Otic vesicle An epithelial sac behind the fifth rhombomere forming the semicircular canals dorsally and the otolith organs ventrally.

耳小囊形成于半规管背面与耳石器官腹面且在第五后脑特殊节状结构后面的一个上皮囊。

Dorsally, the starting point is just proximal to the standard 3-4 radiocarpal arthroscopy portal.

背侧入路时，进入点刚好接近于标准桡腕关节镜3-4号入口处。