In this presentation, we will be covering the radiographic positioning criteria for
the Esophagus.
With the advancements made in digital imaging and the ability to capture clear images during
the radiologist’s fluoroscopic routine, we are seeing less and less facilities which
require these views.
It should be noted that these views are performed after the radiologist’s fluoroscopic evaluation,
and often require administration of additional oral contrast media.
The views we will be covering include the AP or PA view, the obliques, which can be
performed both RAO and LAO, as well as the right lateral.
Before we begin the details for positioning, it is important to mention the evaluation
criteria for each of these views:
Evidence of proper collimation
Esophagus from the lower part of the neck to its entrance into the stomach
Esophagus filled with barium
Penetration of the barium
For this exam, preliminary patient prep is not mandatory.
Exams can be single or double-contrast.
For single contrast exams, either barium or water-soluble iodinated contrast may be used.
The first part of the exam, performed with the radiologist, is a functional study of
the patient swallowing.
For
the AP and PA views (positioning criteria on slide)…
It typically takes 2-3 large swallows of to fill a patient’s esophagus with contrast
for the entire length of the esophagus for this view.
We will discuss specific instructions for drinking in lab.
For the obliques, RAO and LAO are typically performed in the anterior oblique position.
This way, the cup can rest on the table and the patient can comfortably hold the cup of
contrast and minimize the risk of choking or aspiration compared to an attempt to perform
this view in a supine position.
Start the patient in a recumbent position and rotate them 35 – 40 degrees, use a 14
x 17 image receptor with at least a 12 x 17 collimated field or more if you’re able
to.
Collimation should include the lower neck all the way to the GE junction, with the central
ray approximately 2” or 5 cm lateral to the MSP.
In the image on the left, we see three view representation of the esophagus.
Note in the far left view (the AP), the esophagus superimposes the spine, however, when we rotate
the patient for the oblique in the second view, it frees the esophagus from superimposition.
We can also see the indentations here from adjacent anatomy including the aortic arch
and the left main bronchus.
The image on the right is an RAO view with single contrast, without air.
From left to right, we see an oblique distal esophagus view with double contrast.
The barium is used to coat the lining, while the air expands the esophagus.
This creates a superior view of the esophageal structure.
Next is a PA oblique view in RAO position, followed by an AP oblique view in the LPO
position.
We are responsible for hanging these images just as we would any other radiograph in the
anatomical position.
For the lateral view, the patient should be placed in a recumbent position, facing the
radiographer with arms brought forward to avoid superimposition of the arms over the
esophagus in this view.
The central ray should be directed at the level of T5 – T6 and the mid coronal plane.
A 14x17 cassette can be used with at least a 12 x 17 collimated field to include the
lower neck to the gastro-esophageal junction.