Background.-Neuronal intranuclear inclusion disease (NIID) is considered a heterogeneous disease because of its highly variable clinical manifestations. To date, there are no reports of NIID patients presenting with hemiplegic migraine (HM)-like headache, or of HM and NIID co-occurring as comorbidity, and the connection between these 2 seemingly unrelated clinical conditions has yet to be established.Method.-We present a patient with NIID who was previously diagnosed with HM. To determine the pathogenesis of HM in this NIID patient, we systematically reviewed published NIID and HM cases and cataloged them based on their clinical manifestations.Result.-The clinical manifestations of NIID is highly various; however, there is no case reported to date that shows HMlike symptoms or cerebral edema. All documented symptomatic HM cases show vascular dysfunction to various degrees, but none of them has been shown to be correlated with NIID.
Conclusion.-Our patient is the first documented case in which HM and NIID occur simultaneously. Vascular dysfunctions that cause cerebral hypoperfusion and glucose hypometabolism, two of the dominant causes of symptomatic HM, may be associated with the accumulation of eosinophilic hyaline inclusions that cause NIID. However, the existence of inclusions may also alter neuronal behavior and indirectly cause cerebral hypoperfusion and glucose hypometabolism. Further research andobservations are needed to examine the relationship between HM and NIID. Key words: hemiplegic migraine, sporadic hemiplegic migraine, neuronal intranuclear inclusion disease Abbreviations: CNS central nervous system, CSF cerebrospinal fluid, CT computed tomography, DWI diffusion-weighted imaging, EEG electroencephalography, FHM familial hemiplegic migraine, HM hemiplegic migraine, ICHD International Classification of Headache Disorders, MRA magnetic resonance angiography, MRI magnetic resonance imaging, NIID neuronal intranuclear inclusion disease, PET positron emission tomography, PWI perfusion-weighted imaging, SHM sporadic hemiplegic migraine, SWI susceptibility weighted imaging (Headache 2020;60:382-395) Headache