What is the petrous part of the temporal bone?

The petrous part of the temporal bone (or more simply petrous temporal bone, PTB) forms the part of skull base between the sphenoid and occipital bones.

What are the 3 regions of the temporal bone?

Structure. The temporal bone consists of four parts— the squamous, mastoid, petrous and tympanic parts.

What are the four regions of the temporal bone?

The temporal bones comprise four regions:

• the squamous region, which is the largest.
• the mastoid region.
• the petrous region.
• the tympanic region.

What channel passes through the pyramid of the temporal bone?

The internal acoustic meatus is another canal passing through the petrous part of the temporal bone between the posterior cranial fossa and the external acoustic meatus. Passing through this opening are the facial nerve (CN VII), the vestibulocochlear nerve (CN VIII) and the labyrinthine artery.

Why is it called petrous part of temporal bone?

Petrous comes from the Latin word petrosus, meaning “stone-like, hard”. It is one of the densest bones in the body. The petrous bone is important for studies of ancient DNA from skeletal remains, as it tends to contain extremely well-preserved DNA.

Is styloid process of temporal bone?

The styloid process (SP) consists of two narrow and elongated bony projections of the temporal bone. They are located anteriorly to the stylomastoid foramen on the right and left sides of base of the skull [1].

Does the temporal bone have a sinus?

Explanation: There are four paranasal sinuses in the head: the frontal, maxillary, sphenoid, and ethmoid sinuses. They function in lightening the skull, and creating mucous for the nasal cavity. The temporal bone does not contain a sinus.

Is the temporal bone weak?

The temporal bone is a very thick and hard structure located in the base of the skull. The base of the skull has multiple foramina, as seen in the images below, creating areas of decreased resistance susceptible to traumatic injury.

Is the temporal bone an irregular bone?

Temporal bones. This is a pair of irregular bones located under each of the parietal bones.

How serious is a temporal bone fracture?

In adults and children, temporal bone fractures with otic capsule disruption are severe and more prone to complications (such as facial nerve paralysis, sensorineural hearing loss, conductive hearing loss, CSF otorrhea) and sequelae than are temporal bone fractures with otic capsule sparing.

What is the hardest part of the temporal bone?

The petrous portion is among the most basal elements of the skull and forms part of the endocranium. Petrous comes from the Latin word petrosus, meaning “stone-like, hard”. It is one of the densest bones in the body.

Where is styloid process of temporal bone?

Where is the petrous part of the temporal bone located?

[edit on Wikidata] The petrous part of the temporal bone is pyramid-shaped and is wedged in at the base of the skull between the sphenoid and occipital bones. Directed medially, forward, and a little upward, it presents a base, an apex, three surfaces, and three angles, and houses in its interior, the components of the inner ear.

Where is the apex of the petrous bone located?

The petrous apex is a pyramid-shaped structure that is formed by the medial portions of the temporal bone. It is obliquely positioned within the skull base, with its apex pointing anteromedially and its base located posterolaterally.

Is the middle ear part of the temporal bone?

The middle ear is an air-filled cavity within the petrous portion of the temporal bone that contains the ossicular chain and is bounded by the tympanic membrane laterally, the inner ear structures (surrounded by the otic capsule and the cochlear promontory) medially, the tegmen tympani superiorly, and the jugular wall (floor) inferiorly (Fig 5).

How does Ewing’s sarcoma of the petrous temporal bone affect?

Primary Ewing’s sarcoma of the skull typically respects dural planes and often presents as an expansile mass causing symptoms of increased intracranial pressure. Within the skull, this sarcoma typically affects the frontal and parietal bones, as well as the temporal (squamosa and mastoid), ethmoid, orbital, and maxillary bones.