Vestibule, Labyrinth: An oval, bony chamber of the inner ear, part of the bony labyrinth. It is continuous with bony COCHLEA anteriorly, and SEMICIRCULAR CANALS posteriorly. The vestibule contains two communicating sacs (utricle and saccule) of the balancing apparatus. The oval window on its lateral wall is occupied by the base of the STAPES of the MIDDLE EAR.Labyrinth Diseases: Pathological processes of the inner ear (LABYRINTH) which contains the essential apparatus of hearing (COCHLEA) and balance (SEMICIRCULAR CANALS).Ear, Inner: The essential part of the hearing organ consists of two labyrinthine compartments: the bony labyrinthine and the membranous labyrinth. The bony labyrinth is a complex of three interconnecting cavities or spaces (COCHLEA; VESTIBULAR LABYRINTH; and SEMICIRCULAR CANALS) in the TEMPORAL BONE. Within the bony labyrinth lies the membranous labyrinth which is a complex of sacs and tubules (COCHLEAR DUCT; SACCULE AND UTRICLE; and SEMICIRCULAR DUCTS) forming a continuous space enclosed by EPITHELIUM and connective tissue. These spaces are filled with LABYRINTHINE FLUIDS of various compositions.Semicircular Canals: Three long canals (anterior, posterior, and lateral) of the bony labyrinth. They are set at right angles to each other and are situated posterosuperior to the vestibule of the bony labyrinth (VESTIBULAR LABYRINTH). The semicircular canals have five openings into the vestibule with one shared by the anterior and the posterior canals. Within the canals are the SEMICIRCULAR DUCTS.Placenta: A highly vascularized mammalian fetal-maternal organ and major site of transport of oxygen, nutrients, and fetal waste products. It includes a fetal portion (CHORIONIC VILLI) derived from TROPHOBLASTS and a maternal portion (DECIDUA) derived from the uterine ENDOMETRIUM. The placenta produces an array of steroid, protein and peptide hormones (PLACENTAL HORMONES).Endolymphatic Duct: The part of the membranous labyrinth that traverses the bony vestibular aqueduct and emerges through the bone of posterior cranial fossa (CRANIAL FOSSA, POSTERIOR) where it expands into a blind pouch called the endolymphatic sac.Placentation: The development of the PLACENTA, a highly vascularized mammalian fetal-maternal organ and major site of transport of oxygen, nutrients, and fetal waste products between mother and FETUS. The process begins at FERTILIZATION, through the development of CYTOTROPHOBLASTS and SYNCYTIOTROPHOBLASTS, the formation of CHORIONIC VILLI, to the progressive increase in BLOOD VESSELS to support the growing fetus.Endolymphatic Hydrops: An accumulation of ENDOLYMPH in the inner ear (LABYRINTH) leading to buildup of pressure and distortion of intralabyrinthine structures, such as COCHLEA and SEMICIRCULAR CANALS. It is characterized by SENSORINEURAL HEARING LOSS; TINNITUS; and sometimes VERTIGO.Cochlea: The part of the inner ear (LABYRINTH) that is concerned with hearing. It forms the anterior part of the labyrinth, as a snail-like structure that is situated almost horizontally anterior to the VESTIBULAR LABYRINTH.Endolymph: The lymph fluid found in the membranous labyrinth of the ear. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Vestibular Diseases: Pathological processes of the VESTIBULAR LABYRINTH which contains part of the balancing apparatus. Patients with vestibular diseases show instability and are at risk of frequent falls.Vestibular Nuclei: The four cellular masses in the floor of the fourth ventricle giving rise to a widely dispersed special sensory system. Included is the superior, medial, inferior, and LATERAL VESTIBULAR NUCLEUS. (From Dorland, 27th ed)Petrous Bone: The dense rock-like part of temporal bone that contains the INNER EAR. Petrous bone is located at the base of the skull. Sometimes it is combined with the MASTOID PROCESS and called petromastoid part of temporal bone.Vestibular Nucleus, Lateral: Vestibular nucleus lying immediately superior to the inferior vestibular nucleus and composed of large multipolar nerve cells. Its upper end becomes continuous with the superior vestibular nucleus.Vestibular Nerve: The vestibular part of the 8th cranial nerve (VESTIBULOCOCHLEAR NERVE). The vestibular nerve fibers arise from neurons of Scarpa's ganglion and project peripherally to vestibular hair cells and centrally to the VESTIBULAR NUCLEI of the BRAIN STEM. These fibers mediate the sense of balance and head position.Caloric Tests: Elicitation of a rotatory nystagmus by stimulating the semicircular canals with water or air which is above or below body temperature. In warm caloric stimulation a rotatory nystagmus is developed toward the side of the stimulated ear; in cold, away from the stimulated side. Absence of nystagmus indicates the labyrinth is not functioning.Cranial Fossa, Posterior: The infratentorial compartment that contains the CEREBELLUM and BRAIN STEM. It is formed by the posterior third of the superior surface of the body of the sphenoid (SPHENOID BONE), by the occipital, the petrous, and mastoid portions of the TEMPORAL BONE, and the posterior inferior angle of the PARIETAL BONE.Mesylates: Organic salts or esters of methanesulfonic acid.Saxitoxin: A compound that contains a reduced purine ring system but is not biosynthetically related to the purine alkaloids. It is a poison found in certain edible mollusks at certain times; elaborated by GONYAULAX and consumed by mollusks, fishes, etc. without ill effects. It is neurotoxic and causes RESPIRATORY PARALYSIS and other effects in MAMMALS, known as paralytic SHELLFISH poisoning.Shab Potassium Channels: A subfamily of shaker potassium channels that shares homology with its founding member, Shab protein, Drosophila. They regulate delayed rectifier currents in the NERVOUS SYSTEM of DROSOPHILA and in the SKELETAL MUSCLE and HEART of VERTEBRATES.Endolymphatic Sac: The blind pouch at the end of the endolymphatic duct. It is a storage reservoir for excess ENDOLYMPH, formed by the blood vessels in the membranous labyrinth.Ion Channel Gating: The opening and closing of ion channels due to a stimulus. The stimulus can be a change in membrane potential (voltage-gated), drugs or chemical transmitters (ligand-gated), or a mechanical deformation. Gating is thought to involve conformational changes of the ion channel which alters selective permeability.Perilymph: The fluid separating the membranous labyrinth from the osseous labyrinth of the ear. It is entirely separate from the ENDOLYMPH which is contained in the membranous labyrinth. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1396, 642)Trophoblasts: Cells lining the outside of the BLASTOCYST. After binding to the ENDOMETRIUM, trophoblasts develop into two distinct layers, an inner layer of mononuclear cytotrophoblasts and an outer layer of continuous multinuclear cytoplasm, the syncytiotrophoblasts, which form the early fetal-maternal interface (PLACENTA).Hydrocharitaceae: A plant family of the order Hydrocharitales, subclass ALISMATIDAE, class Liliopsida (monocotyledons).Fenestration, Labyrinth: The surgical creation of a new opening in the labyrinth of the ear for the restoration of hearing in cases of OTOSCLEROSIS. (Dorland, 27th ed)Meniere Disease: A disease of the inner ear (LABYRINTH) that is characterized by fluctuating SENSORINEURAL HEARING LOSS; TINNITUS; episodic VERTIGO; and aural fullness. It is the most common form of endolymphatic hydrops.Oocytes: Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).Reflex, Vestibulo-Ocular: A reflex wherein impulses are conveyed from the cupulas of the SEMICIRCULAR CANALS and from the OTOLITHIC MEMBRANE of the SACCULE AND UTRICLE via the VESTIBULAR NUCLEI of the BRAIN STEM and the median longitudinal fasciculus to the OCULOMOTOR NERVE nuclei. It functions to maintain a stable retinal image during head rotation by generating appropriate compensatory EYE MOVEMENTS.Embryo Loss: Early pregnancy loss during the EMBRYO, MAMMALIAN stage of development. In the human, this period comprises the second through eighth week after fertilization.Stapes: One of the three ossicles of the middle ear. It transmits sound vibrations from the INCUS to the internal ear (Ear, Internal see LABYRINTH).Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Rotation: Motion of an object in which either one or more points on a line are fixed. It is also the motion of a particle about a fixed point. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Vertigo: An illusion of movement, either of the external world revolving around the individual or of the individual revolving in space. Vertigo may be associated with disorders of the inner ear (EAR, INNER); VESTIBULAR NERVE; BRAINSTEM; or CEREBRAL CORTEX. Lesions in the TEMPORAL LOBE and PARIETAL LOBE may be associated with FOCAL SEIZURES that may feature vertigo as an ictal manifestation. (From Adams et al., Principles of Neurology, 6th ed, pp300-1)Cochlear Diseases: Pathological processes of the snail-like structure (COCHLEA) of the inner ear (LABYRINTH) which can involve its nervous tissue, blood vessels, or fluid (ENDOLYMPH).Magnetic Resonance Imaging: Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.Labyrinthitis: Inflammation of the inner ear (LABYRINTH).Posterior Cerebral Artery: Artery formed by the bifurcation of the BASILAR ARTERY. Branches of the posterior cerebral artery supply portions of the OCCIPITAL LOBE; PARIETAL LOBE; inferior temporal gyrus, brainstem, and CHOROID PLEXUS.Conotoxins: Peptide neurotoxins from the marine fish-hunting snails of the genus CONUS. They contain 13 to 29 amino acids which are strongly basic and are highly cross-linked by disulfide bonds. There are three types of conotoxins, omega-, alpha-, and mu-. OMEGA-CONOTOXINS inhibit voltage-activated entry of calcium into the presynaptic membrane and therefore the release of ACETYLCHOLINE. Alpha-conotoxins inhibit the postsynaptic acetylcholine receptor. Mu-conotoxins prevent the generation of muscle action potentials. (From Concise Encyclopedia Biochemistry and Molecular Biology, 3rd ed)Nasal Cavity: The proximal portion of the respiratory passages on either side of the NASAL SEPTUM. Nasal cavities, extending from the nares to the NASOPHARYNX, are lined with ciliated NASAL MUCOSA.Spiral Ligament of Cochlea: A spiral thickening of the fibrous lining of the cochlear wall. Spiral ligament secures the membranous COCHLEAR DUCT to the bony spiral canal of the COCHLEA. Its spiral ligament fibrocytes function in conjunction with the STRIA VASCULARIS to mediate cochlear ion homeostasis.Sodium Channels: Ion channels that specifically allow the passage of SODIUM ions. A variety of specific sodium channel subtypes are involved in serving specialized functions such as neuronal signaling, CARDIAC MUSCLE contraction, and KIDNEY function.Xenopus laevis: The commonest and widest ranging species of the clawed "frog" (Xenopus) in Africa. This species is used extensively in research. There is now a significant population in California derived from escaped laboratory animals.Ethyl Methanesulfonate: An antineoplastic agent with alkylating properties. It also acts as a mutagen by damaging DNA and is used experimentally for that effect.Posterior Cruciate Ligament: A strong ligament of the knee that originates from the anterolateral surface of the medial condyle of the femur, passes posteriorly and inferiorly between the condyles, and attaches to the posterior intercondylar area of the tibia.Scandentia: An order of the class MAMMALS that consists of one family, TUPAIIDAE (tree shrews), 5 genera (one of which is TUPAIA), and 16 species. Their recent distribution is from India to the Philippines, southern China to Java, Borneo, Sumatra, Bali, and other islands in those regions.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Scala Tympani: The lower chamber of the COCHLEA, extending from the round window to the helicotrema (the opening at the apex that connects the PERILYMPH-filled spaces of scala tympani and SCALA VESTIBULI).Xenopus: An aquatic genus of the family, Pipidae, occurring in Africa and distinguished by having black horny claws on three inner hind toes.Vestibular Function Tests: A number of tests used to determine if the brain or balance portion of the inner ear are causing dizziness.Potassium Channels, Voltage-Gated: Potassium channel whose permeability to ions is extremely sensitive to the transmembrane potential difference. The opening of these channels is induced by the membrane depolarization of the ACTION POTENTIAL.Shaker Superfamily of Potassium Channels: Voltage-gated potassium channels whose primary subunits contain six transmembrane segments and form tetramers to create a pore with a voltage sensor. They are related to their founding member, shaker protein, Drosophila.Potassium Channels: Cell membrane glycoproteins that are selectively permeable to potassium ions. At least eight major groups of K channels exist and they are made up of dozens of different subunits.Round Window, Ear: Fenestra of the cochlea, an opening in the basal wall between the MIDDLE EAR and the INNER EAR, leading to the cochlea. It is closed by a secondary tympanic membrane.Scorpion Venoms: Venoms from animals of the order Scorpionida of the class Arachnida. They contain neuro- and hemotoxins, enzymes, and various other factors that may release acetylcholine and catecholamines from nerve endings. Of the several protein toxins that have been characterized, most are immunogenic.Cochlear Duct: A spiral tube that is firmly suspended in the bony shell-shaped part of the cochlea. This ENDOLYMPH-filled cochlear duct begins at the vestibule and makes 2.5 turns around a core of spongy bone (the modiolus) thus dividing the PERILYMPH-filled spiral canal into two channels, the SCALA VESTIBULI and the SCALA TYMPANI.Mutagenesis, Site-Directed: Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.Metrial Gland: Collection of granular epithelial cells in the uterine muscle beneath the placenta that develop during pregnancy in certain species of animals.Tetraethylammonium: A potassium-selective ion channel blocker. (From J Gen Phys 1994;104(1):173-90)Medical Illustration: The field which deals with illustrative clarification of biomedical concepts, as in the use of diagrams and drawings. The illustration may be produced by hand, photography, computer, or other electronic or mechanical methods.Vestibulocochlear Nerve Diseases: Pathological processes of the VESTIBULOCOCHLEAR NERVE, including the branches of COCHLEAR NERVE and VESTIBULAR NERVE. Common examples are VESTIBULAR NEURITIS, cochlear neuritis, and ACOUSTIC NEUROMA. Clinical signs are varying degree of HEARING LOSS; VERTIGO; and TINNITUS.Aminacrine: A highly fluorescent anti-infective dye used clinically as a topical antiseptic and experimentally as a mutagen, due to its interaction with DNA. It is also used as an intracellular pH indicator.Pregnancy, Animal: The process of bearing developing young (EMBRYOS or FETUSES) in utero in non-human mammals, beginning from FERTILIZATION to BIRTH.Otolithic Membrane: A gelatinous membrane overlying the acoustic maculae of SACCULE AND UTRICLE. It contains minute crystalline particles (otoliths) of CALCIUM CARBONATE and protein on its outer surface. In response to head movement, the otoliths shift causing distortion of the vestibular hair cells which transduce nerve signals to the BRAIN for interpretation of equilibrium.Uveitis, Posterior: Inflammation of the choroid as well as the retina and vitreous body. Some form of visual disturbance is usually present. The most important characteristics of posterior uveitis are vitreous opacities, choroiditis, and chorioretinitis.Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Gene Expression Regulation, Developmental: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action during the developmental stages of an organism.Cysteine: A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.Membrane Potentials: The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Kv1.3 Potassium Channel: A delayed rectifier subtype of shaker potassium channels that is the predominant VOLTAGE-GATED POTASSIUM CHANNEL of T-LYMPHOCYTES.Amino Acid Substitution: The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.Plasma Membrane Neurotransmitter Transport Proteins: A family of neurotransmitter transporter proteins that facilitate NEUROTRANSMITTER reuptake into PRESYNAPTIC TERMINALS. They may play a role in regulating the intensity and duration of neurotransmission.Fetal Weight: The weight of the FETUS in utero. It is usually estimated by various formulas based on measurements made during PRENATAL ULTRASONOGRAPHY.