abdomen Flashcards
What are the projections included in an acute abdominal series?
- Antero-posterior projection - Supine abdomen
- Antero-posterior or postero-anterior - Erect abdomen
- Erect chest X-ray
What is the centering point for an antero-posterior projection of the supine abdomen?
- Center in the midline at the level of the iliac crest
- to the center of the image receptor when the upper border is at the level of the Xiphisternum.
How should a patient be positioned for an antero-posterior projection of the supine abdomen?
- Patient is supine in the center of the x-ray couch and centered to the bucky.
- Knees and shoulders are slightly raised to straighten the lumbar arch and bring the abdominal contents close to the film.
- ASIS should be equidistant from the table top.
- Arms are abducted, resting at the patient’s sides.
Where should the upper border of the image receptor be placed for an antero-posterior projection of the supine abdomen?
The upper border of a 35 x 43 cm image receptor should be at the level of the Xiphisternum.
Lower border at the level of symphysis pubis
Why is an antero-posterior projection of the erect abdomen taken?
It is taken to look for fluid levels and free gas (air-fluid levels), especially when obstruction is suspected, and a diagnosis cannot be made from the supine image.
Why is an erect chest X-ray included in a routine abdominal series?
- It shows a small pneumoperitoneum more clearly than an erect abdomen.
- An acute abdomen may be complicated if there is also chest pathology (e.g., pleural effusions in acute pancreatitis).
- Some signs and symptoms of chest pathology may mimic an acute abdomen (e.g., pneumothorax, pulmonary embolus, pericarditis).
How should a patient be positioned for an antero-posterior projection of the erect abdomen?
- Patient stands against the erect bucky.
- Image receptor is adjusted to include the symphysis pubis below and the diaphragm above (top of IR to Xiphisternum).
What can an erect chest X-ray show in the context of an acute abdomen?
- Perforation - free gas under the diaphragm.
- Sub-phrenic abscess.
When are decubitus views used in an acute abdomen series?
- Decubitus views are used instead of an AP abdominal erect projection when the patient is unfit to stand.
What should the IR include in a left lateral decubitus view?
The IR must include the symphysis pubis and diaphragm, with the top of the IR at the level of the Xiphisternum.
What is the preferred decubitus view for an acute abdomen, and why?
The left lateral decubitus view is preferred because it shows free air or gas away from the stomach, contrasted against the liver.
How should a patient be positioned for a left lateral decubitus view?
- Patient lies on the left side.
- Raised on non-opaque pads.
- Arms above the head or well out of the way of the abdominal area.
- Knees slightly flexed for immobilization.
- IR positioned vertically at the back, supported with foam pads and sandbags.
What is the centering point for a left lateral decubitus view?
Center in the midline at the level of the iliac crests or to the middle of the image receptor.
When is a dorsal (supine) decubitus view used?
It is used for very seriously injured or seriously sick patients who are unable to turn onto their side.
How should a patient be positioned for a dorsal (supine) decubitus view?
- Patient is supine and raised on pads.
- Arms well up.
- Top of the 35 x 43 cm cassette at the level of the Xiphisternum.
- Position to include the diaphragm and the symphysis pubis.
- IR exposed on arrested expiration.
