The protocol will vary a bit depending on the type of injury (i.e. stab wound vs gun shot wound vs MVA) sustained and the area of the body (i.e. knee, spine, humerus) involved. Regardless of the body part involved thin section CT (under 1cm necessary and we prefer .75mm) and close interscan spacing (5mm). The use of IV contrast will depend on whether there is a penetrating injury (i.e. stab wound) and the clinical suspicion (i.e. MVA). If IV is used we typically use 100-120 cc of contrast injected at 4-5cc/sec. Images are typically acquired in the arterial phase. Routine MPR (coronal and sagittal) as well as 3D mapping (MIP, VRT or CR) will be done.

1. The key to a successful study is positioning the patient so they remain still during the study. Communication with the patient is critical.
2. The images should be reconstructed with the largest field of view reasonable for the study. Sometimes the field of view is too small and it is difficult to review the images.
3. Image reconstruction should be done with both soft tissue windows (400/7) as well as high resolution bone algorithm windows which are reviewed at a different window width/center (1500/150). The high resolution bone images are optimal for detecting subtle fractures. The soft tissue windows are best for looking at muscle, soft tissues and the vessels.
4. 3D mapping is ideal especially in cases of complex fractures. MIP imaging is good for vessel mapping and detecting small bleeds while VRT/CR is ideal for looking at bone and soft tissue.
5. When looking at bone with metal in place dual energy CT protocols will be helpful to decrease the artifact present.
6. Areas that can be challenging to scan are the wrist and foot in patients with other sites of injury who can’t be perfectly positioned in the gantry
7. Automated bone removal with editing programs or with dual energy subtraction techniques can be valuable.