Skull negative

Skull base film is a photograph of the bottom of the skull to observe the condition of the cranial fossa in the skull base. Skull base film is used to observe the condition of the cranial fossa in the skull base. Some structures of the posterior cranial fossa, such as oval holes, spinous holes, ruptured holes, inner and outer wings of the wing, and rock bones, and mastoid processes of the middle ear can be clearly displayed. The inner auditory canal also often shows better. Nasopharyngeal carcinoma often has skull base bone destruction.