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Parietal Foramina
A parietal foramen is an opening in the skull for the parietal emissary vein, which drains into the superior sagittal sinus. Occasionally, a small branch of the occipital artery can also pass through it. It is located at the back part of the parietal bone, close to the upper or sagittal border. It is not always present, and its size varies considerably. Parietal foramina tend to be symmetrical, with the same number on each side. See also * Foramina of skull This article lists foramina that occur in the human body. __TOC__ Skull The human skull has numerous openings (foramina), through which cranial nerves, arteries, veins, and other structures pass. These foramina vary in size and number, with ... References External links Foramina of the skull {{musculoskeletal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parietal Bone
The parietal bones () are two bones in the skull which, when joined at a fibrous joint, form the sides and roof of the 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 ig. 1is 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. At the back part an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skeletal System
A skeleton is the structural frame that supports the body of an animal. There are several types of skeletons, including the exoskeleton, which is the stable outer shell of an organism, the endoskeleton, which forms the support structure inside the body, and the hydroskeleton, a flexible internal skeleton supported by fluid pressure. Vertebrates are animals with a vertebral column, and their skeletons are typically composed of bone and cartilage. Invertebrates are animals that lack a vertebral column. The skeletons of invertebrates vary, including hard exoskeleton shells, plated endoskeletons, or spicules. Cartilage is a rigid connective tissue that is found in the skeletal systems of vertebrates and invertebrates. Etymology The term ''skeleton'' comes . ''Sceleton'' is an archaic form of the word. Classification Skeletons can be defined by several attributes. Solid skeletons consist of hard substances, such as bone, cartilage, or cuticle. These can be further divided by lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emissary Vein
The emissary veins connect the extracranial venous system with the intracranial venous sinuses. They connect the veins outside the cranium to the venous sinuses inside the cranium. They drain from the scalp, through the skull, into the larger meningeal veins and dural venous sinuses. Emissary veins have an important role in selective cooling of the head. They also serve as routes where infections are carried into the cranial cavity from the extracranial veins to the intracranial veins. There are several types of emissary veins including posterior condyloid, mastoid, occipital and parietal emissary vein. Structure There are also emissary veins passing through the foramen ovale, jugular foramen, foramen lacerum, and hypoglossal canal. Function Because the emissary veins are valveless, they are an important part in selective brain cooling through bidirectional flow of cooler blood from the evaporating surface of the head. In general, blood flow is from external to internal but ... [...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 area along the attached margin of the falx cerebri. It allows blood to drain from the lateral aspects of anterior cerebral hemispheres to the confluence of sinuses. Cerebrospinal fluid drains through arachnoid granulations into the superior sagittal sinus and is returned to venous circulation. Structure Commencing at the foramen cecum, through which it receives emissary veins from the nasal cavity, it runs from anterior to posterior, grooving the inner surface of the frontal, 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 drains into the confluence of sinuses and deviates to either side (usually the right). At this point it is continued as the corresponding transverse sinus. The superior sagittal sinus is usually divided into three parts: anteri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Occipital Artery
The occipital artery arises from the external carotid artery opposite the facial artery. Its path is below the posterior belly of digastric to the occipital region. This artery supplies blood to the back of the scalp and sternocleidomastoid muscles, and deep muscles in the back and neck. Structure At its origin, it is covered by the posterior belly of the digastricus and the stylohyoideus, and the hypoglossal nerve winds around it from behind forward; higher up, it crosses the internal carotid artery, the internal jugular vein, and the vagus and accessory nerves. It next ascends to the interval between the transverse process of the atlas and the mastoid process of the temporal bone, and passes horizontally backward, grooving the surface of the latter bone, being covered by the sternocleidomastoideus, splenius capitis, longissimus capitis, and digastricus, and resting upon the rectus capitis lateralis, the obliquus superior, and semispinalis capitis. It then changes its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foramina Of Skull
This article lists foramina that occur in the human body. __TOC__ Skull The human skull has numerous openings (foramina), through which cranial nerves, arteries, veins, and other structures pass. These foramina vary in size and number, with age. Gray193.png , Base of the skull, upper surface Gray187.png , Base of the skull, inferior surface, attachment of muscles marked in red Spine Within the vertebral column (spine) of vertebrates, including the human spine, each bone has an opening at both its top and bottom to allow nerves, arteries, veins, etc. to pass through. Other * Apical foramen, the opening at the tip of the root of a tooth * Foramen ovale (heart), an opening between the venous and arterial sides of the fetal heart * Foramen transversarium, one of a pair of openings in each cervical vertebra, in which the vertebral artery travels * Greater sciatic foramen, a major foramen of the pelvis * Interventricular foramen, channels connecting ventricles in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
