title: Nationwide co-operative study of intracranial aneurysm surgery in Japan.
abstract: A cooperative study was made of 4750 intracranial aneurysm cases collected from 133 neurosurgical clinics in Japan by letter inquiry for the period of 2 years from January 1974 to December 1975. Among them, 4124 cases (87%) had a single aneurysm, and 626 cases (13%) had multiple ones. Direct radical surgery was done in 78% of all cases, carotid ligation in 2% and non-surgical treatment in 17%. Direct surgery in a mortality rate of 15% for ruptured aneurysm cases and 7% for nonruptured cases. Radical surgery within 24 hours after rupture had a mortality of 51%, while those within 1 week and 2 weeks were 39% and 30% respectively; grade I or II patients, however, showed much better surgical results even in early operations. The neurosurgical clinics included in this study were spread throughout most of Japan. Micro-surgical technic was already in use of aneurysm surgery at the time of this study in Japan.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003625:Data Collection; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D002532:Intracranial Aneurysm / Q000453:epidemiology / Q000601:surgery* / Q000628:therapy; D007564:Japan; D008297:Male; D008875:Middle Aged; D012306:Risk; D012422:Rupture, Spontaneous; D013997:Time Factors