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Squamous Part Of Occipital Bone
The squamous part of occipital bone is situated above and behind the foramen magnum, and is curved from above downward and from side to side. External surface The external surface is convex and presents midway between the summit of the bone and the foramen magnum a prominence, the external occipital protuberance and inion. Extending lateralward from this on either side are two curved lines, one a little above the other. The upper, often faintly marked, is named the highest nuchal line, and to it the epicranial aponeurosis is attached. The lower is termed the superior nuchal line. That area of the squamous part, which lies above the highest nuchal lines is named the occipital plane ''(planum occipitale)'' and is covered by the '' occipitalis muscle''. That below, termed the nuchal plane, is rough and irregular for the attachment of several muscles. From the external occipital protuberance, an often faintly marked ridge or crest, the median nuchal line, descends to the foramen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Skull
The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate. In the human, the skull comprises two prominent parts: the neurocranium and the facial skeleton, which evolved from the first pharyngeal arch. The skull forms the frontmost portion of the axial skeleton and is a product of cephalization and vesicular enlargement of the brain, with several special senses structures such as the eyes, ears, nose, tongue and, in fish, specialized tactile organs such as barbels near the mouth. The skull is composed of three types of bone: cranial bones, facial bones and ossicles, which is made up of a number of fused flat and irregular bones. The cranial bones are joined at firm fibrous junctions called sutures and contains many foramina, fossae, processes, and sinuses. In zoology, the openings in the skull are called fenestrae, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Atlantooccipital Membrane
The posterior atlantooccipital membrane (posterior atlantooccipital ligament) is a broad but thin membrane extending between the posterior margin of the foramen magnum above, and posterior arch of atlas (first cervical vertebra) below. It forms the floor of the suboccipital triangle. The membrane helps limit excessive movement of the atlanto-occipital joints. Anatomy Attachments The superior attachment of the membrane at the posterior margin of the foramen magnum, and its inferior attachment is at the superior margin of the posterior arch of atlas (cervical vertebra C1). The membrane additionally attaches posteriorly (by a soft tissue bridge which may contain muscle or tendon fibres) to the recti capitis posteriores minores mucles, and anteriorly to the dura mater. Innervation The membrane is innervated by the spinal nerve C1. Relations At either lateral extremity, the membrane is pierced by the vertebral artery and cervical spinal nerve C1. The free border of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transverse Sinuses
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. They drain from the confluence of sinuses (by the internal occipital protuberance) to the sigmoid sinuses, which ultimately connect to the internal jugular vein. ''See diagram (at right)'': labeled under the brain as "" (for Latin: ''sinus transversus'' https://www.ncbi.nlm.nih.gov/books/NBK482257] Structure The transverse sinuses are of large size and begin at the internal occipital protuberance; one, generally the right, being the direct continuation of the |
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 for transverse sinus, groove along the interior ... References E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebellar Vermis
The cerebellar vermis (from Latin ''vermis,'' "worm") is located in the medial, cortico-nuclear zone of the cerebellum, which is in the posterior cranial fossa, posterior fossa of the cranium. The primary fissure in the vermis curves ventrolaterally to the anatomical terms of location, superior surface of the cerebellum, dividing it into anterior and posterior (anatomy), posterior lobe (anatomy), lobes. Functionally, the vermis is associated with bodily Neutral spine, posture and Motion (physics), locomotion. The vermis is included within the Anatomy of the cerebellum#Phylogenetic and functional divisions, spinocerebellum and receives somatic sensory input from the head and proximal body parts via spinal cord, ascending spinal pathways. The cerebellum develops in a rostro-caudal manner, with Anatomical terms of location#Directional terms, rostral regions in the midline giving rise to the vermis, and Caudal (anatomical term), caudal regions developing into the cerebellar hemisphere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Falx Cerebelli
The falx cerebelli is a small sickle-shaped fold of dura mater projecting forwards into the posterior cerebellar notch as well as projecting into the vallecula of the cerebellum between the two cerebellar hemispheres. The name comes from two Latin words: ''falx'', meaning "curved blade or scythe", and ''cerebellum'', meaning "little brain". Anatomy The falx cerebelli is a small midline fold of dura mater projecting anterior-ward from the skull and into the space between the cerebellar hemispheres. It generally measures between 2.8 and 4.5 cm in length, and approximately 1–2 mm in thickness. Attachments Superiorly, it (with its upwardly directed base) attaches at the midline to the posterior portion of the inferior surface of the tentorium cerebelli. Posteriorly, it attaches to the internal occipital crest; the inferior-most extremity of its posterior attachment frequently divides into two small folds that terminate at either side of the foramen magnum. An ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Occipital Crest