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Patch-Clamp Techniques: An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.Hypothalamus, Posterior: The part of the hypothalamus posterior to the middle region consisting of several nuclei including the medial maxillary nucleus, lateral mammillary nucleus, and posterior hypothalamic nucleus (posterior hypothalamic area). The posterior hypothalamic area is concerned with control of sympathetic responses and is sensitive to conditions of decreasing temperature and controls the mechanisms for the conservation and increased production of heat.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Hair Cells, Auditory: Sensory cells in the organ of Corti, characterized by their apical stereocilia (hair-like projections). The inner and outer hair cells, as defined by their proximity to the core of spongy bone (the modiolus), change morphologically along the COCHLEA. Towards the cochlear apex, the length of hair cell bodies and their apical STEREOCILIA increase, allowing differential responses to various frequencies of sound.Delayed Rectifier Potassium Channels: A group of slow opening and closing voltage-gated potassium channels. Because of their delayed activation kinetics they play an important role in controlling ACTION POTENTIAL duration.Saccule and Utricle: Two membranous sacs within the vestibular labyrinth of the INNER EAR. The saccule communicates with COCHLEAR DUCT through the ductus reuniens, and communicates with utricle through the utriculosaccular duct from which the ENDOLYMPHATIC DUCT arises. The utricle and saccule have sensory areas (acoustic maculae) which are innervated by the VESTIBULAR NERVE.Nystagmus, Physiologic: Involuntary rhythmical movements of the eyes in the normal person. These can be naturally occurring as in end-position (end-point, end-stage, or deviational) nystagmus or induced by the optokinetic drum (NYSTAGMUS, OPTOKINETIC), caloric test, or a rotating chair.Chinchilla: A genus of the family Chinchillidae which consists of three species: C. brevicaudata, C. lanigera, and C. villidera. They are used extensively in biomedical research.Vestibular Aqueduct: A small bony canal linking the vestibule of the inner ear to the posterior part of the internal surface of the petrous TEMPORAL BONE. It transmits the endolymphatic duct and two small blood vessels.Biophysical Phenomena: The physical characteristics and processes of biological systems.Ossification of Posterior Longitudinal Ligament: A calcification of the posterior longitudinal ligament of the spinal column, usually at the level of the cervical spine. It is often associated with anterior ankylosing hyperostosis.Ear Neoplasms: Tumors or cancer of any part of the hearing and equilibrium system of the body (the EXTERNAL EAR, the MIDDLE EAR, and the INNER EAR).Charybdotoxin: A 37-amino acid residue peptide isolated from the scorpion Leiurus quinquestriatus hebraeus. It is a neurotoxin that inhibits calcium activated potassium channels.Head: The upper part of the human body, or the front or upper part of the body of an animal, typically separated from the rest of the body by a neck, and containing the brain, mouth, and sense organs.Head Movements: Voluntary or involuntary motion of head that may be relative to or independent of body; includes animals and humans.Protein Structure, Tertiary: The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.Nystagmus, Pathologic: Involuntary movements of the eye that are divided into two types, jerk and pendular. Jerk nystagmus has a slow phase in one direction followed by a corrective fast phase in the opposite direction, and is usually caused by central or peripheral vestibular dysfunction. Pendular nystagmus features oscillations that are of equal velocity in both directions and this condition is often associated with visual loss early in life. (Adams et al., Principles of Neurology, 6th ed, p272)Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Neoplasms, Adnexal and Skin Appendage: Neoplasms composed of sebaceous or sweat gland tissue or tissue of other skin appendages. The concept does not refer to neoplasms located in the sebaceous or sweat glands or in the other skin appendages.In Situ Hybridization: A technique that localizes specific nucleic acid sequences within intact chromosomes, eukaryotic cells, or bacterial cells through the use of specific nucleic acid-labeled probes.Hair Cells, Vestibular: Sensory cells in the acoustic maculae with their apical STEREOCILIA embedded in a gelatinous OTOLITHIC MEMBRANE. These hair cells are stimulated by the movement of otolithic membrane, and impulses are transmitted via the VESTIBULAR NERVE to the BRAIN STEM. Hair cells in the saccule and those in the utricle sense linear acceleration in vertical and horizontal directions, respectively.Biophysics: The study of PHYSICAL PHENOMENA and PHYSICAL PROCESSES as applied to living things.Sodium Channel Blockers: A class of drugs that act by inhibition of sodium influx through cell membranes. Blockade of sodium channels slows the rate and amplitude of initial rapid depolarization, reduces cell excitability, and reduces conduction velocity.Placental Lactogen: A polypeptide hormone of approximately 25 kDa that is produced by the SYNCYTIOTROPHOBLASTS of the PLACENTA, also known as chorionic somatomammotropin. It has both GROWTH HORMONE and PROLACTIN activities on growth, lactation, and luteal steroid production. In women, placental lactogen secretion begins soon after implantation and increases to 1 g or more a day in late pregnancy. Placental lactogen is also an insulin antagonist.Efferent Pathways: Nerve structures through which impulses are conducted from a nerve center toward a peripheral site. Such impulses are conducted via efferent neurons (NEURONS, EFFERENT), such as MOTOR NEURONS, autonomic neurons, and hypophyseal neurons.Tomography, X-Ray Computed: Tomography using x-ray transmission and a computer algorithm to reconstruct the image.Facial Nerve: The 7th cranial nerve. The facial nerve has two parts, the larger motor root which may be called the facial nerve proper, and the smaller intermediate or sensory root. Together they provide efferent innervation to the muscles of facial expression and to the lacrimal and SALIVARY GLANDS, and convey afferent information for TASTE from the anterior two-thirds of the TONGUE and for TOUCH from the EXTERNAL EAR.Vestibulocochlear Nerve: The 8th cranial nerve. The vestibulocochlear nerve has a cochlear part (COCHLEAR NERVE) which is concerned with hearing and a vestibular part (VESTIBULAR NERVE) which mediates the sense of balance and head position. The fibers of the cochlear nerve originate from neurons of the SPIRAL GANGLION and project to the cochlear nuclei (COCHLEAR NUCLEUS). The fibers of the vestibular nerve arise from neurons of Scarpa's ganglion and project to the VESTIBULAR NUCLEI.Hearing: The ability or act of sensing and transducing ACOUSTIC STIMULATION to the CENTRAL NERVOUS SYSTEM. It is also called audition.Electrophysiology: The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.Bone Conduction: Transmission of sound waves through vibration of bones in the SKULL to the inner ear (COCHLEA). By using bone conduction stimulation and by bypassing any OUTER EAR or MIDDLE EAR abnormalities, hearing thresholds of the cochlea can be determined. Bone conduction hearing differs from normal hearing which is based on air conduction stimulation via the EAR CANAL and the TYMPANIC MEMBRANE.Imaging, Three-Dimensional: The process of generating three-dimensional images by electronic, photographic, or other methods. For example, three-dimensional images can be generated by assembling multiple tomographic images with the aid of a computer, while photographic 3-D images (HOLOGRAPHY) can be made by exposing film to the interference pattern created when two laser light sources shine on an object.Yolk Sac: The first of four extra-embryonic membranes to form during EMBRYOGENESIS. In REPTILES and BIRDS, it arises from endoderm and mesoderm to incorporate the EGG YOLK into the DIGESTIVE TRACT for nourishing the embryo. In placental MAMMALS, its nutritional function is vestigial; however, it is the source of INTESTINAL MUCOSA; BLOOD CELLS; and GERM CELLS. It is sometimes called the vitelline sac, which should not be confused with the VITELLINE MEMBRANE of the egg.Ion Transport: The movement of ions across energy-transducing cell membranes. Transport can be active, passive or facilitated. Ions may travel by themselves (uniport), or as a group of two or more ions in the same (symport) or opposite (antiport) directions.