superficial temporal artery - middle cerebral artery ( sta - mca ) anastomosis has been attempted for the prevention of cerebral hemorrhage ; however , its effectiveness is unclear . to clarify the effect of operation on the prevention of cerebral hemorrhage in adult moyamoya disease , we compared postoperative courses between sta - mca anastomosis and conservative therapy . the onset was tia in 6 cases , cerebral infarction in 5 cases , cerebral hemorrhage in 8 cases , intraventricular hemorrhage in 4 cases , convulsion in 3 cases , depression in 1 case , and other symptoms in 3 cases . bilateral sta - mca anastomosis was conducted for 8 cases , and therefore , anastomosis was performed on a total of 23 sides . the postoperative clinical course was observed for more than 5 years after sta - mca anastomosis . cerebral hemorrhage occurred after the operation in 2 sides ( 8.7% ) among 23 sides treated with sta - mca anastomosis . ( table 1 ) these 2 patients had shown cerebral hemorrhage ( 1 case ) and intraventricular hemorrhage ( 1 case ) at the onset . on the contrary , hemorrhage occurred during conservative therapy in 5 sides ( 13.5% ) among 37 non - operation sides ( no significance in 2 test ) . these 5 patients had shown cerebral hemorrhage ( 2 cases ) , intraventricular hemorrhage ( 2 cases ) and transient ischemic attack ( tia ) ( 1 case ) at the onset . cerebral infarction occurred in 3 sides ( 13% ) among 23 sides treated with sta - mca anastomosis . ( table 2 ) these 3 patients had shown cerebral infarction ( 1 case ) , cerebral hemorrhage ( 1 case ) and convulsion ( 1 case ) at the onset . on the contrary , infarction occurred in 2 sides ( 5.4% ) among 37 non - operation sides ( no statistical significance in 2 test ) . these 2 patients had shown tia ( 1 case ) and convulsion ( 1 case ) at the onset . the sta - mca anastomosis operation was performed for 3 out of 6 patients with tia . for one among the 3 patients operated on cerebral hemorrhage in the side of sta - mca anastomosis and the non - operation side . cerebral hemorrhage happened after operation in 2 sides ( 8.7% ) among 23 sides of sta - mca anastomosis . on the contrary , hemorrhage occurred during conservative therapy in 5 sides ( 13.5% ) among 37 non - operation sides ( no significance in 2 test ) . cerebral infarction in the side of sta - mca anastomosis and the non - operation side . cerebral infarction occurred in 3 sides ( 13% ) among 23 sides of sta - mca anastomosis . on the contrary , infarction developed in 2 sides ( 5.4% ) among 37 non - operation sides ( no significance in 2 test ) . the patient was a 42-year - old female , who suffered from left hemiparesis and became comatose when she was 17 years old . an sta - mca anastomosis operation was performed on both sides 6 months after the first attack , and she had been in an independent condition thereafter . she presented with nausea , dizziness and right hemiparesis , and suffered from incomplete right hemiparesis and conjugate deviation to the left side upon admission . 1 ) cerebral angiography revealed that the collateral flow via sta - mca anastomosis and middle meningial artery was poor on the left side , compared with the right side . 2 ) the moyamoya vessels developed more prominently on the left side than the right side . she was treated conservatively and eventually walked independently , but marked aphasia remained . this case seems to show that poor revascularization and remaining moyamoya vessel are related with cerebral hemorrhage . it is suggested that decreasing the moyamoya vessels by adequate revascularization will be effective for preventing cerebral hemorrhage in the future . cerebral angiography 5 days after second attack . left cerebral angiography ( a , lateral view ) and right cerebral angiography ( b , lateral view ) . they revealed that collateral flow via sta - mca anastomosis ( arrow ) and middle meningial artery ( double arrow ) was poor on the left side , compared with the right side . the moyamoya vessels ( arrowhead ) developed more prominently on left side than right side . in bypass surgery for moyamoya disease , rebleeding was less likely to occur in patients who had undergone bypass or some other revascularization surgery . the rebleeding rate was 19.1% in the bypass surgery group in contrast to 28.3% in the conservative treatment group ( no significance ) . rebleeding was observed in 12.5% of patients who underwent bypass surgery and in 38.5% of patients who did not ( no significance ) . in the current series , cerebral hemorrhage occurred in 8.7% of sta - mca anastomosis sides in contrast to 13.5% of non - operation sides . cerebral hemorrhage tended to occur less frequently after sta - mca anastomosis and bypass surgery was suggested to have some beneficial effect in preventing cerebral hemorrhage in adult moyamoya disease . however , it was revealed that sta - mca anastomosis caused poor results for those with brain ischemia . cerebral infarction occurred in 3 sides ( 13% ) among 23 sides treated with sta - mca anastomosis . on the contrary , infarction occurred in 2 sides ( 5.4% ) among 37 non - operation sides . another report mentioned that 20% of patients presented with an ischemic event during the follow - up period after encephalo - duro - arterio - synangiosis .
abstractto clarify the effect of surgery on the prevention cerebral hemorrhage in adult moyamoya disease , we compared postoperative courses between superficial temporal artery - middle cerebral artery ( sta - mca ) anastomosis and conservative therapy . 
 the study subjects were 30 adults with moyamoya disease . 
 unilateral sta - mca anastomosis was conducted in 7 of these 30 cases , and bilateral sta - mca anastomosis was conducted in 8 of these 30 cases . 
 therefore , anastomosis was performed in a total of 23 sides . 
 the postoperative clinical course was observed for more than 5 years after the sta - mca anastomosis . 
 cerebral hemorrhage occurred after operation in 2 sides ( 8.7% ) among the 23 sides that received sta - mca anastomosis . on the contrary , hemorrhage occurred during conservative therapy in 5 sides ( 13.5% ) among 37 non - operation sides ( no significance in 2 test ) . 
 cerebral infarction occurred in 3 sides ( 13% ) among 23 sides treated with sta - mca anastomosis . 
 however , the infarction occurred in 2 sides ( 5.4% ) among the 37 non - operation sides ( no significance in 2 test).cerebral hemorrhage tended to occur less frequently after sta - mca anastomosis , and bypass surgery was suggested to have some beneficial effect in preventing cerebral hemorrhage in adult moyamoya disease . 
 however , it was revealed that sta - mca anastomosis exacerbated the brain ischemia . 
 therefore , strict management is mandatory in the perioperative period .