Academic literature on the topic 'Osso temporal/anatomia'

Chapter 1 considers the circumstances underpinning Pope Benedict XIV’s patronage of anatomy and anatomical modelling in Bologna and antiquarian display in Rome. It situates the pope’s support of anatomy in the wider context of his religious pursuits as an assessor of sanctity who saw in anatomy a powerful tool for identifying signs of holy embodiment. In particular, the chapter explores Lambertini’s patronage of anatomical modelling and practice in light of the role he attributed to anatomical knowledge in his major work on canonization, his De servorum Dei beatificatione et canonizatione beat

Recent advances in palaeoclimatological and meteorological research, combined with new radiocarbon data from western Anatolia and southeast Europe, lead us to formulate a new hypothesis for the temporal and spatial dispersal of Neolithic lifeways from their core areas of genesis. The new hypothesis, which we term the Abrupt Climate Change (ACC) Neolithization Model, incorporates a number of insights from modern vulnerability theory. We focus here on the Late Neolithic (Anatolian terminology), which is followed in the Balkans by the Early Neolithic (European terminology). From high-resolution 1

Clinical experience and multiple prospective studies, such as the Collaborative Normal Tension Glaucoma Study and the Los Angeles Latino Eye Study, have demonstrated that the diagnosis of glaucoma is more complex than identifying elevated intraocular pressure. As a result, increased emphasis has been placed on measurements of the structural and functional abnormalities caused by glaucoma. The refinement and adoption of imaging technologies assist the clinician in the detection of glaucomatous damage and, increasingly, in identifying the progression of structural damage. Because visual field defects in glaucoma patients occur in patterns that correspond to the anatomy of the nerve fiber layer of the retina and its projections to the optic nerve, visual functional tests become a link between structural damage and functional vision loss. The identification of glaucomatous damage and management of glaucoma require appropriate, sequential measurements and interpretation of the visual field. Glaucomatous visual field defects usually are of the nerve fiber bundle type, corresponding to the anatomic arrangement of the retinal nerve fiber layer. It is helpful to consider the division of the nasal and temporal retina as the fovea, not the optic nerve head, because this is the location that determines the center of the visual field. The ganglion cell axon bundles that emanate from the nasal side of the retina generally approach the optic nerve head in a radial fashion. The majority of these fibers enter the nasal half of the optic disc, but fibers that represent the nasal half of the macula form the papillomacular bundle to enter the temporal-most aspect of the optic nerve. In contrast, the temporal retinal fibers, with respect to fixation, arc around the macula to enter the superotemporal and inferotemporal portions of the optic disc. The origin of these arcuate temporal retinal fibers strictly respects the horizontal retinal raphe, temporal to the fovea. As a consequence of this superior-inferior segregation of the temporal retinal fibers, lesions that affect the superotemporal and inferotemporal poles of the optic disc, such as glaucoma, tend to cause arcuateshaped visual field defects extending from the blind spot toward the nasal horizontal meridian.

In most presentations of associated human fossil remains, the cranium and the mandible are discussed separately, as though they represent separate entities of human anatomy. However, in a paleobiological assessment of the Sunghir human remains, especially for the associated skeletons of Sunghir 1 to 3, it is more relevant to consider them in terms of the two primary functional units of the head, the neurocranium and the facial skeleton. The former includes skeletal elements directly relating to the brain, the special senses contained within the temporal bone, the mandibular articulation, and the muscular attachments on the external portions of the posterior and lateral cranium. The first two aspects are principally neurological, and they can be accessed only to a limited extent given the availability of radiographs of the Sunghir crania but not CT scans. The last two aspects relate to features that would best be considered in the context of the cervical region (the nuchal muscle attachment area) and mastication (the temporomandibular joint and the cranial attachments for temporalis and deep masseter). However, since the nuchal region and the temporomandibular joint are intimately related to more strictly neurocranial aspects of the cranium, they are discussed here, but then the latter is referred to with respect to the facial skeleton. In addition, individual bones, and especially the frontal, ethmoid, and sphenoid bones, form an interface between the neurocranial cavity and the facial skeleton. Their various portions, as they relate to one or the other of these anatomical spheres, are discussed separately. As detailed in chapter 4, there are four largely complete neurocrania from Sunghir. The Sunghir 1 to 3 neurocrania are largely present, but they have sustained variable degrees of in situ distortion and restoration. The Sunghir 5 one was extensively reassembled with generous applications of wax, but most of it appears to be present and in its correct positions. The Sunghir 1 neurocranium is largely complete, with only minor restoration of missing portions.

