Section Editor: Sandy Cheng-Yu Chen, M.D.
Taipei Medical University Hospital, Taipei, Taiwan
Secondary neurolymphomatosis is a rare manifestation of non-Hodgkin lymphoma (most commonly B-cell subtype) or leukemia causing infiltration of cranial or peripheral nerves. High index of suspicion in a known case of primary lymphoma is important for timely diagnosis. The classic findings on MRI include diffuse thickening and enhancement of involved cranial nerves. With this patient, post-contrast axial T1-weighted imaging showed diffuse thickening and enhancement of bilateral oculomotor nerves (A, arrows), bilateral trigeminal nerves (B, arrows) and right facial nerve (C, arrow). Similar findings were also noted in bilateral optic, glossopharyngeal, vagus, and hypoglossal nerves (not shown).