The trigeminal nerve is the largest cranial nerve, providing sensory and motor functions. It has three major divisions - ophthalmic, maxillary, and mandibular. The trigeminal ganglion contains the cell bodies of pseudounipolar neurons which relay sensory information from the face to the brainstem nuclei. Trigeminal neuralgia is a painful condition characterized by sudden, severe facial pain that may be triggered by light touch. Herpes zoster ophthalmicus affects the ophthalmic division and can cause eye and skin lesions. Wallenberg syndrome results in loss of sensation in patterns due to a stroke affecting the trigeminal nerve tracts.