Answer of May 2000

Clinical History:

Young male with sudden onset of severe occipital headache.

Figure 1 MRI (T1WI)
Figure 2 MRI (T2WI)
Figure 3 (MRA)

What is your diagnosis?

                            Figure 1                                                            Figure 2

                            Figure 3

Diagnosis:

Vertebral artery dissection with lateral medullary syndrome

Discussion:

Figure 1 T1WI shows a hypointense focus in the left lateral medulla. A high signal crescent rim is noted in the wall of the left vertebral artery.

Figure 2 The medullary lesion shows high signal intensity on T2WI.

Figure 3 MRA demonstrates luminal narrowing in the left vertebral artery.