The main goal to performing a transverse ultrasound scan is to be able to identify an appropriate interspace. In order to interpret when you are in an interspace it is first important to be able to identify when you are not in an interspace.
The following anatomical structures can be seen outside of the interspace:
A vertebral interspace is usually characterised by being able to see the following structures:
Slide the probe up and down to view these structures at different interspaces.