Postprandial Recurrent Hemiplegia

Postprandial cerebral infarction

Some neurological diseases are accompanied by autonomic dysfunction. Postprandial hypotension (PPH) is one disorder accompanied by autonomic dysfunction. Although the major symptoms of PPH are fall and syncope, PPH is sometimes overlooked because of its non-specific symptoms, such as dizziness, nausea, and light-headedness. Because PPH could result in decreased cerebral perfusion pressure accompanied by a decrease in blood pressure, PPH may be linked to the risk of hemodynamic stroke or transient ischemic events, especially in patients with chronic cerebral large vessel occlusion/stenosis. Whether chronic cerebral large vessel occlusion or stenosis causes symptomatic ischemic events depends on the patient's compensatory collateral circulation and cerebral vasoreactivity. Therefore, we hypothesized that cerebral blood flow assessment could be essential for stratifying patients at high risk of postprandial cerebral infarction. However, there have been few reports on the association between cerebral blood flow and the occurrence of postprandial cerebral infarction. In a literature review, we identified seven cases of postprandial cerebral infarction. Postprandial cerebral infarction occurs in patients with chronic cerebral large vessel occlusion/stenosis accompanied by cerebral blood flow reduction. Non-pharmacotherapeutic and pharmacotherapeutic approaches could improve postprandial cerebral infarction; however, one patient with poor compensatory collateral circulation and reduced cerebral vasoreactivity experienced recurrent symptomatic episodes even with sufficient medical treatment and needed extracranial-intracranial bypass surgery. Physicians should be aware of PPH as it can complicate neurological disorders. Long-term blood pressure monitoring for the detection of PPH and cerebral blood flow assessment is needed in patients with cerebral large vessel occlusion/stenosis to prevent postprandial cerebral infarction.

Brain perfusion SPECT imaging and acetazolamide challenge in vascular cognitive impairment

Cerebrovascular disease is recognized as a common cause of cognitive impairment and dementia, alone or coexisting with other neurodegenerative diseases, mostly Alzheimer's disease. Vascular cognitive impairment (VCI) is a part of the heterogenous disorders group related to cerebral vessel disease. Although age is one of the most important risk factors for VCI, other common cardiovascular risk factors are also involved. By investigating these risk factors, a high proportion of these cognitive disorders can be prevented and/or delayed. Until now, only treatment of midlife arterial hypertension has been recognized as a preventing factor of vascular dementia. Brain MRI is becoming the method of choice to investigate cerebral vascular pathologies. However, this form of morphological imaging remains inadequate and does not provide useful functional information during VCI exploration, despite which functional imaging such as brain perfusion single-photon computed tomography, performed in baseline conditions and/or after an acetazolamide challenge, is underutilized in VCI exploration. The common strategies for VCI screening have not been standardized until now, and therefore further long-term imaging studies are needed to establish early diagnostic protocols. The present review summarizes the potential benefits of brain perfusion single-photon computed tomography imaging and possible scintigraphic quantification of cerebral hemodynamic reserves in investigation of VCI.

Haemodynamic stroke: clinical features, prognosis, and management

Haemodynamic stroke is a type of ischaemic stroke that is caused by hypoperfusion rather than by embolism or local vasculopathy. It can be caused by systemic diseases such as heart failure or hypotension, but also by severe obstruction of the carotid or vertebral arteries. Patients with haemodynamic stroke or transient ischaemic attack might show specific clinical features that distinguish them from patients with embolism or local small-vessel disease. Ancillary investigations of cerebral perfusion can show whether blood flow to the brain is compromised and provide important prognostic information. Management of patients who have hypoperfusion as the major cause of ischaemic stroke or as a contributing factor is hampered by the lack of clinical trials. Treatment aimed at increasing cerebral blood flow might be considered in selected patients on the basis of information from case series. Further research is needed to define criteria for the diagnosis of haemodynamic stroke and to investigate treatment options in controlled studies.