Source localization of the re-build up phenomenon in pediatric moyamoya disease-a dipole distribution analysis using MEG and SPECT.

OBJECTS: The "re-build up" phenomenon is a pathognomonic finding induced after hyperventilation in pediatric moyamoya disease, and is closely related to ischemic attacks. However, its precise mechanism remains unknown.

METHODS

In this study, MEG, MRI, and SPECT were used to clarify its mechanism in 4 children with moyamoya disease. Cerebral blood flow before and after acetazolamide administration was measured. Spontaneous magnetic brain activity was measured using a whole-head MEG system. The quantified dipole distribution was shown on 3D-MRI.

RESULTS AND

CONCLUSION

The original current dipoles of the "re-build up" slow waves were predominantly located in the deep cortical sulci in the area with impaired reactivity to acetazolamide. The results suggested that the re-build up waves derive from the deep cortical sulci due to the reduction in the cerebral perfusion reserve.