CT perfusion in acute confusional migraine

Abstract

Acute confusional migraine (ACM) is a rare migraine variant characterized by headache associated with altered mental status and speech difficulties. A 50-year-old headache-suffer male was admitted to our Hospital due to severe headache, vomiting, confusion, agitation, disinhibition and dysphasia. He performed brain CT, CTA and CTP which showed hypoperfusion in the left temporal lobe without an ischemic core. All these symptoms completely resolved the following day, with residual amnesia for the episode. Laboratory blood test and cerebrospinal fluid analysis were normal. Brain MRI showed a puntiform hyperintensity on DWI in left parietal lobe, not confirmed on follow-up MRI. Baseline EEG showed diffuse left-side dominant slow waves, with subsequent improvement. ACM is a rare migraine variant and often a challenge for clinicians to diagnose appropriately, also because there are no classification criteria. It is an exclusion diagnosis and some dangerous causes of confusion (e.g., epilepsy, ischemia, hemorrhage, neoplasm and encephalitis) should be ruled out. Data from previous published reports showed that ACM is characterized by decreased cerebral blood flow in the left splenium region and medial temporal lobe on SPECT scans. In our patient we found hypoperfusion on the left temporal lobe without an ischemic core on brain CTP. The more widespread use of brain CTP in an acute setting together with clinical course and blood and CSF results could help physicians to raise the doubt of this rare clinical entity avoiding misdiagnosis or excessive diagnostic testing.