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Groove For Sigmoid Sinus
Groove for Sigmoid Sinus is a groove in the posterior cranial fossa. It starts at lateral parts of occipital bone, curves around jugular process, and ends at posterior inferior angle of parietal bone. After that, groove for sigmoid sinus continues as groove for transverse sinus. See also * Sigmoid sinus The sigmoid sinuses (sigma- or s-shaped hollow curve), also known as the , are venous sinuses within the skull that receive blood from posterior dural venous sinus veins. Structure The sigmoid sinus is a dural venous sinus situated within the du ... References External links * http://ect.downstate.edu/courseware/haonline/labs/l22/os0808.htm Skull {{musculoskeletal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Cranial Fossa
The posterior cranial fossa is part of the cranial cavity, located between the foramen magnum and tentorium cerebelli. It contains the brainstem and cerebellum. This is the most inferior of the fossae. It houses the cerebellum, medulla and pons. Anteriorly it extends to the apex of the petrous temporal. Posteriorly it is enclosed by the occipital bone. Laterally portions of the squamous temporal and mastoid part of the temporal bone form its walls. Features Foramen magnum The most conspicuous, large opening in the floor of the fossa. It transmits the medulla, the ascending portions of the spinal accessory nerve (XI), and the vertebral arteries. Internal acoustic meatus Lies in the anterior wall of the posterior cranial fossa. It transmits the facial (VII) and vestibulocochlear (VIII) cranial nerves into a canal in the petrous temporal bone. Jugular foramen Lies between the inferior edge of the petrous temporal bone and the adjacent occipital bone and transmits the internal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Cranial Fossa
The posterior cranial fossa is part of the cranial cavity, located between the foramen magnum and tentorium cerebelli. It contains the brainstem and cerebellum. This is the most inferior of the fossae. It houses the cerebellum, medulla and pons. Anteriorly it extends to the apex of the petrous temporal. Posteriorly it is enclosed by the occipital bone. Laterally portions of the squamous temporal and mastoid part of the temporal bone form its walls. Features Foramen magnum The most conspicuous, large opening in the floor of the fossa. It transmits the medulla, the ascending portions of the spinal accessory nerve (XI), and the vertebral arteries. Internal acoustic meatus Lies in the anterior wall of the posterior cranial fossa. It transmits the facial (VII) and vestibulocochlear (VIII) cranial nerves into a canal in the petrous temporal bone. Jugular foramen Lies between the inferior edge of the petrous temporal bone and the adjacent occipital bone and transmits the internal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lateral Parts Of Occipital Bone
The lateral parts of the occipital bone (also called the exoccipitals) are situated at the sides of the foramen magnum; on their under surfaces are the condyles for articulation with the superior facets of the atlas. Description The condyles are oval or reniform (kidney-shaped) in shape, and their anterior extremities, directed forward and medialward, are closer together than their posterior, and encroach on the basilar portion of the bone; the posterior extremities extend back to the level of the middle of the foramen magnum. The articular surfaces of the condyles are convex from before backward and from side to side, and look downward and lateralward. To their margins are attached the capsules of the atlantoöccipital articulations, and on the medial side of each is a rough impression or tubercle for the alar ligament. At the base of either condyle the bone is tunnelled by a short canal, the hypoglossal canal (anterior condyloid foramen). This begins on the cranial surface o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jugular Process
The jugular process is a quadrilateral or triangular bony plate projecting lateralward from the posterior half of the occipital condyle; it is a part of the lateral part of the occipital bone. The jugular process is excavated in front by the jugular notch of occipital bone (which forms the posterior part of the jugular foramen). The posterolateral side of the jugular formanen is divided from the anteromedial side by the intrajugular process of occipital bone. The jugular process serves as the insertion of the rectus capitis lateralis The rectus capitis lateralis, a short, flat muscle, arises from the upper surface of the transverse process of the atlas, and is inserted into the under surface of the jugular process of the occipital bone. Additional images File:Rectus capitis .... References External links * Bones of the head and neck {{musculoskeletal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parietal Bone
The parietal bones () are two bones in the Human skull, skull which, when joined at a fibrous joint, form the sides and roof of the Human skull, cranium. In humans, each bone is roughly quadrilateral in form, and has two surfaces, four borders, and four angles. It is named from the Latin ''paries'' (''-ietis''), wall. Surfaces External The external surface [Fig. 1] is convex, smooth, and marked near the center by an eminence, the parietal eminence (''tuber parietale''), which indicates the point where ossification commenced. Crossing the middle of the bone in an arched direction are two curved lines, the superior and inferior temporal lines; the former gives attachment to the temporal fascia, and the latter indicates the upper limit of the muscular origin of the temporal muscle. Above these lines the bone is covered by a tough layer of fibrous tissue – the epicranial aponeurosis; below them it forms part of the temporal fossa, and affords attachment to the temporal muscle. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Groove For Transverse Sinus
The groove for transverse sinus is a groove which runs along the internal surface of the occipital bone, running laterally between the superior and inferior fossae of the cruciform eminence. The transverse sinuses travel along this groove. A small or absent bony groove in the occiput in conjunction with the compressible nature of the transverse sinus makes this structure vulnerable to tapering with increased ICP. Additional images File:Occipital bone 4.jpg, Base of the skull. Upper surface. Groove for transverse sinus labelled at bottom. File:Gray570.png, Base of the skull. Upper surface. Transverse sinuses are drawn at bottom. See also * Internal occipital protuberance * Occipital bone * Transverse sinus The transverse sinuses (left and right lateral sinuses), within the human head, are two areas beneath the brain which allow blood to drain from the back of the head. They run laterally in a groove along the interior surface of the occipital bone. ... References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sigmoid Sinus
The sigmoid sinuses (sigma- or s-shaped hollow curve), also known as the , are venous sinuses within the skull that receive blood from posterior dural venous sinus veins. Structure The sigmoid sinus is a dural venous sinus situated within the dura mater. The sigmoid sinus receives blood from the transverse sinuses, which track the posterior wall of the cranial cavity, travels inferiorly along the parietal bone, temporal bone and occipital bone, and converges with the inferior petrosal sinuses to form the internal jugular vein. Each sigmoid sinus begins beneath the temporal bone and follows a tortuous course to the jugular foramen, at which point the sinus becomes continuous with the internal jugular vein. Function The sigmoid sinus receives blood from the transverse sinuses, which receive blood from the posterior aspect of the skull. Along its course, the sigmoid sinus also receives blood from the cerebral veins, cerebellar veins, diploic veins, and emissary veins. See als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