Numerous oculoplastic surgical procedures are performed on the forehead, eyebrows, eyelids, and canthi. An understanding of the anatomy of these structures, as well as of the nearby temporal artery and facial nerve, is essential for the surgeon working in this region. In this chapter, the surface anatomy is described first, followed by a more detailed description of the tissue beneath. The skin of the forehead and cranium, or the “scalp,” is traditionally considered as five layers (Fig. 1-1): skin, subcutaneous tissue, galea aponeurosis, loose areolar tissue, and periosteum. These layers are present consistently throughout the head, with some slight modifications in certain areas (e.g., the brow area). These layers can be easily remembered with the mnemonic “SCALP” (S = skin, C = subcutaneous tissue, A = galea aponeurotica, L = loose areolar tissue, P = pericranium). The skin of the forehead and temporal region is usually relatively thick and rich in sebaceous glands. However, in some elderly individuals the skin of the temporal forehead can be quite thin and consequently requires a greater degree of care during surgical procedures (e.g., endobrow lift ) and resurfacing (e.g., laser or chemical). Although the eyebrows are technically part of the scalp rather than of the eyelids, they have important functional and surgical relationships to the lids. The eyebrows lie at the junction between the upper eyelids and the forehead. They lie over each superior orbital rim, are separated by the glabella, and are formed by thick, strong, skin-bearing hairs. The underlying muscle fibers, with their cutaneous insertions, move the brows freely over a suborbicularis fat pad adjacent to the underlying periosteum. Each brow has a head, a body, and a tail. The head lies between the supraorbital ridge and the orbital margin, overlying the frontal sinus. The medial brow hairs are almost vertical; the body of the brow follows the supraorbital margin and has hair in a more horizontal direction.

It is essential that dental students and practitioners understand the structure and function of the temporomandibular joints and the muscles of mastication and other muscle groups that move them. The infratemporal fossa and pterygopalatine fossa are deep to the mandible and its related muscles; many of the nerves and blood vessels supplying the structures of the mouth run through or close to these areas, therefore, knowledge of the anatomy of these regions and their contents is essential for understanding the dental region. The temporomandibular joints (TMJ) are the only freely movable articulations in the skull together with the joints between the ossicles of the middle ear; they are all synovial joints. The muscles of mastication move the TMJ and the suprahyoid and infrahyoid muscles also play a significant role in jaw movements. The articular surfaces of the squamous temporal bone and of the condylar head (condyle) of the mandible form each temporomandibular joint. These surfaces have been briefly described in Chapter 22 on the skull and Figure 24.1A indicates their shape. The concave mandibular fossa is the posterior articulating surface of each squamous temporal bone and houses the mandibular condyle at rest. The condyle is translated forwards on to the convex articular eminence anterior to the mandibular fossa during jaw movements. The articular surfaces of temporomandibular joints are atypical; they covered by fibrocartilage (mostly collagen with some chondrocytes) instead of hyaline cartilage found in most other synovial joints. Figures 24.1B and 24.1C show the capsule and ligaments associated with the TMJ. The tough, fibrous capsule is attached above to the anterior lip of the squamotympanic fissure and to the squamous bone around the margin of the upper articular surface and below to the neck of the mandible a short distance below the limit of the lower articular surface. The capsule is slack between the articular disc and the squamous bone, but much tighter between the disc and the neck of the mandible. Part of the lateral pterygoid muscle is inserted into the anterior surface of the capsule. As in other synovial joints, the non-load-bearing internal surfaces of the joint are covered with synovial membrane.

Frontotemporal dementia (FTD) is a family of neurodegenerative diseases and syndromes that most commonly involve the frontal and temporal lobes, producing dramatic alterations of personality, behavior, language, and other cognitive abilities (McKhann et al., 2001). Age of onset tends to be younger than in Alzheimer’s disease (AD), with most patients becoming symptomatic in the sixth decade of life. Although population-based epidemiologic studies of FTD have found a prevalence of approximately 5–10 per 100,000 in patients 50 years of age and older, autopsy-based case series have found that approximately 5% to15% of people with dementia have FTD, a discrepancy suggesting that many cases go undiagnosed during life (Rosso et al., 2003). Recent advances in clinicopathologic correlation have revealed that a number of neurologic conditions previously conceived of as independent disease entities such as progressive supranuclear palsy (PSP), corticobasilar degeneration (CBD), and hippocampal sclerosis dementia are in many cases better classified in the FTD family (McKhann et al., 2001; Blass et al., 2004). Many patients with FTD develop other neurologic syndromes as well, including parkinsonism and amyotrophic lateral sclerosis (ALS). FTD is actually a group of clinical syndromes with overlapping neuropathologies. The clinical expression of the disease relates primarily to the anatomic location of disease involvement rather than the neuropathologic subtype; there are many such subtypes. Clinical variants are most distinct early in the disease course, when the degree of anatomic involvement may be limited to discrete regions. As the disease spreads through the brain, many patients have symptoms that become complex and take on char acteristics of other variants. The first clinical FTD variant is one in which behavioral abnormalities and personality changes dominate the clinical presentation. This syndrome is usually associated with disease involvement of the frontal and anterior temporal lobes. In addition, there are two language presentations: primary progressive aphasia and semantic dementia (McKhann et al., 2001). The neurologic syndromes of PSP, CBD, and ALS with dementia are familiar to the neurologist because of their neurologic symptoms; it is noteworthy that patients with any of the previously mentioned syndromes routinely develop the psychiatric symptoms reviewed below.

