Adult orbital masses: a pictorial review.

This pictorial review is based on cases of orbital tumours collected from the McGill University Health Centre over a period of 3 years. MRI was performed by using a GE 1.5T Signa HD platform unit (General Electric Healthcare, Milwaukee, WI), whereas computed tomographic (CT) images were acquired with a Lightspeed VCT (General Electric, Waukesha, WI). The MR images were acquired with the use of a phased-array surface coil system to improve the signal-to-noise ratio and to provide superior images of the anterior optic pathway. The institutional protocol includes T1- and T2-weighted oblique axial images along the plane of the optic nerves, oblique sagittal T1- and T2weighted images also along the plane of the optic nerves, and true coronal T2-weighted images. If an intravenous MR contrast agent is administered, then fat suppression is used for the axial and coronal T1-weighted images.