Microembolic signals predict cerebral ischaemic events in patients with moyamoya disease
Background and purpose
Recent studies found that microembolic signals (MESs) could be detected by transcranial Doppler in patients with moyamoya disease. However, the clinical significance of MESs in moyamoya disease remains unclear. Our aim was to investigate whether the MESs could predict cerebral ischaemic events in patients with moyamoya disease.
Fifty-four consecutive patients with moyamoya disease were recruited. MESs were monitored by transcranial Doppler for 30 min in the bilateral middle cerebral arteries of each patient on admission. Patients were followed up for 1 year. The primary end-point was cerebral ischaemic events including stroke and transient ischaemic attack (TIA).
MESs were detected in 11 (20.4%) patients, with a frequency of 11 (10.2%) in 108 hemispheres. Logistic regression analysis revealed that previous ischaemic events within 3 months were associated with the presence of MESs (odds ratio 4.41, 95% CI 1.11–17.59). During a median follow-up of 384 days, 14 (13.0%) hemispheres had ischaemic events (seven strokes and seven TIAs). Cox regression showed that the hazard ratio for the risk of new ischaemic stroke and TIA in the hemispheres with MESs was 6.84 (95% CI 1.82–25.66) compared with those without, and 10.61 (95% CI 1.66–67.70) for ischaemic stroke alone, after controlling for age, sex, presence of ischaemic events at baseline, Suzuki stages and revascularization surgery.
In patients with moyamoya disease, the presence of MESs is associated with recent ischaemic symptoms and independently predicts cerebral ischaemic events. MES detection may be of potential clinical value in the management of patients with moyamoya disease.