A rare case of short-lasting unilateral neuralgiform headache with conjunctival injection and tearing with progression to neuromyelitis optica spectrum disorder

Symptomatic trigeminal autonomic cephalalgias in neuromyelitis optica spectrum disorders

BACKGROUND

The pathophysiology of trigeminal autonomic cephalalgias (TACs) is poorly understood at present. Symptomatic TACs are rarely reported in neuromyelitis optica spectrum disorders (NMOSD). To better clarify this distinct clinical manifestation in NMOSD and to investigate its possible pathophysiology, we reviewed articles describing such cases including our own case.

METHODS

We performed a search of all clinical studies of TACs in NMOSD published up to September 1st, 2022. We put no restrictions on the year of English publication in our search. The following keywords were searched: trigeminal autonomic cephalalgias, cluster headache, short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT), short-lasting unilateral neuralgiform headache with autonomic symptoms (SUNA), hemicrania continua, paroxysmal hemicrania, neuromyelitis optica, neuromyelitis optica spectrum disorder, Devic's disease.

RESULT

We reviewed six cases (five published reports and our own case study) that fulfilled the diagnosis of NMOSD and TACs. Four of them were SUNCT, one was SUNA, and one was paroxysmal hemicrania. In three of these cases, headache was the initial sole manifestation. Only one case had a good response to routine TACs' treatment. All these patients had lesions in the medulla oblongata and cervical cord. Three cases' TACs were side-locked, and two of them had a left dorsolateral medulla oblongata lesion that corresponded with the left side TACs, while three cases' headaches happened on either side of the head. The phenomenon could be explained by the activation of trigeminal-autonomic reflex and ephaptic coupling.

CONCLUSION

TACs could be the initial sole brainstem manifestation of NMOSD. An underlying cause for SUNCT/SUNA should be considered, especially if there is a limited response to anti-epileptic medication. The activation of trigeminal-autonomic reflex and ephaptic coupling might be the underlying mechanism of symptomatic TACs in NMOSD.

[A case of neuromyelitis optica spectrum disorder in which headache preceded visual field disturbances by 2 months]

A quinquagenarian woman visited our hospital due to experiencing headache around the right upper eyelid for the previous 2 months. T₂-weighted MRI of the head showed multiple high-signal-intensity lesions in the corpus callosum and bilateral corona radiata. She was thought to have an autoimmune disease and was treated with steroid pulse therapy, but the light reflex of the right eye diminished and the patient developed inferior horizontal hemianopsia. T₂-weighted orbital MRI showed an enlarged right optic nerve, a high-intensity signal in the superior half of the optic nerve, and an enhancing effect. She also tested positive for anti-aquaporin 4 antibodies, so she was diagnosed with neuromyelitis optica spectrum disorder (NMOSD). This case shows that headache can be an initial symptom of NMOSD and that clinicians should consider NMOSD when attempting to diagnose patients presenting with headaches.