|
Myodural Bridge
The myodural bridge or miodural ligament is a bridge of connective tissue that extends between the suboccipital muscles and the cervical spinal dura mater, the outer membrane that envelops the spinal cord. It provides a physical connection between the musculoskeletal and nervous systems, and the circulation of cerebrospinal fluid. Its importance has been highlighted by various authors. The myodural bridge is mainly formed by muscular and tendinous components. This bridge originates in the deep layers of the suboccipital muscles, specifically in the rectus capitis posterior minor muscle, and extends to join the dura mater of the cervical spinal cord. This structural connection forms a continuous link from the base of the skull to the top of the cervical spine. Recent studies postulate the existence and functional importance of the myodural bridge in mammals. This membranous anatomical structure was discovered in the mid-90s. According to forensic studies conducted, this ligament ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Connective Tissue
Connective tissue is one of the four primary types of animal tissue, a group of cells that are similar in structure, along with epithelial tissue, muscle tissue, and nervous tissue. It develops mostly from the mesenchyme, derived from the mesoderm, the middle embryonic germ layer. Connective tissue is found in between other tissues everywhere in the body, including the nervous system. The three meninges, membranes that envelop the brain and spinal cord, are composed of connective tissue. Most types of connective tissue consists of three main components: elastic and collagen fibers, ground substance, and cells. Blood and lymph are classed as specialized fluid connective tissues that do not contain fiber. All are immersed in the body water. The cells of connective tissue include fibroblasts, adipocytes, macrophages, mast cells and leukocytes. The term "connective tissue" (in German, ) was introduced in 1830 by Johannes Peter Müller. The tissue was already recognized as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlanto-occipital Joint
The atlanto-occipital joint (''Articulatio atlantooccipitalis'') is an articulation between the atlas bone and the occipital bone. It consists of a pair of condyloid joints. It is a synovial joint. Structure The atlanto-occipital joint is an articulation between the atlas bone and the occipital bone. It consists of a pair of condyloid joints. It is a synovial joint. Ligaments The ligaments connecting the bones are: * Two articular capsules * Posterior atlanto-occipital membrane * Anterior atlanto-occipital membrane Capsule The capsules of the atlantooccipital articulation surround the condyles of the occipital bone, and connect them with the articular processes of the atlas: they are thin and loose. Variation Atlantooccipital fusion, also known as occipitalization of the atlas, is a congenital or acquired anomaly characterized by the partial or complete fusion of the atlas to the base of the occipital bone. It is found in 0.12% to 0.72% of the population. This fusio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cognitive Disorder
Neurocognitive disorders (NCDs), also known as cognitive disorders (CDs), are a category of mental health disorders that primarily affect cognitive abilities including learning, memory, perception, and problem-solving. Neurocognitive disorders include delirium, mild neurocognitive disorders, and major neurocognitive disorder (also known as dementia). They are defined by deficits in cognitive ability that are acquired (as opposed to developmental), typically represent decline, and may have an underlying brain pathology. The DSM-5 defines six key domains of cognitive function: executive function, learning and memory, perceptual-motor function, language, complex attention, and social cognition. Although Alzheimer's disease accounts for the majority of cases of neurocognitive disorders, there are various medical conditions that affect mental functions such as memory, thinking, and the ability to reason, including frontotemporal degeneration, Huntington's disease, dementia with L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavernous Sinus
The cavernous sinus within the human head is one of the dural venous sinuses creating a cavity called the lateral sellar compartment bordered by the temporal bone of the skull and the sphenoid bone, lateral to the sella turcica. Structure The cavernous sinus is one of the dural venous sinuses of the head. It is a network of veins that sit in a cavity. It sits on both sides of the sphenoidal bone and pituitary gland, approximately 1 × 2 cm in size in an adult. The carotid siphon of the internal carotid artery, and cranial nerves III, IV, V (branches V1 and V2) and VI all pass through this blood filled space. Both sides of cavernous sinus are connected to each other via intercavernous sinuses. The cavernous sinus lies in between the inner and outer layers of dura mater. Nearby structures * Above: optic tract, optic chiasma, internal carotid artery. * Inferiorly: foramen lacerum, and the junction of the body and greater wing of sphenoid bone. * Medially: p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Volume
Blood volume (volemia) is the volume of blood ( blood cells and plasma) in the circulatory system of any individual. Humans A typical adult has a blood volume of approximately 5 liters, with females and males having approximately the same blood percentage by weight (approx 7 to 8%) Blood volume is regulated by the kidneys. Blood volume (BV) can be calculated given the hematocrit (HC; the fraction of blood that is red blood cells) and plasma volume (PV), with the hematocrit being regulated via the blood oxygen content regulator: :BV = \frac Blood volume measurement may be used in people with congestive heart failure, chronic hypertension, kidney failure and critical care. The use of relative blood volume changes during dialysis is of questionable utility. Total Blood Volume can be measured manually via the Dual Isotope or Dual Tracer Technique, a classic technique, available since the 1950s. This technique requires double labeling of the blood; that is 2 injections and 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertigo
