modified video-assisted transcervical approach, which, using
               the instruments developed for the minimally invasive thyroidectomy, enable the surgeon to perform the
               thymectomy without neck hyperextension or permanent sternum elevation, which are mainly responsible
                                          [35]
               for postoperative pain. Yu et al. , instead, proposed a combined transcervical and unilateral-thoracoscopic
               thymectomy approach to reach the residual thymic tissue, which might have been left behind in the
               superior horns or in the upper poles into the base of the neck.

               SUBXIPHOID THYMECTOMY
                                                                       [36]
                                                                                                   [37]
               The subxiphoid approach was introduced in 1999 by Kido et al. , paving the way for Hsu et al. , who
               first performed subxiphoid video-assisted thoracoscopic extended thymectomy in 2002. Since then, the
               subxiphoid approach has been used successfully and many techniques have been described according to
               the incision design: the uniportal or dual-port subxiphoid approach [38-40] , the subxiphoid and subcostal arch
               approach, subxiphoid robotic thymectomy [41,42] , and a combination of the transthoracic and subxiphoid
               approaches .
                         [43]
               Each technique should be chosen on the basis of the personal preference of the surgeon along with
                                                                                           [44]
               his experience and of the single case to treat, according to its anatomical peculiarities . Although the
               uniportal approach seems to be the most minimally invasive approach in existence, it is not an easy
               technique to learn because of the reduced instrument maneuverability; however, in skilled hands, this limit
               could be overcome with specially modified instruments and angled thoracoscopes [45,46] . Since the increase
               in the number of the ports can help obtain a multidirectional view, increasing the safety of the procedure,
               single-port thymectomy should be started following the training of two- or three-port thymectomy .
                                                                                                       [47]
               The subxiphoid robotic approach is the one with the best maneuverability: the left and right robot arms
               are inserted in the 6th intercostal space. and the entire target/thymus lies between the left and right arms,
                                                        [42]
               thereby enabling maximum robot performances .

               The advantages of the subxiphoid approach are numerous; since the camera is inserted into a subxiphoid
               incision in the midline of the body, the surgical field is comparable to that in a median sternotomy. This
               helps identify the location of the bilateral phrenic nerves and confirm the location of the superior pole of
               the thymus while offering a good visualization in the neck area and a safe dissection of thymic veins .
                                                                                                       [42]
               Other advantages include minimal postoperative pain with no occurrence of intercostal neuropathy
               since intercostal spaces are not traversed and cosmetic outcomes are excellent [43,44,48] . In contrast, when
               comparing the subxiphoid view to the lateral one in the traditional VATS, it becomes difficult to identify the
               contralateral phrenic nerve, and there is also the risk of intercostal nerve injury, resulting in postoperative
                                                [43]
               chronic incision pain [43,49] . Zhang et al.  recently conducted a retrospective analysis comparing 98 patients
               who underwent a VATS thymectomy through the subxiphoid and subcostal arch approach or the lateral
               intercostal one. They found statistically significative differences in the length of hospital stay, postoperative
               pain, and cosmetic satisfaction in favor of the subxiphoid approach.


               To deal with larger thymomas and difficult selected cases, some modified approaches have been described.
                                             [16]
               In their experience, Zieliński et al.  proposed a “maximal” transcervical subxiphoid video-thoracoscopic
               thymectomy, in which, at the same time, two teams work from above and below the sternum to dissect
               the thymus while using a double sternal elevator. This technique has the advantage to be more extensive
               in regard to the removal of fatty tissue from the aorta-caval groove and fatty tissue anterior to the trachea,
               almost reaching the level of tracheal bifurcation. On the other hand, even if the two-team approach helps
               to reduce the operative time, it is a far more invasive technique than unilateral VATS affected by more
               complications than traditional VATS.
   607   608   609   610   611   612   613   614   615   616   617