The facial canal is a bony canal found in the temporal bone of the skull. It is a small, tubular structure that runs through the temporal bone, passing through the petrous part of the temporal bone and the zygomatic bone. It is an important structure in the anatomy of the head and neck, as it contains several important structures including the facial nerve, the chorda tympani nerve, and the stylomastoid artery.
Structure
The facial canal is a small, bony canal that is located within the temporal bone of the skull. It is roughly oval in shape, with a length of about 35mm and a width of about 10mm. The facial canal has three main divisions: the petrous portion, the labyrinthine portion, and the stylomastoid portion.
The petrous portion is the first division of the facial canal, and it is located within the petrous part of the temporal bone. This portion of the facial canal is the narrowest and most rigid part of the canal, and it is responsible for protecting the facial nerve as it passes through the temporal bone.
The labyrinthine portion is the second division of the facial canal, and it is located within the labyrinthine part of the temporal bone. This portion of the facial canal is much wider and more flexible than the petrous portion, and it is responsible for protecting the chorda tympani nerve as it passes through the temporal bone.
The stylomastoid portion is the final division of the facial canal, and it is located within the stylomastoid foramen of the temporal bone. This portion of the facial canal is the widest and most flexible part of the canal, and it is responsible for transmitting the stylomastoid artery to the external auditory meatus.
Location
The facial canal is located within the temporal bone of the skull, which is a large, irregular bone located on the side of the head. The temporal bone is divided into four main parts: the squamous part, the tympanic part, the petrous part, and the styloid process.
The squamous part is the largest and most superficial part of the temporal bone, and it forms the lateral and superior aspects of the temporal bone. The tympanic part is located deep to the squamous part, and it forms the posterior and inferior aspects of the temporal bone. The petrous part is located deep to the tympanic part, and it forms the anterior and superior aspects of the temporal bone. The styloid process is a small, pointed projection that extends inferiorly from the base of the petrous part.
The facial canal is located within the petrous part of the temporal bone, and it passes through the petrous part, the labyrinthine part, and the stylomastoid foramen to reach the external auditory meatus.
Function
The facial canal has several important functions in the anatomy of the head and neck. Its primary function is to protect and transmit several important structures that pass through the temporal bone.
The facial nerve is the most important structure contained within the facial canal, and it is responsible for controlling the muscles of the face and head. The facial nerve passes through the petrous portion of the facial canal, and it is responsible for transmitting sensory and motor impulses to the face and head.
The chorda tympani nerve is another important structure contained within the facial canal, and it is responsible for transmitting taste sensations from the anterior two-thirds of the tongue to the brain. The chorda tympani nerve passes through the labyrinthine portion of the facial canal, and it is also responsible for transmitting parasympathetic innervation to the submandibular and sublingual salivary glands.
The stylomastoid artery is a small artery that supplies blood to the posterior part of the ear and the base of the skull. The stylomastoid artery passes through the stylomastoid portion of the facial canal, and it is responsible for supplying blood to these structures.
