An angiographic study of the effects of encephalo-duro-arterio-synangiosis (EDAS) in 27 children with moyamoya disease is reported from the Departments of Radiology and Neurosurgery, Tokyo Medical and Dental University, Tokyo, Japan. Comparing pre- and post-operative angiograms, the development of collaterals from the external carotid arterial system into the middle cerebral artery territory was excellent in 16 of 54 cerebral hemispheres after EDAS, good in 25 and poor in 13. The development of collateral vessels from the ECA to the MCA territory increased with the severity of the stenosis of the ICA on preoperative angiograms, but in most advanced stages the development of collateral supply was less marked. The development of collateral vessels was associated with a decrease of abnormal net-like vessels. Stenosis in the ICA had progressed on 12 of the 54 cerebral hemispheres as compared with preoperative angiograms. 
COMMENT. This study suggests that EDAS for childhood moyamoya disease should be performed as early as possible so that the development of irreversible ischaemia and permanent neurological defects may possibly be prevented.
Cerebral blood flow reactivity to hyperventilation in children with moyamoya disease was studied at the Department of Neurosurgery, Hokkaido University School of Medicine, Sapporo, Japan . CBF was measured by single photon emission CT (SPECT) in 11 children divided into bypass and non-bypass groups. There was some hemodynamic insufficiency in the frontal lobes of the non-bypass group who underwent procedures such as EDAS. The reduction of CBF was less after hyperventilation, especially in the frontal lobes of the bypass group in which a much better collateral blood flow occurs.