CASE 47: MRI ORBIT

Young Male. Proptosis.

DIAGNOSIS

Iso-hyperintense orbital mass, with extra and intra conal components

ORBITAL LYMPHOMA

RAD PEARLS

* Commonest orbital tumor

* Association with  Chlamydia psittaci infection has been decribed with MALT Lymphomas

* Primary orbital lymphoma (by definition) is Stage 1E disease

* MRI is best with hypointense signals on T1 (iso to hypo to muscle), and iso-hyperintense signals on T2, restricted diffusion on DWI and homogenous enhancement

* Extraocular muscles are usually not affected, and though engulfed may not be involved (as seen in case above)