Brain Anatomy (MRI)

1-The MRI is more sensitive than CT.

2-Sequence of the MRI could be T1 or T2.

3-In T1 the cerebro-spinal fluid is black.

4-In T2 the cerebro-spinal fluid is white.

5-MRI can do axial, coronal and sagittal images.

6-How you can differentiate between CT image and MRI T1 image.

-Both show cerebro-spinal fluid black.

-Look to the bone, it appears black in MRI (non mobile protons)while it appears white in CT.

7-At the level of fourth ventricle, we can see trigeminal nerve as a thin line arising from pons then piercing the skull base to reach the para sellar area (not seen by CT).

8-Value of MRI sagittal view:

Look to the brain from up down.

-Look to the venous sinuses.

-Lobes for anatomical localization of the lesion.

-Corpus callosum.

-Pituitary gland.

-Cranio-cervical junction.

-MRI take slices from left to right in sagittal image.

9-Value of coronal view:

-Used for pituitary gland and its stalk.

-Evaluation of carotid vessels and their branches.

-Take care vessels appeared black due to rapid moving of blood inside it.

-Structures appear black in MRI are

Bones due to non mobile hydrogen protons.

Air due to absence of protons.

Vessels due to rapid moving of blood. 

-MR angiogram without injection of contrast.