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Gallamine Triethiodide: A synthetic nondepolarizing blocking drug. The actions of gallamine triethiodide are similar to those of TUBOCURARINE, but this agent blocks the cardiac vagus and may cause sinus tachycardia and, occasionally, hypertension and increased cardiac output. It should be used cautiously in patients at risk from increased heart rate but may be preferred for patients with bradycardia. (From AMA Drug Evaluations Annual, 1992, p198)Spinal Fusion: Operative immobilization or ankylosis of two or more vertebrae by fusion of the vertebral bodies with a short bone graft or often with diskectomy or laminectomy. (From Blauvelt & Nelson, A Manual of Orthopaedic Terminology, 5th ed, p236; Dorland, 28th ed)Ions: An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.Hearing Loss, Sudden: Sensorineural hearing loss which develops suddenly over a period of hours or a few days. It varies in severity from mild to total deafness. Sudden deafness can be due to head trauma, vascular diseases, infections, or can appear without obvious cause or warning.Molecular Dynamics Simulation: A computer simulation developed to study the motion of molecules over a period of time.Potassium Channel Blockers: A class of drugs that act by inhibition of potassium efflux through cell membranes. Blockade of potassium channels prolongs the duration of ACTION POTENTIALS. They are used as ANTI-ARRHYTHMIA AGENTS and VASODILATOR AGENTS.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Molecular Docking Simulation: A computer simulation technique that is used to model the interaction between two molecules. Typically the docking simulation measures the interactions of a small molecule or ligand with a part of a larger molecule such as a protein.Allantois: An extra-embryonic membranous sac derived from the YOLK SAC of REPTILES; BIRDS; and MAMMALS. It lies between two other extra-embryonic membranes, the AMNION and the CHORION. The allantois serves to store urinary wastes and mediate exchange of gas and nutrients for the developing embryo.Image Processing, Computer-Assisted: A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.Pituitary Gland, Posterior: Neural tissue of the pituitary gland, also known as the neurohypophysis. It consists of the distal AXONS of neurons that produce VASOPRESSIN and OXYTOCIN in the SUPRAOPTIC NUCLEUS and the PARAVENTRICULAR NUCLEUS. These axons travel down through the MEDIAN EMINENCE, the hypothalamic infundibulum of the PITUITARY STALK, to the posterior lobe of the pituitary gland.Embryo, Mammalian: The entity of a developing mammal (MAMMALS), generally from the cleavage of a ZYGOTE to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the FETUS.Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Lens Capsule, Crystalline: The thin noncellular outer covering of the CRYSTALLINE LENS composed mainly of COLLAGEN TYPE IV and GLYCOSAMINOGLYCANS. It is secreted by the embryonic anterior and posterior epithelium. The embryonic posterior epithelium later disappears.Electrochemistry: The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.Periplasm: The space between the inner and outer membranes of a cell that is shared with the cell wall.Posterior Leukoencephalopathy Syndrome: A condition that is characterized by HEADACHE; SEIZURES; and visual loss with edema in the posterior aspects of the CEREBRAL HEMISPHERES, such as the BRAIN STEM. Generally, lesions involve the white matter (nerve fibers) but occasionally the grey matter (nerve cell bodies).Static Electricity: The accumulation of an electric charge on a objectQuaternary Ammonium Compounds: Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.Decidua: The hormone-responsive glandular layer of ENDOMETRIUM that sloughs off at each menstrual flow (decidua menstrualis) or at the termination of pregnancy. During pregnancy, the thickest part of the decidua forms the maternal portion of the PLACENTA, thus named decidua placentalis. The thin portion of the decidua covering the rest of the embryo is the decidua capsularis.Chorion: The outermost extra-embryonic membrane surrounding the developing embryo. In REPTILES and BIRDS, it adheres to the shell and allows exchange of gases between the egg and its environment. In MAMMALS, the chorion evolves into the fetal contribution of the PLACENTA.Morphogenesis: The development of anatomical structures to create the form of a single- or multi-cell organism. Morphogenesis provides form changes of a part, parts, or the whole organism.Neuroma, Acoustic: A benign SCHWANNOMA of the eighth cranial nerve (VESTIBULOCOCHLEAR NERVE), mostly arising from the vestibular branch (VESTIBULAR NERVE) during the fifth or sixth decade of life. Clinical manifestations include HEARING LOSS; HEADACHE; VERTIGO; TINNITUS; and FACIAL PAIN. Bilateral acoustic neuromas are associated with NEUROFIBROMATOSIS 2. (From Adams et al., Principles of Neurology, 6th ed, p673)Placenta Diseases: Pathological processes or abnormal functions of the PLACENTA.Eye Movements: Voluntary or reflex-controlled movements of the eye.Decerebrate State: A condition characterized by abnormal posturing of the limbs that is associated with injury to the brainstem. This may occur as a clinical manifestation or induced experimentally in animals. The extensor reflexes are exaggerated leading to rigid extension of the limbs accompanied by hyperreflexia and opisthotonus. This condition is usually caused by lesions which occur in the region of the brainstem that lies between the red nuclei and the vestibular nuclei. In contrast, decorticate rigidity is characterized by flexion of the elbows and wrists with extension of the legs and feet. The causative lesion for this condition is located above the red nuclei and usually consists of diffuse cerebral damage. (From Adams et al., Principles of Neurology, 6th ed, p358)Small-Conductance Calcium-Activated Potassium Channels: A major class of calcium-activated potassium channels that are found primarily in excitable CELLS. They play important roles in the transmission of ACTION POTENTIALS and generate a long-lasting hyperpolarization known as the slow afterhyperpolarization.Labyrinth Supporting Cells: Cells forming a framework supporting the sensory AUDITORY HAIR CELLS in the organ of Corti. Lateral to the medial inner hair cells, there are inner pillar cells, outer pillar cells, Deiters cells, Hensens cells, Claudius cells, Boettchers cells, and others.Carboxymethylcellulose Sodium: A cellulose derivative which is a beta-(1,4)-D-glucopyranose polymer. It is used as a bulk laxative and as an emulsifier and thickener in cosmetics and pharmaceuticals and as a stabilizer for reagents.Infratentorial Neoplasms: Intracranial tumors originating in the region of the brain inferior to the tentorium cerebelli, which contains the cerebellum, fourth ventricle, cerebellopontine angle, brain stem, and related structures. Primary tumors of this region are more frequent in children, and may present with ATAXIA; CRANIAL NERVE DISEASES; vomiting; HEADACHE; HYDROCEPHALUS; or other signs of neurologic dysfunction. Relatively frequent histologic subtypes include TERATOMA; MEDULLOBLASTOMA; GLIOBLASTOMA; ASTROCYTOMA; EPENDYMOMA; CRANIOPHARYNGIOMA; and choroid plexus papilloma (PAPILLOMA, CHOROID PLEXUS).Larynx: A tubular organ of VOICE production. It is located