Occipital bone

Lufkin, T., Mark, M., Hart, C. P Dolle, R, LeMeur, M., and Chambon, P. (1992). Homeotic transformation of the occipital bones of the skull by ectopic expression of a homeobox gene. Nature 359 835-841. 

Annular or Aymara. This type resembles a cone directed posteriorly. Usually bandages are employed which are placed across the frontal region and encircle the head, passing across the temporals and the occipital bone. 

Monkeys After induction of anesthesia, monkeys were placed in a Kopf stereotactic head holder, and a linear incision was made from the inion to the spinous process of C2. A burr hole was made in the midline on the occipital bone 2.5 cm below the inion. The dura was opened with a scalpel blade (no. 11) and the edges of the dura were coagulated by bipolar cautery. The infusion... 

Although somites are indistinguishable, most vertebrae exhibit unique morphological characteristics. The anterior-most somites gives rise to the occipital bones, while more posterior somites gives rise to the vertebral column. In the mouse, the vertebral column is normally composed of 7 cervical (C1-C7), 13 thoracic (T1-T13), 6 lumbar (L1-L6), 3 or 4 sacral (S1-S4), and 31 caudal vertebrae. The first cervical vertebra (Cl, or atlas) has thick neural arches, lacks a vertebral body, and exhibits a ventrally located tubercle, the anterior arch of the atlas (AAA). The neural arches of C2, although not as broad as those of Cl, are thicker than the more posterior cervical vertebrae. C2 also possesses two vertebral bodies, the second of which... 

The brain resides within the cranial cavity. The bony roof and sides of the cranial vault make up the calvaria, which is composed of frontal, temporal and parietal bones and a small portion of the occipital bone. The floor of the cranial vault is divided into three depressions or fossae the anterior fossa extends from the region superior to the orbits and nasal cavity caudaUy as far as the posterior margin of the lesser wing of the sphenoid the middle fossa occupies the region between the lesser wing of the sphenoid and the anterior border of the petrous portion of the temporal bone and the posterior fossa, is underlain by the remainder of the temporal bones and the occipital bone. 

Osteoblastic cells were obtained from new bom rat calvariae, isolated and sub-cultured as described by Has awa et al. [17] and Chehroudi et al. [18]. Frontal, parietal and occipital bone were dissected, rinsed in phosphate-buffered saline (PBS, Fluka Chemicals, Buchs, Switzerland), placed in Dulbecco s modified Eagles medium (a-DMEM, Invitrogen, Basel, Switzerland), supplemented with 1% antibiotics (Penstrep, Invitrogen, Basel, Switzerland) and 10% foetal bovine serum (Invitrogen, Basel, Switzerland). The minced tissue was digested with a mixture of clostridial collagenase and trypsin (both from Sigma-Aldrich, Buchs, Switzerland) and then placed in tissue-culture flasks. 

For lentivirus injection into the cerebellum, mice are anesthetized and fixed to the stereotaxic instrument as described above. A small cranial window is formed on the occipital bone with an electrical drill (for adult mice) or a 27-G needle (for pups), and the surface of cerebellar lobules VI-VII is exposed. A glass pipette filled with lentivirus solution is then inserted into the cerebellum. Two weeks later, mice are transcardially perfused with 4 % PFA. 

The posterior wall of the pharynx takes its upper origin from the pharyngeal tubercle of the occipital bone and is continued forward to the medial pterygoid plate of the sphenoid. Below it suddenly narrows at the level of C 5-6 as it becomes the upper part of the oesophagus. The transoral approach therefore is suitable to gain access to the clivus as well as to the area of the uppermost cervical bodies. 

Longus capitis which originates from the transverse processes of the lower cervical bodies and inserts into the basilar part of the occipital bone. It is also a flexor of the head. 

In cases of atlanto-axial dislocation operated by the transoral route stabilisation of the spine is a crucial point. There are methods to achieve this fixation anteriorly. De Rougemount et al. (1966) placed a bone graft anteriorly from the ventral rim of the occipital bone to the level of the body of the axis. Thompson (1970) proposed the same fixation with bone chips after denuding the anterior surface of the bony structures. Estridge and... 

Fig. 13. Case no. 11. Pre-operative AP tomogram demonstrates the elevated foraminal rim of the occipital bone...

Fig. 28. X-ray control 2V2 years post-operatively shows re-ossification in the C2 body. The posterior internal fixation using wires can be seen. The screws shows where the bilateral bone grafts have been fixed to the occipital bone...

