Aneurysm surgery in Asia--Japanese situation

This report is based on the results of the questionnaires conducted for the Japan Stroke Surgery Meeting 1996 (President: S. Kobayashi). The questionnaires were sent to all neurosurgical training institutions approved by The Japan Neurosurgical Society, numbering 959. The response rate was 54.2% (520 institutions). All statistics dealt with cases from January 1995 to December 1995. The total number of aneurysm surgery performed was 13,166. The average operative case number per institution during the year was 25. About 20% of the institutions exceeded 35 cases. Of all operative cases, 76.3% were ruptured aneurysms and 23.7% were nonruptured. Giant aneurysms were 2.9%; dissecting aneurysms 2.4%. Surgical procedures performed were clipping in 90.3%, wrapping in 5.2%, proximal ligation 1.6%, and bypass in 0.7%. Intravascular surgery was performed for 2.3% of the cases. Sugita clips were mainly used in 80.5% of the institutions, Yasargil clips in 6.6%, and both in 12.9%. For anterior communicating artery aneurysms pterional approach was mainly used in 81.0% of the institutions, interhemispheric in 7.2%, and both in 11.7%. For basilar terminal aneurysms, pterional approach was mainly used in 88.3% of the institutions, subtemporal approach in 6.6%, and both in 5.1%. The nonoperative cases included 24.9% of the ruptured aneurysms, 31.7% of the unruptured aneurysms, 38.4% of the giant aneurysms, and 52.1% of the dissecting aneurysms. The above statistics suggest that aneurysms are treated in Japan in most training institutions and that open surgical treatment is still the main procedure of choice.