in the anterior neck, superior to the TRACHEA and inferior to the tongue and HYOID BONE.Fetal Development: Morphological and physiological development of FETUSES.Posterior Capsule of the Lens: The posterior aspect of the casing that surrounds the natural CRYSTALLINE LENS.Uterus: The hollow thick-walled muscular organ in the female PELVIS. It consists of the fundus (the body) which is the site of EMBRYO IMPLANTATION and FETAL DEVELOPMENT. Beyond the isthmus at the perineal end of fundus, is CERVIX UTERI (the neck) opening into VAGINA. Beyond the isthmi at the upper abdominal end of fundus, are the FALLOPIAN TUBES.Organ Size: The measurement of an organ in volume, mass, or heaviness.Point Mutation: A mutation caused by the substitution of one nucleotide for another. This results in the DNA molecule having a change in a single base pair.Potassium: An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.Ion Channels: Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.Forelimb: A front limb of a quadruped. (The Random House College Dictionary, 1980)Parietal Lobe: Upper central part of the cerebral hemisphere. It is located posterior to central sulcus, anterior to the OCCIPITAL LOBE, and superior to the TEMPORAL LOBES.Hearing Loss: A general term for the complete or partial loss of the ability to hear from one or both ears.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Hearing Loss, Sensorineural: Hearing loss resulting from damage to the COCHLEA and the sensorineural elements which lie internally beyond the oval and round windows. These elements include the AUDITORY NERVE and its connections in the BRAINSTEM.Brain Mapping: Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.Postural Balance: A POSTURE in which an ideal body mass distribution is achieved. Postural balance provides the body carriage stability and conditions for normal functions in stationary position or in movement, such as sitting, standing, or walking.Cations: Positively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis.Body Patterning: The processes occurring in early development that direct morphogenesis. They specify the body plan ensuring that cells will proceed to differentiate, grow, and diversify in size and shape at the correct relative positions. Included are axial patterning, segmentation, compartment specification, limb position, organ boundary patterning, blood vessel patterning, etc.Electrooculography: Recording of the average amplitude of the resting potential arising between the cornea and the retina in light and dark adaptation as the eyes turn a standard distance to the right and the left. The increase in potential with light adaptation is used to evaluate the condition of the retinal pigment epithelium.Embryonic and Fetal Development: Morphological and physiological development of EMBRYOS or FETUSES.Infarction, Posterior Cerebral Artery: NECROSIS induced by ISCHEMIA in the POSTERIOR CEREBRAL ARTERY distribution system which supplies portions of the BRAIN STEM; the THALAMUS; TEMPORAL LOBE, and OCCIPITAL LOBE. Depending on the size and location of infarction, clinical features include OLFACTION DISORDERS and visual problems (AGNOSIA; ALEXIA; HEMIANOPSIA).Nose: A part of the upper respiratory tract. It contains the organ of SMELL. The term includes the external nose, the nasal cavity, and the PARANASAL SINUSES.Kinetics: The rate dynamics in chemical or physical systems.Fetal Death: Death of the developing young in utero. BIRTH of a dead FETUS is STILLBIRTH.Thoracic Vertebrae: A group of twelve VERTEBRAE connected to the ribs that support the upper trunk region.Tetrodotoxin: An aminoperhydroquinazoline poison found mainly in the liver and ovaries of fishes in the order TETRAODONTIFORMES, which are eaten. The toxin causes paresthesia and paralysis through interference with neuromuscular conduction.Neck: The part of a human or animal body connecting the HEAD to the rest of the body.Microscopy, Electron, Scanning: Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.Deglutition: The act of taking solids and liquids into the GASTROINTESTINAL TRACT through the mouth and throat.Gestational Age: The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated as the time from the last day of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization.Computer Simulation: Computer-based representation of physical systems and phenomena such as chemical processes.Reflex: An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.Indicators and Reagents: Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)Lymphatic System: A system of organs and tissues that process and transport immune cells and LYMPH.Cervical Vertebrae: The first seven VERTEBRAE of the SPINAL COLUMN, which correspond to the VERTEBRAE of the NECK.Electric Conductivity: The ability of a substrate to allow the passage of ELECTRONS.Fetal Growth Retardation: The failure of a FETUS to attain its expected FETAL GROWTH at any GESTATIONAL AGE.Mutagenesis: Process of generating a genetic MUTATION. It may occur spontaneously or be induced by MUTAGENS.Extracellular Space: Interstitial space between cells, occupied by INTERSTITIAL FLUID as well as amorphous and fibrous substances. For organisms with a CELL WALL, the extracellular space includes everything outside of the CELL MEMBRANE including the PERIPLASM and the cell wall.Cataract: Partial or complete opacity on or in the lens or capsule of one or both eyes, impairing vision or causing blindness. The many kinds of cataract are classified by their morphology (size, shape, location) or etiology (cause and time of occurrence). (Dorland, 27th ed)Thermodynamics: A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)Mice, Knockout: Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Protein Structure, Secondary: The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Bone Screws: Specialized devices used in ORTHOPEDIC SURGERY to repair bone fractures.Lumbar Vertebrae: VERTEBRAE in the region of the lower BACK below the THORACIC VERTEBRAE and above the SACRAL VERTEBRAE.Deafness: A general term for the complete loss of the ability to hear from both ears.Potassium Channels, Inwardly Rectifying: Potassium channels where the flow of K+ ions into the cell is greater than the outward flow.Posterior Tibial Tendon Dysfunction: A condition characterized by a broad range of progressive disorders ranging from TENOSYNOVITIS to tendon rupture with or without hindfoot collapse to a fixed, rigid, FLATFOOT deformity. Pathologic changes can involve associated tendons, ligaments, joint structures of the ANKLE, hindfoot, and midfoot. Posterior tibial tendon dysfunction is the most common cause of acquired flatfoot deformity in adults.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Fetus: The unborn young of a viviparous mammal, in the postembryonic period, after the major structures have been outlined. In humans, the unborn young from the end of the eighth week after CONCEPTION until BIRTH, as distinguished from the earlier EMBRYO, MAMMALIAN.Cats: The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)Glutamic Acid: A non-essential amino acid naturally occurring in the L-form. Glutamic acid is the most common excitatory neurotransmitter in the CENTRAL NERVOUS SYSTEM.Lysine: An essential amino acid. It is often added to animal feed.Porosity: Condition of having pores or open spaces. This often refers to bones, bone implants, or bone cements, but can refer to the porous state of any solid substance.Orientation: Awareness of oneself in relation to time, place and person.Protein Subunits: Single chains of amino acids that are the units of multimeric PROTEINS. Multimeric proteins can be composed of identical or non-identical subunits. One or more monomeric subunits may compose a protomer which itself is a subunit structure of a larger assembly.Gene Targeting: The integration of exogenous DNA into the genome of an organism at sites where its expression can be suitably controlled. This integration occurs as a result of homologous recombination.PrimatesCadaver: A dead body, usually a human body.Cell Membrane Permeability: A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.
