The angle towards superior direction between chorda tympani nerve and verical segment of FN was 38.6 1.99 (28.5-52.5) . The distance between stylomastoid foramen and the point from which chorda tympani nerve departed FN was 5.99 0.74 (5.01-7.90) mm.

• 鼓索神经与FN垂直段的向上的夹角为38.；6±1