Unilateral clear hairy tongue sign.

A 53-year-old woman with history of paroxysms pain in the maxillary and mandibular right regions, with trigger zones on the nose wing and right tongue, and ipsilateral clear hairy tongue sign (Figure 1A). Following microvascular decompression surgery targeting a trigeminal nerve emergence vascular loop1, there was complete relief of pain and disappearance of the sign (Figure 1B). Hairy tongue discoloration is attributed to hypertrophy of keratinized filiform papillae that do not renew due to lack of mechanical stimulation in order to avoid pain2. We emphasize that pain elimination and return to normal tongue color are indicative signs of therapeutic success.