... or veins of labyrinth) which end in the posterior part of the superior petrosal sinus or in the transverse sinus. This article ... The veins of the vestibule and semicircular canals accompany the arteries, and, receiving those of the cochlea at the base of ...
The posterior canal is part of the bony labyrinth and is used by the vestibular system to detect rotations of the head in the ... The cochlea and vestibule, viewed from above. Transverse section through head of fetal sheep, in the region of the labyrinth. X ... which opens into the upper and medial part of the vestibule. The posterior semicircular canal is a part of the vestibular ... The semicircular canals are a component of the bony labyrinth. At one end of each of the semicircular canals is a dilated sac ...
At the hinder part of the medial wall of the vestibule is the orifice of the vestibular aqueduct, which extends to the ... The diagnosis can be made by high resolution CT or MRI, with comparison to the adjacent posterior semicircular canal. If the ... It transmits a small vein, and contains a tubular prolongation of the membranous labyrinth, the ductus endolymphaticus, which ... posterior surface of the petrous portion of the temporal bone. ...
The vestibule is the central part of the bony labyrinth in the inner ear, and is situated medial to the eardrum (tympanic ... The orifice of the aquæductus vestibuli is the hind part of the medial wall; it extends to the posterior surface of the petrous ... Right osseous labyrinth (lateral view). The cochlea and vestibule (view from above). Chain of ossicles and their ligaments, ... Vestibule visible at center right.) Internal liquid structures of the cochlea and semicircular ducts, vestibule at centre. This ...
The vestibule of the ear is the central part of the inner ear labyrinth, as used in the vestibular system *The ... The vulval vestibule is the posterior 2/3 of the labia minora, the location of the urethral meatus and the paraurethral glands ... Look up vestibule in Wiktionary, the free dictionary.. Vestibule or Vestibulum can have the following meanings, each primarily ... The vestibule of larynx is between the epiglottis and rima glottidis. *The aortic vestibule is the part of the left ventricle ...
The bony labyrinth refers to the bony compartment which contains the membranous labyrinth, contained within the temporal bone. ... The posterior auricular artery is a direct branch of the external carotid artery, and the anterior auricular arteries are ... A central area known as the vestibule contains two small fluid-filled recesses, the utricle and saccule. These connect to the ... The posterior auricular artery provides the majority of the blood supply. The anterior auricular arteries provide some supply ...
... vestibule is a small space or cavity at the beginning of a canal. The vulval vestibule is the posterior 2/3 of the labia minora ... which is lined with respiratory epithelium The vestibule of the ear is the central part of the inner ear labyrinth, as used in ... Vestibule or Vestibulum can have the following meanings, each primarily based upon a common origin, from early 17th century ... rima glottidis The aortic vestibule is the part of the left ventricle of the heart just below the aortic valve The vestibule of ...
The posterior canal is part of the bony labyrinth and is used by the vestibular system to detect rotations of the head in the ... Its ampullated end corresponds to the upper and lateral angle of the vestibule, just above the oval window, where it opens ... Posterior semicircular canalEdit. The posterior semicircular canal is a part of the vestibular system that detects rotation of ... The semicircular canals are a component of the bony labyrinth. At one end of each of the semicircular canals is a dilated sac ...
It is part of the neural ectoderm, which will develop into the membranous labyrinth of the inner ear. This labyrinth is a ... The central part of the otic vesicle represents the membranous vestibule, and is subdivided by a constriction into a smaller ... ventral part, the saccule, and a larger dorsal and posterior part, the utricle. The dorsal component of the inner ear also ... Lateral views of membranous labyrinth and acoustic complex. X 25 dia. Median views of membranous labyrinth and acoustic complex ...
The ethmoidal sinuses are further subdivided into anterior and posterior ethmoid sinuses, the division of which is defined as ... it is below this level and sometimes level with the vestibule or nasal entrance. Acute sinusitis is usually precipitated by an ... ethmoidal veins thrombophlebitis enables the spread of the infection to the lateral or orbital side of the ethmoid labyrinth. ... The cause of this situation is usually a periapical or periodontal infection of a maxillary posterior tooth, where the ...
The posterior group (sometimes the posterior ethmoidal sinus) drains into the superior meatus above the middle nasal concha; ... The ethmoidal air cells consist of numerous thin-walled cavities situated in the ethmoidal labyrinth and completed by the ... The ethmoidal air cells receive sensory fibers from the anterior and posterior ethmoidal nerves, and the orbital branches of ... Nasal vestibule. *Nostril. *Posterior nasal apertures. Lateral wall. *Nasal conchae: Supreme nasal concha ...
Vestibular labyrinth. Static/translations/vestibule/endolymphatic duct: Utricle (Macula) · Saccule (Macula, Endolymphatic sac) ... Kinetic/rotations: Semicircular canals (Superior, Posterior, Horizontal) • Ampullary cupula • Ampullae (Crista ampullaris) ... Posterior ligament of incus) · Stapes (Anular ligament of stapes) ...
To the front of the nasal cavity is the nasal vestibule and external opening, while the back blends, via the choanae, into the ... The nasal cavity also houses the sense of smell and contributes greatly to taste sensation through its posterior communication ... the labyrinth of ethmoid and the inferior concha. The paranasal sinuses are connected to the nasal cavity through small ... Anterior ethmoidal artery and posterior ethmoidal artery, branches of the ophthalmic artery Septal Branches of the superior ...
The inside of the ear is composed of an organ called the vestibular labyrinth. The vestibular labyrinth includes semicircular ... It involves a reorientation of the head to align the posterior semicircular canal (at its entrance to the ampulla) with the ... Treatment is therefore geared towards moving the canalith from the lateral canal into the vestibule. The roll maneuver or its ... Within the labyrinth of the inner ear lie collections of calcium crystals known as otoconia or otoliths. In patients with BPPV ...
Vestibular labyrinth. Vestibule. *Utricle *macula. *Saccule *macula. *Kinocilium. *Otolith. *Vestibular aqueduct *endolymphatic ... posterior auricular, anterior auricular. Nerve. Trigeminal nerve, Great auricular nerve, Lesser occipital nerve. ...
... also known as the anterior transverse temporal area 41 and the posterior transverse temporal area 42, respectively. Both areas ... Vestibular labyrinth. Vestibule. *Utricle *macula. *Saccule *macula. *Kinocilium. *Otolith. *Vestibular aqueduct *endolymphatic ...
posterior part: posterior auricular artery. Vein. superficial temporal veins, external jugular vein, pterygoid plexus. ... Vestibular labyrinth. Vestibule. *Utricle *macula. *Saccule *macula. *Kinocilium. *Otolith. *Vestibular aqueduct *endolymphatic ...