It is important to have a picture of the relationship of the brain and spinal cord to the bones of the skull and vertebral column that house and protect them and the protective layers of connective tissues known as the meninges that cover the CNS; these lie between the bones and brain and spinal cord. The brain is housed within the skull which will be described in much more detail in Section 4 . As you can appreciate by feeling your own skull, the top, front, sides, and back are smoothly curved. The surface of the brain is similarly curved and conforms to the shape of the bones. Note that, in reality, it is really the other way round—brain shape determines the shape of the bones of the skull vault forming the braincase. If the top of the braincase and the brain are removed to reveal the floor of the cranial cavity formed by the bones of the cranial base, it is anything but smooth. Viewed from the lateral aspect and going from anterior to posterior, it is like three descending steps. This structure is shown diagrammatically in Figure 15.1 and shows how different parts of the brain conform to these steps. The first step lies above the nasal and orbital cavities and is known as the anterior cranial fossa ; it houses the frontal lobes of the cerebral hemispheres. The second step is the middle cranial fossa and contains the temporal lobes of each cerebral hemisphere laterally and the midbrain and pons medially. The final step is the posterior cranial fossa where the rest of the brainstem and cerebellum lie. The floor of the posterior fossa is pierced by the foramen magnum through which the medulla oblongata and spinal cord become continuous. The spinal cord occupies the vertebral canal running in the vertebral column. As you can see in Figure 3.5 , in adults, the cord occupies the vertebral canal from the upper border of the first cervical vertebra, the atlas, down to the level of the disc between the first and second lumbar vertebrae.

Domestic cat characteristics: Rounded skull, short snout. Long whiskers. Large canines, small incisors. Cheek teeth with sharp edges for shearing. Large temporalis and masseter muscles of skull. Eyes shifted slightly forward for binocular vision. Large eyes in domestic cats. Constricted pupil in domestic cats is vertical; round in large cats. Top edge of scapula usually higher than tips of thoracic vertebrae. Small rib cage. Five digits on front limb (thumb reduced); four digits on hind limb—may have very reduced first metatarsal or reduced first digit with claw (dewclaw). Walks on toes. Sharp, curved, retractile claws (which keeps them sharp—they don’t walk on them). Forearm rotates (pronates/supinates). Hairy tail. Very flexible body. Spine (back) straight or arched. Can walk in crouched position, as when stalking prey. Bear characteristics: Large, powerful body; powerful limbs appear relatively short. Rear feet wide. Walks on sole and heel of rear foot and usually on digits of front foot. Five digits per limb with long, curved, nonretractile claws. Front claws longer than rear claws. Large head, small eyes. Small, round, erect, furry ears. Large canines; flat, grinding molars. Short tail. Arched back, high shoulder. Grizzly has most prominent shoulder hump and dished, slightly concave face (in profile). Can have very thick layer of fur. Grizzly and brown bear belong to the same species, but differ in geographical range and size. The giant panda is now considered to be a member of the bear family, not the raccoon family.

