Editing Trigeminal nerve (section)

==Clinical significance==
*[[Trigeminal neuralgia]]
*[[Cluster headache]]
*[[Migraine]]
===Lateral medullary syndrome===
{{Main|Lateral medullary syndrome}}
[[Lateral medullary syndrome]] (Wallenberg syndrome) is a clinical demonstration of the anatomy of the trigeminal nerve, summarizing how it processes sensory information. A stroke usually affects only one side of the body; loss of sensation due to a stroke will be lateralized to the right or the left side of the body. The only exceptions to this rule are certain spinal-cord lesions and the medullary syndromes, of which Wallenberg syndrome is the best-known example. In this syndrome, a stroke causes a loss of pain-temperature sensation from one side of the face and the other side of the body.

This is explained by the anatomy of the brainstem. In the medulla, the ascending [[spinothalamic tract]] (which carries pain-temperature information from the opposite side of the body) is adjacent to the ascending spinal tract of the trigeminal nerve (which carries pain-temperature information from the same side of the face). A stroke which cuts off the blood supply to this area (for example, a clot in the posterior inferior cerebellar artery) destroys both tracts simultaneously. The result is a loss of pain-temperature (but not touch-position) sensation in a "checkerboard" pattern (ipsilateral face, contralateral body), facilitating diagnosis.

===Sensory neuronopathy===
[[Sensory neuronopathy]] (also known as sensory ganglionopathy) is a type of peripheral neuropathy in which sensory nerve cell bodies in the [[dorsal root ganglia]], commonly including the [[trigeminal ganglion]] of the trigeminal nerve, are damaged due to a variety of mechanisms leading to sensory symptoms such as [[parasthesias]], [[dysesthesia]]s, or [[hyperalgesia]] in the affected nerve distribution including the distribution of the trigeminal nerve.<ref name="Amato 2020">{{cite journal |last1=Amato |first1=Anthony A. |last2=Ropper |first2=Allan H. |title=Sensory Ganglionopathy |journal=New England Journal of Medicine |date=22 October 2020 |volume=383 |issue=17 |pages=1657–1662 |doi=10.1056/NEJMra2023935|pmid=33085862 }}</ref>