Vestibular labyrinth. Vestibule. *Utricle *macula. *Saccule *macula. *Kinocilium. *Otolith. *Vestibular aqueduct *endolymphatic ...
... fragile pars flaccida lies above the lateral process of the malleus between the notch of Rivinus and the anterior and posterior ... Vestibular labyrinth. Vestibule. *Utricle *macula. *Saccule *macula. *Kinocilium. *Otolith. *Vestibular aqueduct *endolymphatic ...
Short posterior ciliary arteries Long posterior ciliary arteries Supra-orbital artery Anterior ethmoidal artery Posterior ... Mons pubis Labium majus Pudendal cleft Labium minus Vestibule of vagina Bulb of vestibule Greater vestibular gland Clitoris ... see bones Perilymphatic space Membranous labyrinth Endolymphatic space Vestibular labyrinth Utricle Saccule Semicircular ducts ... Levator scapulae Serratus posterior inferior Serratus posterior superior Anterior cervical intertransversarii Lateral posterior ...
... posterior inferior cerebellar artery posterior lobe of the cerebellum posterior nasal artery posterior septal artery posterior ... labia majora labia minora labium labrum labyrinth lacrimal bone lacrimal canaliculus lacrimal fossa lacrimal gland lacrimal ... system vertigo vesicle vesiculae seminales vestibular folds vestibular ganglion vestibular membrane vestibular nuclei Vestibule ... membrane posterior auricular artery posterior cerebral artery Posterior chamber of eyeball posterior clinoid posterior column- ...
The HINTS exam as well as imaging studies of the brain (CT, CT angiogram, and/or MRI) are helpful in diagnosis of posterior ... the vestibule (utricle and saccule), and the vestibular nerve is called "peripheral", "otologic" or "vestibular" vertigo. The ... and vasospasm of the blood vessels supplying the labyrinth or central vestibular pathways resulting in ischemia to these ... A stroke (either ischemic or hemorrhagic) involving the posterior fossa is a cause of central vertigo. Risk factors for a ...
A third (pterotic) roofs in the tympanic cavity and antrum; while the fourth (epiotic) appears near the posterior semicircular ... vestibule, superior semicircular canal, and medial wall of the tympanic cavity. A second (opisthotic) appears at the promontory ... but occurs more at its anterior and posterior portions. As these outgrowths meet, they create a foramen in the floor of the ... it forms the floor of the tympanic cavity and vestibule, surrounds the carotid canal, invests the lateral and lower part of the ...
The vestibule is the region of the inner ear where the semicircular canals converge, close to the cochlea (the hearing organ). ... are working to understand the various balance disorders and the complex interactions between the labyrinth, other balance- ... Vitamin B12 deficiency CNS or posterior neoplasms, benign or malignant Neurological: Vertiginous epilepsy, abasia Other - There ...
A stroke (either ischemic or hemorrhagic) involving the posterior fossa is a cause of central vertigo.[32] Risk factors for a ... the vestibule (utricle and saccule), and the vestibular nerve is called "peripheral", "otologic" or "vestibular" vertigo.[15][ ... and vasospasm of the blood vessels supplying the labyrinth or central vestibular pathways resulting in ischemia to these ... are helpful in diagnosis of posterior fossa stroke.[32] ... surgical measures such as a shunt or ablation of the labyrinth ...
The posterior canal is part of the bony labyrinth and is used by the vestibular system to detect rotations of the head in the ... Its ampullated end corresponds to the upper and lateral angle of the vestibule, just above the oval window, where it opens ... Posterior semicircular canalEdit. The posterior semicircular canal is a part of the vestibular system that detects rotation of ... The semicircular canals are a component of the bony labyrinth that are at right angles from each other. At one end of each of ...
Vestibule, Labyrinth / physiology. From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine ... Cranial Fossa, Posterior*. Electric Stimulation / methods. Electromyography / methods. Evoked Potentials, Motor / physiology. ... The tremor was reset by electrical stimulation over the posterior fossa at intensities that were below the threshold for a ...
How does the vestibule of the inner ear open posterolateral to the IAM in the posterior petrous part of the temporal bone? ... What provides arterial supply to the bony labyrinth of the inner ear? ... Anterior, posterior and lateral lie posterosuperior to the vestibule and at right angles to each other with bony swellings ( ... How is the vestibule of the inner ear continuous with the posterior cranial fossa? ...
narrow channel running through the vitreous body from the optic disc to the posterior surface of the lens ... ocal yellowisharea at the center of the posterior part of the retina, area for most distinct vision ... the aqeous humor flows from the psoterior chamber into the posterior chamber via the ... ciliary body > cleft of posterior chamber > pupil > anterior chamber > trabecular meshwork > Schlemm @ iridocorneal angle ...
... bony labyrinths explanation free. What is bony labyrinths? Meaning of bony labyrinths medical term. What does bony labyrinths ... Looking for online definition of bony labyrinths in the Medical Dictionary? ... Labyrinth. (A), Anterior view of the bony labyrinth (labyrinthus osseus). (B), Posterior view of the membranous labyrinth ( ... labyrinth. [lab´ĭ-rinth] the inner ear, consisting of the vestibule, cochlea, and semicircular canals. The cochlea is concerned ...
The vestibule is the central part of the bony labyrinth in the inner ear, and is situated medial to the eardrum (tympanic ... The orifice of the aquæductus vestibuli is the hind part of the medial wall; it extends to the posterior surface of the petrous ... Right osseous labyrinth (lateral view). The cochlea and vestibule (view from above). Chain of ossicles and their ligaments, ... Vestibule visible at center right.) Internal liquid structures of the cochlea and semicircular ducts, vestibule at centre. This ...
... or veins of labyrinth) which end in the posterior part of the superior petrosal sinus or in the transverse sinus. This article ... The veins of the vestibule and semicircular canals accompany the arteries, and, receiving those of the cochlea at the base of ...
The inner ear is called the labyrinth and has three basic parts, the vestibule, the semicircular canals and the cochlea. Two ... The semicircular canals are called lateral, superior and posterior canals. Each duct widens and forms a pouch called the ... baglike sacs called the utricle and the saccule are found in the vestibule and each is lined with hair cells. Hair cells are ...
semicircular canals three long canals (anterior, lateral, and posterior) of the bony labyrinth, important in the sense of ... posterior, and lateral) that open into the vestibule. They are enclosed within the petrous portion of the temporal bone. ... the canals (anterior, lateral and posterior) of the bony labyrinth of the ear. See also semicircular canals. ... that extend from the vestibule of the labyrinth in the inner ear. The semicircular canals are the bony shells that contain the ...
The height of the vertex of the posterior canal above the vestibule is 5 mm. and the diameter of the canal itself at the vertex ... The labyrinth measures 10 mm. in extreme length from the outermost point on the posterior canal to the innermost point on the ... The whole labyrinth measures 8 mm. in length from the outermost point on the vertex of the posterior canal to the innermost ... 2. Membranous Labyrinth of the Indian Gazelle, Gazella Bennetti.. Fig. 3. Membranous Labyrinth of the Three-toed Sloth, ...
