ABSTRACT
Objective To obtain more detailed microsurgical anatomical data and multi-slice helical CT scanning of cochlear aqueduct for the translabyrithine approach. Methods Twenty cadaver heads(40 sides)fixed with formalin were dissected under a microscope ,and cochlear aqueducts were found and measured. Five cadaver heads(10 sides) were scanned by multi-slice helical CT. Results The width of external aperture of cochlear aqueduct was (2.64?0.82)mm. The length of cochlear aqueduct was (8.40?1.35)mm. The distance between cochlear aqueduct and cranial nerves Ⅸ, Ⅹ, Ⅺ, and that between the inferior petrosal sinus was(1.08?0.36 )mm,(2.71?0.63)mm,(4.52?1.25)mm, (1.14?0.46)mm, respectively. The distance between external aperture of cochlear aqueduct and the inferior margin of internal acoustic meatus aperture was (5.53?0.93)mm. The otic capsule segment of cochlear aqueduct could not be demonstrated on the coronal section. The petrosal portion could be demonstrated by both coronal and axial scannings. Conclusion The axial scanning was useful for detecting cochlear aqueduct. Cochlear aqueduct could be regarded as one of the landmarks in translabyrithine approach for cerebellopontile angle operation.