**6. Comments**

Most of the time, the few authors who described the clinical experience of removal of the mucosa and submucosa of the esophagus by invagination with preservation of the muscular tunic performed median frenotomy with section of the diaphragmatic pillar for greater exposure of the esophagus, and thus to be able to dissect the mucosa in greater detail extension [62, 63].

Opening the diaphragm with greater esophageal dissection at the mediastinal level would not correspond to one of the objectives recommended by the technique we propose: to avoid mediastinal involvement. Thus, in no patient in the series studied, this exposure became necessary, since the dissection of the mucosa in relation to the tunica muscularis, performed along the entire length of the abdominal esophagus and in almost the entire length of the cervical esophagus, was sufficient for the removal of the specimen with the surgical procedure in all the cases studied, according to intraoperative macroscopic evaluation.

This easy removal of the mucosa through the submucosal plane must occur due to the histological characteristics of the esophagus tunics. The mucosa consists of a resistant stratified flat epithelium, and the submucosa has a low proportion of collagen fibers and a large amount of elastic fibers, making it more flexible and looser [62].

Another objective of this procedure is that in the entire resection of the mucosal/submucosal cylinder, both the prophylaxis and the eradication of all chronic inflammatory lesions detected due to the long-term food stasis and, as a consequence, a malignant potential, have occurred as has been shown in some series of patients with advanced megaesophagus, with a frequency ranging from 3–10% [3, 27, 49, 50]. The presence of carcinoma was not found in any of the samples, although in all cases, there was moderate to intense inflammatory infiltrate and in 12.9% leukoplastic lesions.

Mediastinal hemorrhage is not a common occurrence after esophagectomy without thoracotomy. However, a high incidence of morbidity and mortality is expected when hemorrhage occurs [29, 33, 42, 44]. This can occur due to direct injury to the azygos vein and esophageal vessels directly from the aorta, which associated with pleural involvement can progress to hemothorax in up to 25% of cases. This complication usually requires immediate repair by thoracotomy, often unsuccessfully, a fact that did not occur in any of the cases of esophageal mucosectomy technique surgeries used.

Another complication that can occur with transhiatal esophagectomy is hydropneumothorax with an index variable from 22.2% to 83.3%, because the dissection of the esophagus at the mediastinal level can result in the opening of the pleura [29, 33, 42, 44–46]. The reduced incidence of pleuropulmonary complications and none at the mediastinal level in the series of patients in our study, justifies once again the proposed technical procedure.

#### *Surgical Treatment of Esophageal Advanced Achalasia DOI: http://dx.doi.org/10.5772/intechopen.99944*

Recently, Aquino et al. [67] compared intra- and postoperative complications in 229 patients with advanced megaesophagus undergoing esophageal mucosectomy and transhiatal esophagectomy. Pleural effusion with or without hemothorax was more frequent in patients submitted to transhiatal. Other complications of great morbidity occurred only in the group submitted to transhiatal, like massive hemothorax which developed in 6 (5%) patients, among which two died. Also in the transhiatal groups, 3 (2%) patients developed tracheal injury and one of them died.

Another important aspect to consider with this technique is the possibility of excessive bleeding when removing the mucosa and submucosa. However, both in the intra- and immediate postoperative evaluation, all parameters showed that the patients evolved hemodynamically stable and few required blood replacement. Paricio et al. [62] demonstrated in their series that the amount of blood did not exceed 100 mL by aspiration drainage from the tunica muscularis in 3 patients who had undergone mucosectomy due to adenocarcinoma of the cardia. Other authors who also performed this technique demonstrated that although the mean blood volume eliminated intraoperatively was between 700 to 800 mL, in none of the patients hemodynamic instability developed [63]. Aquino et al. [64], demonstrated in an experimental study in dogs, absence of active bleeding 2 hours after mucosectomy.

These findings confirming the minor bleeding with the use of the technique described above may be due to the characteristics of the esophagus intramural blood supply. According to Potter & Holyoke [68], the segmental arterial branches of the aorta penetrate the longitudinal and circular muscle bundles of the esophageal wall and further subdivide into the highly distensible tunica submucosa. Thus since these vessels have a much narrower caliber than the esophagus arteries it is supposed that spontaneous hemostasis occurs.

In the late evaluation of the 85 patients whom we were able to follow-up up for 5 years, the validity of said operative procedure was evidenced once again, because, as demonstrated, the four symptoms recommended by Eckardt et al. score [66] had an evident significance between the pre- and post-operative period with good evolution of the patients. Dysphagia stands out, which in the preoperative period all patients exhibited this symptom daily and/or at every meal and in the postoperative period, the majority had normal swallowing or very occasional dysphagia. In addition, all patients experienced a very expressive weight gain with 27 patients exhibiting more than 25 kg of weight gain.

And also when we evaluated the mean sum of symptoms at the same time of follow-up, the good evolution of the patients was once again confirmed, as preoperatively it was 9.6 and post-operatively it decreased significantly to 1.9.

Until the presentation of our study, no series had demonstrated any study that could compare in the preoperative and postoperative esophagectomy period performed for advanced achalasia of chagasic or idiopathic origin, the assessment of the sum of the symptom score proposed by Eckardt et al. [66]. Only this author's study is reported with 54 patients with idiopathic achalasia, but who underwent pneumatic dilation with a mean follow-up of 13.8 years after the procedure. These authors recommended that in order to have clinical remission of the disease after treatment, it is necessary that the symptoms have completely disappeared or that the total sum of the score does not exceed 3, a fact that was very evident in our series.

Thus, we conclude that esophageal mucosectomy with preservation of the muscular tunic for the treatment of advanced esophageal achalasia is an adequate procedure due to the low incidence of pleuropulmonary complications, absence of mediastinal complications and good resolution of symptoms in the long term. We thus hope to offer a new alternative for those who consider the esophagus resectability as the best form of therapy for advanced achalasia.
