MRI-TERMINOLOGY

SUMMARY

When describing most MRI sequences we refer to the shade of grey of tissues or fluid with the word intensity, leading to the following absolute terms:

1. High signal intensity ⟹ white
2. Intermediate signal intensity ⟹ grey
3. Low signal intensity ⟹ black

Often we refer to the appearance by relative terms:
1. Hyperintense ⟹ brighter than the thing we are comparing it to
2. Isointense ⟹ same brightness as the thing we are comparing it to
3. Hypointense ⟹ darker than the thing we are comparing it to



Images: The above images shows a lesion that is isointense on T1W on the left, and hyperintense on T1W with gadolinium on the right.

Reference(s)

Furman, Michael B., and Leland Berkwits. Atlas of Image-Guided Spinal Procedures. Elsevier, Inc, 2017.
Horowitz AL. MRI Physics for Physicians. Springer Science & Business Media. (1989) ISBN:1468403338.
Mangrum W, Christianson K, Duncan S et-al. Duke Review of MRI Principles. Mosby. (2012) ISBN:1455700843.