Acute brain swelling during operations for three patients with moyamoya disease resulting in performance of indirect anastomosis as a substitute for direct anastomosis

: Surgery for the treatment of moyamoya disease includes direct and indirect anastomosis. In the present study, three cases with moyamoya disease, in which acute brain swelling in the operative field occurred just after opening of the dura mater and indirect anastomosis was performed as a substitute for direct anastomosis to terminate the operation earlier than originally planned. They all waked immediately from general anesthesia and showed no neurological deterioration. Computed tomographay of the brain performed just after the operation showed no abnormalities such as acute infarction, hemorrhage, global brain swelling, and local brain swelling. One of the three cases showed signs of having caught a cold before the operation, another manifested allergic rhinitis just before the operation, and the other had taken a long walk and experienced hyperventilation resulting in TIA associated with quadriparesis a day before the operation. Abrupt return from hypocapnea to normocapnea during the induction of general anesthesia was thought to be the cause of the acute brain swelling. It was thought desirable that correction of hypocapnea needed to be performed gradually during the operation in those cases.