What imaging study is best for orbit, apex, and brain?

The orbit can be tricky to image as it is composed of soft tissues and fat, yet surrounded by obstructing bone. In general, however, the orbital contents, globe, and bone are usually best seen with CT scan. When you get back to the orbital apex (where the optic nerve enters the eye-socket) and further back into the brain where bone obscures details, MRI is a superior modality.

These are general guidelines, and all rules are meant to be broken. For example, MRI MRI is better for the viewing enhancement of the optic nerve seen with optic neuritis.

In practice, a CT scan with thin-cut coronas is best for looking at trauma cases as it will show wall fractures, air-fluid levels, and retrobulbar hemorrhages. MRI is better for neurological scans. For tumors, it really depends what you’re looking for.