The muscles of the head consist of the chewing muscles (temporalis, masseter, and digastric) and the facial muscles (zygomaticus, orbicularis oris, etc.). The chewing muscles are thick and volumetric, and they originate and insert on bone. They open and close the lower jaw, with the action taking place at the jaw joint (temporomandibular joint). The facial muscles are thin. They originate either from the skull or from the surface of other muscles, and they generally insert into other facial muscles or into the skin. When they contract, they move the features of the face (eyes, nose, mouth, ears). As they pull the facial features, they often gather the skin into folds and wrinkles that lie perpendicular to the direction of their muscular fibers (perpendicular to the direction of pull). The mouth region receives the most muscles; therefore, it is the most mobile part of the face. Some facial muscles are so thin that they do not create any direct form on the surface (caninus, malaris, orbicularis oculi), whereas other facial muscles or their tendons may create surface form directly (buccinator, levator labii maxillaris, zygomaticus, and depressor labii mandibularis). Facial muscles are generally more visible on the surface in the horse and the ox than in the dog and feline. The facial muscles, as they move the eyes, nose, mouth, and ears, generate whatever facial expressions animals are capable of producing. . . . • Attachment: A short ligament at the inner corner of the eye, whose inner end attaches to the skull. . . . . . . • Action: Eyelid portion: closes eyelids (blinking), primarily by depressing the upper eyelid. Outer portion: tightens and compresses the skin surrounding the eye, protecting the eyeball. . . . . . . • Structure: The orbicularis oculi is a flat, elliptical muscle consisting of two portions. The eyelid portion lies in the upper and lower eyelids, and the outer portion surrounds the eye and lies on the skull. . . .

The anatomy of the orbital vascular bed is complex, with tremendous individual variation. The main arterial supply to the orbit is from the ophthalmic artery, a branch of the internal carotid artery. The external carotid artery normally contributes only to a small extent. However, there are a number of orbital branches of the ophthalmic artery that anastomose with adjacent branches from the external carotid artery, creating important anastomotic communications between the internal and external carotid arterial systems. The venous drainage of the orbit occurs mainly via two ophthalmic veins (superior and inferior) that extend to the cavernous sinus, but there are also connections with the pterygoid plexus of veins, as well as some more anteriorly through the angular vein and the infraorbital vein to the facial vein. A working knowledge of the orbital vasculature and lymphatic systems is important during orbital, extraocular, or ocular surgery. Knowing the anatomy of the blood supply helps one avoid injury to the arteries and veins during operative procedures within the orbit or the eyelid. Inadvertent injury to the vasculature not only distorts the anatomy and disrupts a landmark but also prolongs the surgery and might compromise blood flow to an important orbital or ocular structure. Upon entering the cranium, the internal carotid artery passes through the petrous portion of the temporal bone in the carotid canal and enters the cavernous sinus and middle cranial fossa through the superior part of the forame lacerum . It proceeds forward in the cavernous sinus with the abducens nerve along its side. There it is surrounded by sympathetic nerve fibers (the carotid plexus ) derived from the superior cervical ganglion. It then makes an upward S-shaped turn to form the carotid siphon , passing just medial to the oculomotor, trochlear, and ophthalmic nerves (V1). After turning superiorly in the anterior cavernous sinus, the carotid artery perforates the dura at the medial aspect of the anterior clinoid process and turns posteriorly, inferior to the optic nerve.

The lacrimal system is made up of both the lacrimal secretory system and the nasolacrimal drainage system. The secretory system consists of the glands that make up the tear film (the lacrimal gland, the accessory glands of Krause and Wolfring, and the meibomian glands). The nasolacrimal drainage system consists of the puncta, canaliculi, lacrimal sac, and nasolacrimal duct. These two systems provide for the production and maintenance of the precorneal tear film as well as the drainage of tears from the eye. The normal functioning of these two systems is essential for proper optical refraction, preservation of corneal integrity, and ocular comfort. The physiology of tear production and distribution requires normal eyelid anatomy and mobility. Blinking spreads the tears vertically over the ocular surface. It also adds two important components to the tear film: lipid from the meibomian glands and mucin from the conjunctival goblet cells. The horizontal flow of tears to the medial canthus is along the tear meniscus at the eyelid margin. This requires normal contour and eyelid apposition to the globe and an adequately functioning orbicularis pump mechanism. Both of these functions can be compromised by horizontal and vertical eyelid laxity or by eyelid margin deformities. The lacrimal gland begins in embryologic development as epithelial buds arising from the conjunctiva of the superior temporal fornix. Canalization of the epithelial buds to form ducts begins in utero, but full development of the gland does not occur until three to four years postnatal. The lacrimal gland provides the principal aqueous secretory component of the tear film. It is located just behind the superolateral orbital rim within a depression in the lateral aspect of the orbital roof (the lacrimal gland fossa). The gland’s convex/concave shape reflects its location between the roof of the orbit and the globe. The gland is divided into a larger orbital lobe and a smaller palpebral lobe by the lateral horn of the levator aponeurosis. The orbital lobe lies behind the orbital septum and immediately above the lateral horn of levator.