[摘要]目的:通过对枕下乙状窦后锁孔经岩裂-桥脑裂入路的各段结构进行显微解剖学研究，为临床应用提供解剖学资料；方法：对15具30侧正常成人湿头颅标本进行解剖：模拟手术状态下该入路操作，将尸头侧卧位固定在头架上，乳突后横（纵）切口，开2.5cm-3cm骨窗，切开硬脑膜，测量分开岩裂-桥脑裂前后时手术野显露范围变化，以及三叉、面听、舌咽神经入脑干处暴露情况；显微镜下解剖岩裂和小脑桥脑裂上、下支；对岩裂、桥脑裂上、下支、岩静脉、小脑动脉、三叉、面听、舌咽神经入脑干处等相关研究对象进行测量、照相。结果：该入路可显露的解剖结构上至天幕前侧缘，下到枕骨大孔颈静脉结节，内侧到桥脑和中脑的侧方。可显露桥小脑角区包括岩静脉、小脑上中下三个神经血管复合体。岩裂-桥脑裂分离前后距离在统计学具有差异性。结论：该入路是对经典乙状窦后入路的补充和扩大，具有切口小、脑损伤小，充分利用小脑的自然间隙，不牵拉或少牵拉小脑的情况下增加了操作空间；该入路在微血管减压治疗颅神经疾病方面在解剖学上具有可操作性；该入路在同等条件下使后颅窝相关区域的组织结构显露更大，为桥小脑角区占位性病变的切除提供了解剖学空间。

[Abstract] Objective: By microanatomy?research on structures in various sections of suboccipital retrosigmoid?Keyhole via approach of petrosal fissure and cerebello-pontine fissure， so as to provide anatomy data for clinical application.Methods: 15 wet head specimens of 30 normal adults were dissected: the approach operation was simulated， the cadaveric heads were fixed onto head shelf in lateral?position， retromastoid?transverse (vertical) incision was adopted， then a bone window of 2.5cm-3cm was opened， to incise endocranium and measure change of operation field exposure scope， exposed situations of trigeminal?nerves， facial?and auditory nerves and glossopharyngeal nerves at place where such nerves enter brainstem before and after separation of petrosal fissure and cerebello-pontine fissure； petrosal fissure and ramus?inferior and ramus?superior of cerebello-pontine fissure were dissected under microscope； research objects concerninig petrosal fissure， ramus?inferior and ramus?superior of cerebello-pontine fissure， petrosal?vein， cerebellar?arteries， trigeminal?nerves， facial and auditory?nerves and glossopharyngeal nerves at place where such objects enter brainstem were measured， and photos were taken.Results: The exposed anatomical structures by this Surgical approach: upwards to tentorial edge， downwards to foramen magnum jugular tuberculum， inwards to lateral side of pons?and midbrain. Cerebellopontine?angle?area including petrosal?vein， upper， middle and lower neurovascular?territories of cerebellum were exposed. Distance between before and after separation of petrosal fissure and cerebello-pontine fissure is of statistical difference.Conclusion: This Surgical approach is the supplement and enlargement of typical retrosigmoid?approach，with small incision and less brain injury， it can fully utilize the natural space of epencephalon， so as to increase operation space on the premise of not pulling or less pulling epencephalon； this Surgical approach is operable in anatomy in microvascular decompression treatment of cranial nerve disease，this Surgical approach can make the structures in relevant area of posterior cranial fossa more exposed， to provide anatomy space for excision of space-occupying lesions in cerebellopontine angle area.