Named for the bones of the cranium under which they lie, the lobes are conspicuously defined by prominent sulci of the cortex, which have a relatively constant position in human brains. Each lobe is specialized for different activities (see Figure 6.3). Located in the anterior portions of the hemispheres, the frontal lobes are responsible for voluntary motor activity, speaking ability, and higher intellectual activities. The parietal lobes, which are posterior to the frontal lobes, process and integrate sensory information. The occipital lobes, located in the posterior-most aspects of the cerebrum, process visual information, and the temporal lobes, located laterally, process auditory information. 

The cerebral cortex is conventionally subdivided into four main regions that may be delineated by the sulci, or large clefts, termed the frontal, temporal, parietal and occipital lobes. These names are derived from the bones of the skull which overlay them. Each lobe may be further subdivided according to its cellular structure and composition. Thus Brodmarm has divided the cortex into approximately 50 discrete areas according to the specific cellular structure and function. For example, electrical stimulation of the strip of cerebral cortex in front of the central sulcus (see Figure 1.3) is responsible for motor commands to the muscles. This is termed the primary motor cortex and can be further subdivided according to which muscles are controlled in different parts of the body. 

Skull Pre-maxillae, nasals, frontals, parietals, interparietal, occipitals (supraoccipital, occipital condyles, basioccipital), zygomatics, squamosals, lacrimals, tympanic bullae, mandibles, hyoid, palatine bone, vomer, presphenoid, basisphenoid, maxillae Figs. 1, 2, 3, and 4. 

If the hominoids became aquatic waders, they seemed to return to land about three million years ago. Researchers find fossils of Homo Habilus at this time. The trail then leads confidently on once more to Homo Erectus and to the black, hairy African Neanderthal called Homo Sapien. He was characterized by an Occipital Bun or Skull Bone Ridge. 

The divisions of the cranial central nervous system include the cerebral hemispheres, the diencephalon (thalamus and hypothalamus), the brainstem (midbrain, pons and medulla oblongata) and the cerebellum (Fig. 1.2). Each cerebral hemisphere occupies one half of the cranial vault and can be subdivided into four lobes (frontal, parietal, temporal, occipital), the insula and the limbic lobe. The first four lobes are named for the cranial bones that overlie them. With respect to the floor of the cranial cavity, the frontal lobes lie in the anterior cranial fossa the brainstem and cerebellum occupy the posterior cranial fossa the remaining structures are found either in the middle fossa or within the portion of the cranial vault above the tentorium cerebelli. The insula is covered by the temporal lobe and is not observable unless the temporal lobe is retracted. The hmbic system is a continuous interior... 

Blood and bone lead levels had significantly negative correlation with NAA tCr, Cho tCr ratios in frontal, occipital lobes compatible... 

Fig. 25.7a,b. Coronal volume-rendered multi-detector rowCT images in a patient with a high speed motorcycle accident to the upper cervical spine and the occipito-cervical junction, a Volume-rendering reconstruction with a low bone opacity shows a widening of the atlanto-axial junction as defined by a subluxation (arrows), which could not be detected in the axial source images, b Oblique coronal reformatted volumerendering reconstruction shows an additional fracture of the occipital condyles (arrowheads)... 

Occipital Horn syndrome Connective tissue, bone fibroblasts (for diagnosis), intestine, nervous system Xql3.3 304150... 

Venous sinuses drain 95% of blood from the cranium via the Internal jugular vein. It is of crucial Importance that there Is proper relation and motion between the occipital and temporal bones, which comprise the jugular foramen, to have unimpeded venous drainage. The remaining 5% of venous blood drains via facial veins and the external jugular vein. 

One way to perform the CV-4 is for the operator to place her thenar eminences on the occipital squama, below the superior nuchal line. The hands must not be on the temporal bone or the occipitomastoid [OM) suture, because this will create dysfunctions. The OM suture should be located before the hands are placed to avoid its compression. Fingers may then be either overlapped or interlaced to cradle the occiput. It is crucial to remember that the intent of this technique is to affect the fluid of the fourth ventricle and not to compress the associated bones and meninges. 

Findings observed on osteopathic examination were compression of the occipital condyles bilaterally (the left side greater than right], left parietal bone externally rotated, right medial pterygoid muscle spasm, and an anterior sacral base. No bossing ofthe frontal and parietal bones was noted and there was no overlapping of sutures present. 

The placoderm endoeranium is composed of two units (Figure 13.1). The posterior unit represents the main endocranial body which extends from the ethmoid to the occipital margins. As mentioned above, this bone does not show any trace of ventral or otico-occipital fissure like those present in osteichthyans and in some chondrichthyans Pucapampella, Maisey, this volume). The anterior unit is composed of the paired nasal capsules which are always enclosed in an ossification including the endoskeleton and its dermal cover. 

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