Answers to Axial MRI Quiz:

#1) Vertebral body of L4 (disc really isn't seen well--it a cut above this view).

#2) Exiting L4 nerve root.

#3) Traversing L5 nerve root. (you can also see the traversing S1 roots as well more posteriorly.)

#4) Thecal sac of the cauda equina.

#5) Facet joint.

#6) Errector Spinalis Muscle.