(来学网)经正中矢状面,正常小脑扁桃体可突入枕骨大孔下不超过
  • A.
    (来学网)1mm
  • B.
    (来学网)2mm
  • C.
    (来学网)3mm
  • D.
    (来学网)4mm
  • E.
    (来学网)5mm