C83_teaching abdominal CT - original and annotated images Title hidden

Welcome to the teaching case for how to read a CT abdomen and pelvis!

A few comments about the scan

  • This is a CT of the Abdomen and Pelvis, Enterography protocol
  • This is a higher quality study than a standard CT. It is performed with a higher radiation dose and larger dose of IV contrast. The slice thickness is 2.5 mm. This provides a really excellent look at the large and small bowel enhancement and vasculature, and also the solid organs.
  • This patient has a good deal of intrabdominal fat, which separates and surrounds structures, helping to see/differentiate better than in a thinner patient.
  • This patient does have hepatic steatosis and a tiny gallstone or cholesterol polyp. The study is otherwise normal.

Please note the following:

(1) The first three series are annotated teaching cases. These are great for reviewing all of the key anatomy on a CT of the abdomen and pelvis. Note that these are not true DICOM (converted from JPEG), so features such as ROI or window/leveling will not work.

(2) The second three series are the original case. These are true full DICOM images and can be manipulated using the built-in PACS features.

(3) The top menu has key PACS features that every student should become familiar with:

  • Manual window/leveling. This allows you to change the image appearance to hone in on soft tissue, bone, lung, arteries, or other structures. This only really works on the original series (not the annotated images).
  • Select preset window/level options. Try and see how lung or bone windows changes the image appearance and allows you to see different structures.
  • Zoom and pan the image.
  • Try basic annotation such as putting arrows on the image, measuring structures, and checking ROI (compare the liver and spleen - does the liver measure at least 40 HU less than the spleen?)
  • Change Layout and show axial/coronal side-by-side, triangulating key anatomy on both views. The reference lines will only work on the original series.

(4) Finally, go through the case using the Report Template, finding each structure listed in the checklist! You'll soon be a pro!