Background and purpose: Although intracranial atherosclerotic disease has been highlighted especially in Asian countries, little is known about the stroke mechanism of middle cerebral artery (MCA) stenosis. Patients with MCA stenosis often show acute neurological worsening. However, no study has ever been focused on stroke mechanism and acute neurological worsening in patients with MCA stenosis. We conducted the present study to clarify the relationship between stroke mechanism and acute neurological worsening in patients with MCA stenosis.
Methods: From consecutive acute ischemic stroke patients entered in our hospital, we selected 30 patients who had MCA stenosis. Patient characteristics, clinical course and lesion patterns were correlated.
Results: Acute neurological worsening was observed in 10 patients (30%), of whom 8 patients exhibited poor prognosis. Diabetes mellitus tended to be significantly associated with acute neurological worsening. Subcortical small multiple infarcts, deep border-zone infarcts and striatocapsular infarction tended to be significantly associated with acute neurological worsening.
Conclusion: Two main stroke mechanisms appear to contribute to acute neurological worsening in patients with MCA stenosis. One mechanism is a combination of hypoperfusion and micro-embolism. The other mechanism is occlusion of multiple lenticulostriate arteries by MCA plaque. Clarifying mechanism may help to decide therapeutic strategies.
