Teaching NeuroImages: The Trigeminal Pontine Sign: Centripetal Migration of Herpes Virus to the Central Nervous System

A 53-year-old woman with recurrent right lower lip cold sores presented with a 2-year history of hyperesthesia in the right V3 distribution. Brain MRI showed a nonenhancing band-like T2 hyperintensity from the trigeminal root entry zone to the dorsolateral pons (figure). Spinal fluid was negative for oligoclonal bands, HSV1/2 PCR, and varicella PCR/IgG. Repeat MRI after 4 months showed no new lesions. The trigeminal pontine sign reflects possible limited centripetal migration of herpes virus from the Gasserian ganglion to the intrapontine trigeminal fibers and sensory nucleus causing demyelination and cell death.1,2 It must be differentiated from other causes of demyelination like MS.

Read article at journal's website

Related Articles


Your email address will not be published.