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Cerebrospinal Fluid
Cerebrospinal fluid (CSF) is a clear, colorless body fluid found within the tissue that surrounds the brain and spinal cord of all vertebrates. CSF is produced by specialised ependymal cells in the choroid plexus of the ventricles of the brain, and absorbed in the arachnoid granulations. There is about 125 mL of CSF at any one time, and about 500 mL is generated every day. CSF acts as a shock absorber, cushion or buffer, providing basic mechanical and immunological protection to the brain inside the skull. CSF also serves a vital function in the cerebral autoregulation of cerebral blood flow. CSF occupies the subarachnoid space (between the arachnoid mater and the pia mater) and the ventricular system around and inside the brain and spinal cord. It fills the ventricles of the brain, cisterns, and sulci, as well as the central canal of the spinal cord. There is also a connection from the subarachnoid space to the bony labyrinth of the inner ear via the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subarachnoid Space
In anatomy, the meninges (, ''singular:'' meninx ( or ), ) are the three membranes that envelop the brain and spinal cord. In mammals, the meninges are the dura mater, the arachnoid mater, and the pia mater. Cerebrospinal fluid is located in the subarachnoid space between the arachnoid mater and the pia mater. The primary function of the meninges is to protect the central nervous system. Structure Dura mater The dura mater ( la, tough mother) (also rarely called ''meninx fibrosa'' or ''pachymeninx'') is a thick, durable membrane, closest to the skull and vertebrae. The dura mater, the outermost part, is a loosely arranged, fibroelastic layer of cells, characterized by multiple interdigitating cell processes, no extracellular collagen, and significant extracellular spaces. The middle region is a mostly fibrous portion. It consists of two layers: the endosteal layer, which lies closest to the skull, and the inner meningeal layer, which lies closer to the brain. It contains ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulcus (neuroanatomy)
In neuroanatomy, a sulcus (Latin: "furrow", pl. ''sulci'') is a depression or groove in the cerebral cortex. It surrounds a gyrus (pl. gyri), creating the characteristic folded appearance of the brain in humans and other mammals. The larger sulci are usually called fissures. Structure Sulci, the grooves, and gyri, the folds or ridges, make up the folded surface of the cerebral cortex. Larger or deeper sulci are termed fissures, and in many cases the two terms are interchangeable. The folded cortex creates a larger surface area for the brain in humans and other mammals. When looking at the human brain, two-thirds of the surface are hidden in the grooves. The sulci and fissures are both grooves in the cortex, but they are differentiated by size. A sulcus is a shallower groove that surrounds a gyrus. A fissure is a large furrow that divides the brain into lobes and also into the two hemispheres as the longitudinal fissure. Importance of expanded surface area As the sur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harvey Cushing
Harvey Williams Cushing (April 8, 1869 – October 7, 1939) was an American neurosurgeon, pathologist, writer, and draftsman. A pioneer of brain surgery, he was the first exclusive neurosurgeon and the first person to describe Cushing's disease. He wrote a biography of physician William Osler in three volumes. Early life Harvey Cushing was born in Cleveland, Ohio. His parents were Elizabeth Maria "Betsey M." Williams and Henry Kirke Cushing, a physician whose ancestors came to Hingham, Massachusetts, as Puritans in the 17th century. Harvey was the youngest of ten children. Education As a child, Cushing attended the Cleveland Manual Training School, which expanded his interest in science and medicine. The school's emphasis on experimental training and a "physics-focused" approach to education played an important role in influencing Cushing towards a career in medical surgery. The school's manual dexterity training program also contributed to Cushing's future success as a surg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emanuel Swedenborg
Emanuel Swedenborg (, ; born Emanuel Swedberg; 29 March 1772) was a Swedish pluralistic-Christian theologian, scientist, philosopher and mystic. He became best known for his book on the afterlife, ''Heaven and Hell'' (1758). Swedenborg had a prolific career as an inventor and scientist. In 1741, at 53, he entered into a spiritual phase in which he began to experience dreams and visions, notably on Easter Weekend, on 6 April 1744. His experiences culminated in a "spiritual awakening" in which he received a revelation that Jesus Christ had appointed him to write ''The Heavenly Doctrine'' to reform Christianity. According to ''The Heavenly Doctrine'', the Lord had opened Swedenborg's spiritual eyes so that from then on, he could freely visit heaven and hell to converse with angels, demons and other spirits, and that the Last Judgment had already occurred in 1757, the year before the 1758 publication of ''De Nova Hierosolyma et ejus doctrina coelesti'' (English: ''Concerning the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hippocrates
Hippocrates of Kos (; grc-gre, Ἱπποκράτης ὁ Κῷος, Hippokrátēs ho Kôios; ), also known as Hippocrates II, was a Greek physician of the classical period who is considered one of the most outstanding figures in the history of medicine. He is traditionally referred to as the "Father of Medicine" in recognition of his lasting contributions to the field, such as the use of prognosis and clinical observation, the systematic categorization of diseases, or the formulation of humoral theory. The Hippocratic school of medicine revolutionized ancient Greek medicine, establishing it as a discipline distinct from other fields with which it had traditionally been associated ( theurgy and philosophy), thus establishing medicine as a profession. However, the achievements of the writers of the Hippocratic Corpus, the practitioners of Hippocratic medicine, and the actions of Hippocrates himself were often conflated; thus very little is known about what Hippocrates actual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meningitis