Additionally, the plane of the lateral (horizontal) semicircular canal of the bony labyrinth is oriented nearly vertically if ... is found immediately posterior to the bony labyrinth (Fig. 3B). There is a clear osseous separation between the vestibule of ... Bony labyrinth and head posture. The bony labyrinth in Moschops is very unusual amongst NMT because compared to other NMT in ... Bony labyrinth. The right side of the braincase is best preserved in AM4950, but the bony labyrinth is complete only on the ...
The vestibule of the ear is the central part of the inner ear labyrinth, as used in the vestibular system *The ... The vulval vestibule is the posterior 2/3 of the labia minora, the location of the urethral meatus and the paraurethral glands ... Look up vestibule in Wiktionary, the free dictionary.. Vestibule or Vestibulum can have the following meanings, each primarily ... The vestibule of larynx is between the epiglottis and rima glottidis. *The aortic vestibule is the part of the left ventricle ...
The bony cochlea lies in countenance of the vestibule Vestibule and is like a snail fa‡ade. On its fourth turns, coiling ... Membranous Labyrinth ted and is called the ampulla which houses the The membranous labyrinth is filled with vestibular receptor ... The posterior semicircu- The inner attention is a character of winding pas- lar canal lies in a level parallel to the derriere ... The triangle is completed on a line which is medial bulwark of the antrum is formed away the besides the point to the posterior ...
A calcareous concretion in the posterior semicircular duct of a human labyrinth. / Wright, Charles G.; Rouse, Roland C.; Zajic ... A calcareous concretion in the posterior semicircular duct of a human labyrinth. American Journal of Otolaryngology--Head and ... Fingerprint Dive into the research topics of A calcareous concretion in the posterior semicircular duct of a human labyrinth ... title = "A calcareous concretion in the posterior semicircular duct of a human labyrinth", ...
What is the labyrinth and what does it do?. The labyrinth is in the inner ear. The inner ear includes the cochlea, vestibule ... There are three semicircular canals (anterior, lateral and posterior). These are roughly at right angles to each other and ... What is the labyrinth and what does it do? * ... What is the labyrinth and what does it do? * What is vestibular ... These are small shell-like structures in which there is a system of narrow fluid-filled channels called the labyrinth. The ...
The bony labyrinth refers to the bony compartment which contains the membranous labyrinth, contained within the temporal bone. ... The posterior auricular artery provides the majority of the blood supply. The anterior auricular arteries provide some supply ... A central area known as the vestibule contains two small fluid-filled recesses, the utricle and saccule. These connect to the ... The posterior auricular artery is a direct branch of the external carotid artery, and the anterior auricular arteries are ...
is designed to relocate the free-floating debris from the posterior canal to the vestibule of the vestibular labyrinth. Severe ... The Dix-Hallpike maneuver, which tests for canaliths in the posterior semi-circular canal, should be performed when BPPV is ... Vertigo arises from damage to or dysfunction of the labyrinth, vestibular nerve, or central vestibular structures in the ... as it is more sensitive early for stroke and for detecting stenosis or occlusion of the posterior circulation. CT scanning is ...
APSC - Ampulla of posterior semicircular canal FIAC - Fundus of IAC C - Crus commune inner opening V - Vestibule AL - Ampulla ... The apulla of PSS is opened in to postero inferior part of vestibule opposite to crus commune in posterior recess of the ... Retrotympanum is posterior part of the middle ear cavity behind the annulus tympanicus.. The prominent reference point in ... After its origin 2 mm medial to fundus of IAC, it passes through singular foramen, present at posterior wall of IAC to come out ...
Finally, the bony vestibule of CBI-1-542 displays a secondary common crus where the posterior limb of the lateral canal and the ... Bony Labyrinth (Fig. 3). The digitally-reconstructed cast of the bony labyrinth is almost complete. The cochlear canal makes ... On the contrary, orientation of the bony labyrinth was simplified: the anterior view of the bony labyrinth is orthogonal to the ... a bony vestibule clearly less voluminous than the cochlear canal (23(1); CI = 0.5), a bony labyrinth having its three ...
The posterior canal is part of the bony labyrinth and is used by the vestibular system to detect rotations of the head in the ... Its ampullated end corresponds to the upper and lateral angle of the vestibule, just above the oval window, where it opens ... Posterior semicircular canalEdit. The posterior semicircular canal is a part of the vestibular system that detects rotation of ... The semicircular canals are a component of the bony labyrinth. At one end of each of the semicircular canals is a dilated sac ...
vision(photoreceptors) hearing(mechanoreceptors) balance/equilibrium(mechanoreceptors)(located vestibule and semicircular ... the posterior cavity(chamber) behind the lens. auricle. (pinna outside part) flappy exterior of ear. ... water fluid in the bony labyrinth. perilymph. endolymph. which is inside cochlea and semicircular canals. ...
The bony labyrinth forms 3 semicircular canals, the cochlea, and an ovaluar chamber called the vestibule. This bony shell is ... The posterior semicircular duct, the saccule, and a small part of the utricle are supplied by the posterior vestibular artery. ... The anterior and posterior canals are oriented 45 degrees lateral to the sagittal plane, such that the posterior and anterior ... Bony Labyrinth. The peripheral vestibular system consists of a bony and membranous labyrinth.[2] ...
Inner ear/Labyrinth. Bony labyrinth (Vestibule) • Membranous labyrinth. Oval window • Helicotrema • Round window. Cochlea: ... Conjoined limb of superior and posterior canals (sinus utriculi superior).. *Utricle. 5. Recessus utriculi. 5". Sinus utriculi ... For more uses of the word labyrinth, see Labyrinth (disambiguation). The labyrinth is a system of fluid passages in the inner ... The vestibule is the region of the inner ear where the semicircular canals converge, close to the cochlea (the hearing organ). ...
The vestibular labyrinth is made up of three semicircular canals - lateral, posterior and superior. They join together at the ... Inner ear balance organ: vestibule, semicircular canals, cochlea and audio-vestibular nerve ... As well as the cochlea for hearing, the inner ear contains a very sensitive organ, the vestibular labyrinth, designed to help ... The commonest condition to affect the inner ear is labyrinthitis, which means inflammation of the labyrinth and causes severe ...
The posterior portion of the bony labyrinth contains the vestibule and the semicircular canals, and is responsible for ... It consists of a bony shell (the bony labyrinth) within which is found the membranous labyrinth-a series of cavities forming a ... The membranous labyrinth is separated from the bony labyrinth by the perilymph, a sodium-rich liquid. ... which lines the posterior chamber. The posterior chamber is filled with the vitreous humour-a clear, gelatinous liquid. The ...
The osseous labyrinth has three regions, the vestibule, the semicircular canals and the cochlea. The membranous labyrinth can ... The stapedius muscle extends from the wall of a conical cavity in the pyramidal eminence, located on the posterior wall of the ... The inner ear comprises the osseous labyrinth and the contained membranous labyrinth. ... The faceplate of the stapes rests against the membranous labyrinth in the opening of the oval window, where sound waves are ...
  • Its lower or ampullated end opens into the lower and back part of the vestibule, its upper into the crus commune . (wikipedia.org)
  • Our ideas of the anatomy of the labyrinth have depended so much upon the investigation of the organ in the human subject that it is not surprising that errors have crept in by assuming that certain features found in him will also be found in the lower animals. (edu.au)
  • Anatomy of the labyrinth. (medscape.com)
  • It is directed superiorly, as per its nomenclature, and posteriorly, nearly parallel to the posterior surface of the petrous bone . (wikipedia.org)