We joined the annual meeting of AANS held in San Francisco in this April. Dr. Tomita presented a 30-year surgical results of meningioma and discussed the strategies to reduce surgical morbidity and improve the long-term outcome. Dr. Akioka presented his data that cerebral hemodynamics is a key factor to determine post-CEA/CAS cognitive function in patients with carotid artery stenosis. We could enjoy a Peru-style lunch with our friend, Prof. Midori Yenari.