Long-term effects of indirect bypass surgery on collateral vessel formation in pediatric moyamoya disease.
OBJECTIVE
The authors investigated whether revascularization surgeries in children with moyamoya disease could reduce abnormal collateral formations in the posterior circulation; long-term follow-up angiography was performed to assess status.


METHODS
In six patients who underwent indirect bypass surgery in childhood, long-term follow-up angiography studies were obtained between 7 and 12 years after surgery. All six patients presented with ischemic symptoms at onset of disease between 2 and 7 years of age. Ischemic insults did not occur after surgery in any patient. In five cases, the angiographically documented stages advanced bilaterally, and in three cases the angiography revealed nearly occluded intracranial carotid arteries bilaterally. In all sides in these five cases, the collateral circulation through the grafts developed well, and collateral formation from the lenticulostriate arteries and from the anterior choroidal artery decreased according to the natural advancement of disease. There was no reduction in the collateral formations from the posterior circulation, however, in four of these five cases.


CONCLUSIONS
Although the data cannot directly indicate that the patients in this study remain at potential risk of developing hemorrhage in the future, these facts should be considered when evaluating the efficacy of revascularization surgeries, because the hemorrhagic potential of abnormally dilated collateral vessels from the posterior circulation would increase as the advancement of the disease.
Goda
Makoto
M
Department of Neurosurgery, Oita Medical University, Hasamamachi, Oita, Japan. gochan@sb4.so-net.ne.jp
Isono
Mitsuo
M
Ishii
Keisuke
K
Kamida
Tohru
T
Abe
Tatsuya
T
Kobayashi
Hidenori
H
D001921:Brain / Q000098:blood supply*; D002533:Cerebral Angiography; D002544:Cerebral Infarction / Q000000981:diagnostic imaging / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D003097:Collateral Circulation / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002546:Ischemic Attack, Transient / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D009072:Moyamoya Disease / Q000000981:diagnostic imaging / Q000601:surgery*; D011183:Postoperative Complications / Q000000981:diagnostic imaging*; D016896:Treatment Outcome