In our workshops, before we look at abnormal, we always look at the normal appearance of a structure and make sure we understand it well. Without knowing normal, you can’t hope to understand what is abnormal.

So what does a normal lumbar disc look like on MRI and what is the normal degenerative process of a lumbar disc?

• A normal disc has water so..
• Its High signal on T2 Low signal on T1
• It doesn’t enhance

What happens to a disc with age and degeneration?

• As a disc ages and degenerates it looses water and..
• It’s T2 signal progressively decreases
• It’s height progressively decreases

As a disc degenerates, it looses height and T2 signal. This appearance is important to know when we are trying to differentiate degenerative Modic Type 1 changes and Discitis as we will see in upcoming posts.