Vertigo is a condition in which a person has the sensation that they are moving, or that objects around them are moving, when they are not. Often it feels like a spinning or swaying movement. It may be associated with nausea, vomiting, perspiration, or difficulties walking. It is typically worse when the head is moved. Vertigo is the most common type of dizziness. The most common disorders that result in vertigo are benign paroxysmal positional vertigo (BPPV), Ménière's disease, and vestibular neuritis. Less common causes include stroke, brain tumors, brain injury, multiple sclerosis, migraines, trauma, and uneven pressures between the middle ears. Physiologic vertigo may occur following being exposed to motion for a prolonged period such as when on a ship or simply following spinning with the eyes closed. Other causes may include toxin exposures such as to carbon monoxide, alcohol, or aspirin. Vertigo typically indicates a problem in a part of the vestibular system. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Headache
A headache, also known as cephalalgia, is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of Depression (mood), depression in those with severe headaches. Headaches can occur as a result of many conditions. There are a number of different classification systems for headaches. The most well-recognized is that of the International Headache Society, which classifies it into more than 150 types of Primary headache disorder, primary and secondary headaches. Causes of headaches may include dehydration; fatigue; sleep deprivation; Stress (biology), stress; the effects of medications (overuse) and recreational drugs, including withdrawal; viral infections; loud noises; head injury; rapid ingestion of a very cold food or beverage; and dental or sinus issues (such as sinusitis). Treatment of a headache depends on the underlying cause, but commonly involves analgesic, pain medication (esp ... [...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] |
Rectus Capitis Posterior Minor Muscle
The rectus capitis posterior minor (or rectus capitis posticus minor) is a muscle in the upper back part of the neck. It is one of the suboccipital muscles. Its inferior attachment is at the posterior arch of atlas; its superior attachment is onto the occipital bone at and below the inferior nuchal line. The muscle is innervated by the suboccipital nerve (the posterior ramus of first cervical spinal nerve). The muscle acts as a weak extensor of the head. Anatomy The rectus capitis posterior major muscle is one of the suboccipital muscles. The muscle extends vertically superior-ward from its inferiro attachment to its superior attachment. The muscle becomes broader superiorly. Attachments The inferior attachment is (by a narrow tendon) onto the posterior tubercle of the posterior arch of atlas. Its superior attachment is onto the medial portion of the inferior nuchal line and the external surface of the occipital bone inferior to it (between this line superiorly and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rectus Capitis Posterior Major Muscle
The rectus capitis posterior major (or rectus capitis posticus major) is a muscle in the upper back part of the neck. It is one of the suboccipital muscles. Its inferior attachment is at the spinous process of the axis (Second cervical vertebra); its superior attachment is onto the outer surface of the occipital bone on and around the side part of the inferior nuchal line. The muscle is innervated by the suboccipital nerve (the posterior ramus of cervical spinal nerve C1). The muscle acts to extend the head and rotate the head to its side. Anatomy The rectus capitis posterior major muscle is one of the suboccipital muscles. It forms the superomedial boundary of the suboccipital triangle. The muscle extends obliquely superiolaterally from its inferior attachment to its superior attachment. It becomes broader superiorly. Attachments Its inferior attachment is (via a pointed tendon) at (the external aspect of) the (bifid) spinous process of the axis (cervical vertebra C2) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Obliques Capitis
The obliquus capitis inferior muscle () is a muscle in the upper back of the neck. It is one of the suboccipital muscles. Its inferior attachment is at the spinous process of the axis; its superior attachment is at the transverse process of the atlas. It is innervated by the suboccipital nerve (the posterior ramus of first cervical spinal nerve). The muscle rotates the head to its side. Despite what its name suggest, it is the only capitis (Latin: "head") muscle that does not actually attach to the skull. Anatomy The obliquus capitis inferior is one of the suboccipital muscles (and the only one of these to have no attachment to the skull). It is larger than the obliquus capitis superior muscle. It forms the inferolateral boundary of the suboccipital triangle. The muscle extends laterally and somewhat superiorly from its inferior attachment to its superior attachment. Attachments its inferior attachment is at the lateral external aspect of the bifid spinous process of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebromedullary Cistern
The cisterna magna (posterior cerebellomedullary cistern, or cerebellomedullary cistern) is the largest of the subarachnoid cisterns. It occupies the space created by the angle between the caudal/inferior surface of the cerebellum, and the dorsal/posterior surface of the medulla oblongata (it is created by the arachnoidea that bridges this angle). The fourth ventricle communicates with the cistern via the unpaired midline median aperture. It is continuous inferiorly with the subarachnoid space of the spinal canal. The cisterna magna contains the two vertebral arteries, the origins of the two posterior inferior cerebellar arteries, the glossopharyngeal nerve (CN IX), vagus nerve (CN X), accessory nerve (CN XI), hypoglossal nerve (XII), and choroid plexus. The vertebral artery and posterior inferior cerebellar artery of either side pass traverse either lateral portion of the cistern. Etymology The ''Terminologia Anatomica'' classifies the terms ''cisterna magna'' and ''poste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
