Persistent migraine aura: new cases, a literature review, and ideas about pathophysiology.

BACKGROUND: Persistent migraine aura without infarction (PMA) is a rare condition that is defined as an aura that lasts longer than 1 week in absence of infarction. Two types of PMA have been distinguished, notably persistent primary visual disturbance (PPVD) and typical aura (TA). OBJECTIVES: This case-based review article describes four new cases of PMA as well as reviews all cases reported, trying to identify relevant associations, in particular with respect to functional investigations. METHODS: We performed a systematic literature search, extending from the period when it was first described (1991) to March 2014. We included all case descriptions of which criteria for PMA formulated in the International Classification of Headache Disorders, second edition, were met. In addition, we described four new cases. RESULTS: We identified 47 cases of PMA, 27 PMA-PPVD and 19 PMA-TA. In one case, there was not enough information to define the type of PMA. The mean age of onset was 30 years, varying from 7 to 74 years. The duration of symptoms varied from 9 days to 28 years. Besides a longer duration in symptoms in the PMA-PPVD group, we could not identify any differences between these groups. Some authors report occipital hypoactivity on Tc99m-hexamethylpropylene amine oxime -single-photon emission computed tomography (Tc99m-HMPAO-SPECT) or fluorodeoxyglucose-positron emission tomography (FDG-PET) in PMA cases, but data are inconsistent. Multiple drugs have been used for the treatment of PMA, usually with little effect. Lamotrigine seems to be the most effective drug. CONCLUSION: Despite the fact that 47 cases of PMA have been reviewed in this paper, many questions remain. The cases that have been described so far show inconsistent data with respect to the results of functional studies as well as treatment effects. The pathophysiology of PMA is still largely a matter of conjecture.

Prognostic factors in carpal tunnel syndrome treated with a corticosteroid injection.

INTRODUCTION: Symptoms often return in patients with carpal tunnel syndrome (CTS) who are treated with a local corticosteroid injection. We aimed to determine prognostic factors for a successful long-term outcome. METHODS: We prospectively followed 113 patients who received an injection for CTS. Clinical, electrophysiological, and ultrasonographic tests were done at baseline, and clinical outcome was evaluated after 1, 3, 6, and 12 months. The primary outcome measure for success was no need for additional treatment (e.g., surgery) within 1 year. RESULTS: After 1 month, most patients improved, but after 12 months 67.4% had surgery. Patients with a successful outcome had a lower median nerve ultrasonographic cross-sectional area (CSA) at the pisiform bone, a lower swelling ratio, and a lower symptom severity score. CONCLUSIONS: Less pronounced median nerve swelling measured by ultrasonography may indicate a less severe stage of CTS, which is more likely to respond to treatment with a corticosteroid injection.

Persistent aura with small occipital cortical infarction: implications for migraine pathophysiology.

OBJECTIVE: The pathophysiology of migraine with aura is thought to be related to cortical spreading depression and cortical hypersensitivity, in which inhibitory interneurons may play a role. Persistent migraine aura (PMA) without infarction is defined as auras that last longer than 1 week in the absence of infarction. We describe a case of persistent aura with a small occipital cortical infarction and discuss implications of this case and PMA for pathophysiological concepts of migrainous auras. METHODS: We present a case and discuss the implications for pathophysiological concepts. RESULTS: The case presented cannot be diagnosed as PMA as the patient was found to have an occipital cortical infarction with hypoactivity on fluorodeoxyglucose-positron emission tomography. Nevertheless, the patient suffered from persistent aura (with infarction). We argue that the infarction may have been responsible for an increased imbalance in one of the primary visual cortex networks that was already hyperexcitable due to the migraine aura condition. CONCLUSION: PMA with occipital infarction has not been reported previously. We believe the findings of the present case and PMA cases reported in the past may support the intracortical disinhibition hypothesis in migraine.