Frank Gaillard ◉ ◈

What line is the default axial plane for MRI of the brain?

What line is depicted on this image?

What structure is indicated by the arrow?

In the accompanying axial image from a non-contrast CT of the brain, white matter is indicated by which letter?

In the accompanying axial image from a non-contrast CT of the brain, muscle is indicated by which letter?

In the accompanying axial image from a non-contrast CT of the brain, cerebrospinal fluid (CSF) is indicated by which letter?

In the accompanying axial image from a non-contrast CT of the brain, grey matter is indicated by which letter?

In the accompanying axial image from a non-contrast CT of the brain, blood is indicated by which letter?

In the accompanying axial image from a non-contrast CT of the brain, bone is indicated by which letter?

Which of the following CT window width (W) and level (L) settings would be appropriate for routine non-contrast CT of the brain to easily distinguish grey and white matter?

Which of the following CT window settings would be considered most narrow? 

Why can thin acute intracranial subdural hemorrhages be difficult to identify on routine non-contrast CT of the brain?

Looking at a bone algorithm axial image of the skull/brain using brain window (width 80, level 40) will result in the image appearing... 

Which of the accompanying images represents a CT of the posterior fossa reconstructed using a bony algorithm and displayed with routine brain window (W: 80, L: 40)?

Which of the accompanying images would be best to assess for the presence of an undisplaced base of skull fracture?

Which of the following is NOT an appropriate use of BOLD according to the Radiopaedia style guide?

How many different shades can an 8-bit greyscale image can store?

In the accompanying graphic, that depicts the changes in cerebral perfusion parameters with progressively decreasing perfusion pressure, which letter best identifies successful autoregulation? 

In the accompanying graphic, that depicts the changes in cerebral perfusion parameters with progressively decreasing perfusion pressure, which letter best identifies benign oligemia? 

In the accompanying graphic, that depicts the changes in cerebral perfusion parameters with progressively decreasing perfusion pressure, which letter best identifies the ischemic penumbra?