Meningitis is acute or chronic inflammation of the protective membranes covering the brain and spinal cord, collectively called the meninges. The most common symptoms are fever, headache, and neck stiffness. Other symptoms include confusion or altered consciousness, nausea, vomiting, and an inability to tolerate light or loud noises. Young children often exhibit only nonspecific symptoms, such as irritability, drowsiness, or poor feeding. A non-blanching rash (a rash that does not fade when a glass is rolled over it) may also be present. The inflammation may be caused by infection with viruses, bacteria or other microorganisms. Non-infectious causes include malignancy (cancer), subarachnoid haemorrhage, chronic inflammatory disease (sarcoidosis) and certain drugs. Meningitis can be life-threatening because of the inflammation's proximity to the brain and spinal cord; therefore, the condition is classified as a medical emergency. A lumbar puncture, in which a needle is ins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encephalitis
Encephalitis is inflammation of the brain. The severity can be variable with symptoms including reduction or alteration in consciousness, headache, fever, confusion, a stiff neck, and vomiting. Complications may include seizures, hallucinations, trouble speaking, memory problems, and problems with hearing. Causes of encephalitis include viruses such as herpes simplex virus and rabies virus as well as bacteria, fungi, or parasites. Other causes include autoimmune diseases and certain medications. In many cases the cause remains unknown. Risk factors include a weak immune system. Diagnosis is typically based on symptoms and supported by blood tests, medical imaging, and analysis of cerebrospinal fluid. Certain types are preventable with vaccines. Treatment may include antiviral medications (such as acyclovir), anticonvulsants, and corticosteroids. Treatment generally takes place in hospital. Some people require artificial respiration. Once the immediate problem is under co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intracranial Pressure
Intracranial pressure (ICP) is the pressure exerted by fluids such as cerebrospinal fluid (CSF) inside the skull and on the brain tissue. ICP is measured in millimeters of mercury ( mmHg) and at rest, is normally 7–15 mmHg for a supine adult. The body has various mechanisms by which it keeps the ICP stable, with CSF pressures varying by about 1 mmHg in normal adults through shifts in production and absorption of CSF. Changes in ICP are attributed to volume changes in one or more of the constituents contained in the cranium. CSF pressure has been shown to be influenced by abrupt changes in intrathoracic pressure during coughing (which is induced by contraction of the diaphragm and abdominal wall muscles, the latter of which also increases intra-abdominal pressure), the valsalva maneuver, and communication with the vasculature ( venous and arterial systems). Intracranial hypertension (IH), also called increased ICP (IICP) or raised intracranial pressure (RICP), is elevation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lumbar Puncture
Lumbar puncture (LP), also known as a spinal tap, is a medical procedure in which a needle is inserted into the spinal canal, most commonly to collect cerebrospinal fluid (CSF) for diagnostic testing. The main reason for a lumbar puncture is to help diagnose diseases of the central nervous system, including the brain and spine. Examples of these conditions include meningitis and subarachnoid hemorrhage. It may also be used therapeutically in some conditions. Increased intracranial pressure (pressure in the skull) is a contraindication, due to risk of brain matter being compressed and pushed toward the spine. Sometimes, lumbar puncture cannot be performed safely (for example due to a severe bleeding tendency). It is regarded as a safe procedure, but post-dural-puncture headache is a common side effect if a small atraumatic needle is not used. The procedure is typically performed under local anesthesia using a sterile technique. A hypodermic needle is used to access the suba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cilium
The cilium, plural cilia (), is a membrane-bound organelle found on most types of eukaryotic cell, and certain microorganisms known as ciliates. Cilia are absent in bacteria and archaea. The cilium has the shape of a slender threadlike projection that extends from the surface of the much larger cell body. Eukaryotic flagella found on sperm cells and many protozoans have a similar structure to motile cilia that enables swimming through liquids; they are longer than cilia and have a different undulating motion. There are two major classes of cilia: ''motile'' and ''non-motile'' cilia, each with a subtype, giving four types in all. A cell will typically have one primary cilium or many motile cilia. The structure of the cilium core called the axoneme determines the cilium class. Most motile cilia have a central pair of single microtubules surrounded by nine pairs of double microtubules called a 9+2 axoneme. Most non-motile cilia have a 9+0 axoneme that lacks the central pai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perilymph
Perilymph is an extracellular fluid located within the inner ear. It is found within the scala tympani and scala vestibuli of the cochlea. The ionic composition of perilymph is comparable to that of plasma and cerebrospinal fluid. The major cation in perilymph is sodium, with the values of sodium and potassium concentration in the perilymph being 138 mM and 6.9 mM, respectively. It is also named Cotunnius' liquid and liquor cotunnii for Domenico Cotugno. Structure The inner ear has two major parts, the cochlea and the vestibular organ. They are connected in a series of canals in the temporal bone referred to as the bony labyrinth. The bone canals are separated by the membranes in parallel spaces referred to as the membranous labyrinth. The membranous labyrinth contains endolymph, and is surrounded by perilymph. The perilymph in the bony labyrinth serves as connection to the cerebrospinal fluid of the subarachnoid space via the perilymphatic duct. Compositi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perilymphatic Duct
In the anatomy of the human ear, the perilymphatic duct is where the perilymphatic space (vestibule of the ear) is connected to the subarachnoid space. This works as a type of shunt to eliminate excess perilymph fluid from the perilymphatic space around the cochlea of the ear. Perilymph is continuous with cerebrospinal fluid (CSF) in the subarachnoid space. CSF pressure abnormalities do not generally have clinical impact on the inner ear which is explained physically by the bore diameter and length of the perilymphatic duct. This duct goes through the skull and is parallel with but not directly associated with the endolymphatic duct. The duct is lined by an epithelium Epithelium or epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. It is a thin, continuous, protective layer of compactly packed cells with a little intercel .... References Ear {{anatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
