Delineation of the normal esophagus at computed tomography.

It has been accepted by many that the esophagus in its entire length is easy to delineate at CT in most patients due to surrounding fat planes. As this is not the experience of the present authors, the CT of the thorax in 100 normal men and women without mediastinal disease and in good nutritional status was reviewed, to record the relationship between the esophagus and neighbouring structures. In the upper third of the esophagus there is almost never a definite border between its wall and that of the trachea, while a separating border or even a fat plane can be seen to the spine in between 25 and 50 per cent of those tested. The vessels, as a rule, have a fat plane towards the esophagus. The middle part of the esophagus has the same intimate relationship to the trachea and left main bronchus, i.e. almost never any separating border. Two thirds of the cases have no border to the upper part of the pericardium (left atrium), while about 70 per cent have a border or fat plane towards the aorta. The middle and lower third of the esophagus has, as a rule, a distinct border or fat plane to the spine. In about 50 per cent of the patients the anterior wall of the lower esophagus is separable from the pericardium.