In the occipital bone, the lower division of the cruciate eminence is prominent, and is named the internal occipital crest; it bifurcates near the foramen magnum and gives attachment to the falx cerebelli; in the attached margin of this falx is the occipital sinus, which is sometimes duplicated. In the upper part of the internal occipital crest, a small depression is sometimes distinguishable; it is termed the vermian fossa since it is occupied by part of the cerebellar vermis of the cerebellum. Additional images File:Internal occipital crest - animation.gif, Position of internal occipital crest (shown in red). Animation. File:Internal occipital crest - superior view.png, Base of the skull. Internal occipital crest shown in red. File:Gray193 Internal occipital crest.png , Base of the skull. Upper surface. (Internal occipital crest visible below foramen magnum The foramen magnum () is a large, oval-shaped opening in the occipital bone of the skull. It is one of the several ova ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Falx Cerebri
The falx cerebri (also known as the cerebral falx) is a large, crescent-shaped fold of dura mater that descends vertically into the longitudinal fissure to separate the cerebral hemispheres.Saladin K. "Anatomy & Physiology: The Unity of Form and Function. New York: McGraw Hill, 2014. Print. pp 512, 770-773 It supports the dural sinuses that provide venous and CSF drainage from the brain. It is attached to the crista galli anteriorly, and blends with the tentorium cerebelli posteriorly. The falx cerebri is often subject to age-related calcification, and a site of falcine meningiomas. The falx cerebri is named for its sickle-like shape. Anatomy The falx cerebri is a strong, crescent-shaped sheet of dura mater lying in the sagittal plane between the two cerebral hemispheres. It is one of four dural partitions of the brain along with the falx cerebelli, tentorium cerebelli, and diaphragma sellae; it is formed through invagination of the dura mater into the longitudina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superior Sagittal Sinus
The superior sagittal sinus (also known as the superior longitudinal sinus), within the human head, is an unpaired dural venous sinus lying along the attached margin of the falx cerebri. It allows blood to drain from the lateral aspects of the anterior cerebral hemispheres to the confluence of sinuses. Cerebrospinal fluid drains through arachnoid granulations into the superior sagittal sinus and is returned to the venous circulation. Structure It is triangular in section. It is narrower anteriorly, and gradually increases in size as it passes posterior-ward. It commences at the foramen cecum, through which it receives emissary veins from the nasal cavity. It passes posterior-ward along its entire course. It is accommodated within a groove which runs across the inner surface of the frontal bone, the adjacent margins of the two parietal lobes, and the superior division of the cruciate eminence of the occipital lobe. Near the internal occipital protuberance, it deviates to e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sagittal Sulcus
The sagittal sulcus is a midline groove that runs across the internal surfaces of part of the squamous part of the frontal bone, the parietal bones, and part of the occipital bones. The sagittal sulcus accommodates the superior sagittal sinus. The falx cerebri attaches to the edge of the sagittal sulcus on either side. On the inferior portion of the squamous part of the frontal bone, the edges of the sagittal sinus converge to form a single midline ridge, the frontal crest The frontal crest is a ridge on the internal surface of the squamous part of the frontal bone The squamous part of the frontal bone is the superior (approximately two thirds) portion when viewed in standard anatomical orientation. There are two ... (which also gives attachment to the falx cerebri). References Bones of the head and neck {{musculoskeletal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Occipital Protuberance
Along the internal surface of the occipital bone, at the point of intersection of the four divisions of the cruciform eminence, is the internal occipital protuberance. Running transversely on either side is a groove for the transverse sinus. Additional images See also * External occipital protuberance External may refer to: * Externality, in economics, the cost or benefit that affects a party who did not choose to incur that cost or benefit * Externals, a fictional group of X-Men antagonists See also * * Internal (other) {{disa ... References External links * Diagram at uni-mainz.de Bones of the head and neck {{musculoskeletal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebellum
The cerebellum (: cerebella or cerebellums; Latin for 'little brain') is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as it or even larger. In humans, the cerebellum plays an important role in motor control and cognition, cognitive functions such as attention and language as well as emotion, emotional control such as regulating fear and pleasure responses, but its movement-related functions are the most solidly established. The human cerebellum does not initiate movement, but contributes to motor coordination, coordination, precision, and accurate timing: it receives input from sensory systems of the spinal cord and from other parts of the brain, and integrates these inputs to fine-tune motor activity. Cerebellar damage produces disorders in fine motor skill, fine movement, sense of balance, equilibrium, list of human positions, posture, and motor learning in humans. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
