Search results
Results from the WOW.Com Content Network
The mastoid process serves for the attachment of the sternocleidomastoid, the posterior belly of the digastric muscle, splenius capitis, and longissimus capitis. On the medial side of the process is a deep groove, the mastoid notch, for the attachment of the digastric muscle ; medial to this is a shallow furrow, the occipital groove , which ...
extending backward from the carotid canal is the vaginal process, a sheath-like plate of bone, which divides behind into two laminæ; the lateral lamina is continuous with the tympanic part of the bone, the medial with the lateral margin of the jugular surface; between these laminæ is the styloid process, a sharp spine, about 2.5 cm. in length
They may excavate the mastoid process to its tip, and be separated from the posterior cranial fossa and sigmoid sinus by a mere slip of bone or not at all. They may extend into the squamous part of temporal bone, petrous part of the temporal bone zygomatic process of temporal bone, and - rarely - the jugular process of occipital bone; they may thus come to adjoin many important structures ...
The temporal bone consists of four parts—the squamous, mastoid, petrous and tympanic parts. [1] [2] The squamous part is the largest and most superiorly positioned relative to the rest of the bone. The zygomatic process is a long, arched process projecting from the lower region of the squamous part and it articulates with the zygomatic bone ...
The tympanic part of the temporal bone is a curved plate of bone lying below the squamous part of the temporal bone, in front of the mastoid process, and surrounding the external part of the ear canal. It originates as a separate bone (tympanic bone), which in some mammals stays separate through life.
The mastoid antrum (tympanic antrum, antrum mastoideum, Valsalva's antrum) is an air space in the petrous portion of the temporal bone, communicating posteriorly with the mastoid cells and anteriorly with the epitympanic recess of the middle ear via the aditus to mastoid antrum (entrance to the mastoid antrum). These air spaces function as ...
The mastoid foramen is a hole in the posterior border of the temporal bone of the skull. [1] The opening of the mastoid foramen is an average of 18 mm from the asterion, [2] and around 34 mm from the external auditory meatus. [3] It is typically very narrow. [1] [3] This may be around 2 mm. [3]
The inner surface of the mastoid portion of the temporal bone presents a deep, curved groove, the sigmoid sulcus, which lodges part of the transverse sinus; in it may be seen the opening of the mastoid foramen.