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面且在第五后脑特殊节状结构后面的一个上皮囊。

Singular neurectomy (posterior ampullary nere transsection) and posterior semicircular canal occlusion are the 2 specific techniques used in intractable BPP surgery.

单神经切除术（后壶神经）和后半规管闭塞术是应用于良阵发位置眩晕的两种特殊的手术疗技术。

Conclusion: The therapy effect of PRM was superior to postural striction, and all patients should be treated by PRM when the diagnosis of posterior semicircular canal BPPV was uncle.

PRM疗效果明显优于体位限制疗，凡后半规管BPPV诊断明确者均应给予PRM疗。