LAUSR

Intravascular large B-cell lymphoma (IVLBCL) is a rare type of lymphoma, involving the lumen of predominantly small blood vessels, especially capillaries. The orbit is an uncommon site of involvement for IVLBCL, and diagnosis before autopsy is even more rare as most cases are established post-mortem. Herein, the authors describe a 73-year-old male who presented with 3 weeks of progressive bilateral ptosis and ophthalmoplegia. Computed tomography (CT) and subsequent magnetic resonance imaging (MRI) revealed diffuse abnormal thickening and enhancement of bilateral orbital apices, superior orbital fissures, and cavernous sinus, along with persistent focal opacification of the left frontal and ethmoid sinuses. Infectious and inflammatory workup of serum and cerebrospinal fluid was negative. Ethmoidal sinus and middle turbinate biopsy confirmed intravascular large B-cell lymphoma and the patient was started on R-CHOP chemotherapy regimen.