Unilateral or bilateral facial or oral pain in the distribution(s) of one or more branches of the trigeminal nerve, caused by a disorder other than those described above, with other symptoms and/or clinical signs of trigeminal nerve dysfunction.
- Unilateral or bilateral facial pain in the distribution(s) of one or both trigeminal nerve(s) and fulfilling criterion C
- A disorder, other than those described above but known to be able to cause painful trigeminal neuropathy with clinically evident positive (hyperalgesia, allodynia) and/or negative (hypaesthesia, hypalgesia) signs of trigeminal nerve dysfunction, and affecting one or both trigeminal nerves, has been diagnosed
- Evidence of causation demonstrated by both of the following:
- pain is localized to the distribution(s) of the trigeminal nerve(s) affected by the disorder
- pain developed after onset of the disorder, or led to its discovery
- Not better accounted for by another ICHD-3 diagnosis.
Painful trigeminal neuropathy may develop secondary to multiple sclerosis, space-occupying lesion or systemic disease, with only the clinical characteristics (quality of spontaneous pain, evoked pain and presence of sensory deficits) distinguishing between 18.104.22.168 Secondary trigeminal neuralgia and 13.1.2 Painful trigeminal neuropathy.
13.1.2 Painful trigeminal neuropathy caused by a connective tissue disease or hereditary disorders is usually bilateral but may begin asymmetrically and occasionally present with paroxysmal pain superimposed on the background pain. Patients will eventually develop bilateral sensory deficits and continuous pain, which clarify the diagnosis. MRI is normal, but trigeminal reflexes are invariably delayed or absent.