On the left paratracheal nodal station, it is important to identify the left recurrent laryngeal nerve to prevent its injury. (Fig. 27.5) Once this is done, the left inferior paratracheal lymph nodes are either biopsied or removed one by one (not en bloc as in the subcarinal and right inferior paratracheal nodal stations). Coagulation should be restricted to the minimum necessary; a warm wet gauze is usually enough to control bleeding from the nodes or the fatty tissue. As on the right side, the procedure can be completed with the exploration of the left hilar nodes, those caudal to the upper rim of the left pulmonary artery.

Once the dissection is fnished, the gauzes are removed and a fnal inspection is performed to check for bleeding. Drainage is not needed and the incision is closed as for mediastinoscopy.

Transcervical Extended Mediastinal Lymphadenectomy

In comparison with VAMLA, transcervical extended mediastinal lymphadenectomy (TEMLA) is a more extensive procedure. The objective of TEMLA is to remove all the mediastinal nodes from the cervical station to the para-­ oesophageal station. A cervical incision slightly longer than that for mediastinoscopy is performed, and the sternum is elevated with a hook fxed to a metal frame mounted on the operating table. The procedure is almost exclusively performed in an open fashion, but a two-bladed mediastinoscope is used to dissect the subcarinal and the para-oesophageal lymph nodes, and a videothoracoscope is inserted to have a better vision at the time of dissection of the subaortic space [12].

Evidence-Based Review

Conventional Mediastinoscopy

Versus Video-Mediastinoscopy

There are evident advantages of video-­ mediastinoscopy over conventional mediastinoscopy. The view of the operative feld is much larger and can be seen simultaneously by all personnel in the operating theatre. The whole

procedure or parts of it can be recorded for future use in clinical sessions, medical meetings and educational materials. However, because there are no prospective randomized trials comparing both procedures, there is no clear evidence indicating that video-mediastinosocopy is safer or more effective than conventional mediastinoscopy. Video-mediastinoscopy seems to be a more thorough exploration, because of an increased number of biopsied lymph nodes and explored lymph node stations compared with conventional mediastinoscopy, as well as a better tool for training [59].

Staging Values of the Diferent

Techniques

A review of 26 reports published between 1983 and 2011, including a total of 9267 patients who had undergone conventional mediastinoscopy, showed a median sensitivity of 0.78 and a median negative predictive value of 0.91. An additional series of 995 patients who had undergone video-­ assisted mediastinoscopy and were reported in seven papers published from 2003 to 2011 showed a median sensitivity of 0.89 and a median negative predictive value of 0.92. By convention, specifcity and positive predictive value of mediastinoscopy is 1, although positive results are not confrmed by other tests [18].

The combined analyses of 456 patients who underwent extended cervical mediastinoscopy reported in fve articles published between 1987 and 2012 revealed a median sensitivity of 0.71 and a median negative predictive value of 0.91 [18].

The initial reports from the two groups who developed VAMLA in 2002 and 2003, describing their results with 40 and 25 patients, respectively, showed sensitivities, negative predictive values and diagnostic accuracies of 1 [10, 11] An updated publication from one of the groups, with 144 patients, reported a sensitivity of 0.88 and a negative predictive value of 0.98 [60]. The largest series published to date, with 160 procedures for lung cancer staging, reported the following staging values: sensitivity 0.96, negative predictive