Achalasia: Anatomy of the Cardia as It Relates to the Regional Pathophysiology

Abstract

The region of the esophagogastric junction is at the moment an active investigational focus for both clinician and physiologist. An interesting aspect of current study of this area is the lag of anatomic understanding far behind physiologic understanding. There is a need to find out, especially, the relation of the anatomic to the physiologic esophagogastric junction. Proper conclusions can be drawn only from observations made on the living organ. The anatomy of the region is too dynamic to make its features evident in the dead specimen. Achalasia is one of those diseases whose clinical study may permit better understanding of normal regional anatomy and physiology. Here, especially, study of dead organs is not informative. Inspection of the opened esophagus and stomach at the autopsy of a patient with achalasia gives little or no information regarding the anatomic limits of the segment which was narrow during life. Furthermore, study of the anatomy of the cardia in achalasia must be carried out within the lumen of the organ, since the location of the esophagogastric mucosal junction, as defined by the line marking the change in epithelial type, is believed to be paramount in identification of the precise site of narrowing. The present study was made to determine where the line of esophagogastric mucosal junction lies in achalasia in relationship to the abnormal organ configurations as they are visualized roentgenologically. Previous studies have shown that normally gastric mucosa extends up into the “abdominal esophagus,” making it, by definition, part of the stomach (8), and that the esophagogastric mucosal junction normally may migrate a few centimeters toward and away from the brink of the stomach sac, independent of contractions of the regional muscularis propria (9). Material and Method Six adult males, aged from twenty to seventy-six years, with a clinical, roentgenologic, and esophagoscopic diagnosis of achalasia were studied. Four were given the Mecholyl test (6) and all responded in a positive fashion. One of the patients had a fixed direct hiatus hernia in addition to achalasia (Fig. 1). This is the only instance of such a combination that the writer has encountered, and the association is believed to be very rare. In this instance it was, of course, necessary to exclude the possibility that the megaesophagus was due to stricture secondary to the hernia. This was believed to have been done with assurance on the basis of serial esophagoscopic examinations. In addition, although the first fluoroscopic examination during Mecholyl administration showed little response, a repeat study demonstrated swift contraction of the esophagus, with relaxation of the esophagogastric junctional segment.