[Radiological diagnosis of the ösophagus with special attention to the ösophagogastric transition of the gastro-ösophageal reflux, reflux ösophagitis, hiatal hernias and ösophageal stenoses (author's transl)].

The inferior high-pressure zone acts like a functional sphincter. This is formed in the absence of a muscle correlate, via a regional predominance of the sphincter tone caused by inhibition of activity of the longitudinal muscles through the membrane phreno-oesophagea in the region of the vestibulum gastro-oesophageale. Pressure variations in the vestibulum caused by respiration, are governed by a "rein mechanism". Swallowing produces a brief reflectory breakdown of the inferior high-pressure zone in the longitudinal muscles of the ösophagus via myogenic ventricular stimulus condution. Gastro-ösophageal reflux can be regularly identified by means of suitable x-ray examination technique. Since, however, it is not possible to arrive at a quantitative and qualitative assessment of the reflux via roentgenology, the aim of radiological examination in case of clinical suspicion of reflux is to determine a) the factors favouring reflux, ie hiatal hernia, gastric and duodenal ulcer, stenosis of the pylorus, etc, b) the sequelae of a pathological reflux, eg reflux stenosis, reflux ulcer, brachyösophagus etc, as well as c) to assess the self-cleaning function of the ösophagus. It is possible to definitely identify hiatal hernia by radiology with a well-aimed examination technique, through the intrathoracal displacement of parts of the stomach, of Schatzki's ring, and the superhiatal displacement of the entire vestibulum gastro-oesophageale. It is also regularly possible to identify by serial radiography an organic ösophagus stenosis, using large quantities of barium swallow, although pathogenetic interpretation of the x-ray film may be difficulat. Functional stenosis can be defined by pharmacoradiography and manometry. In clinically suspected reflux ösophagitis, endoscopy and histology will supply more conclusive findings in respect of mucosal assessment than x-ray examination.