Infobox Anatomy Name Utricle ear Latin utriculus GraySubject 232 GrayPage 1051 Image bigotolith.jpg Caption illustration of otolith organs showing detail of Utricle ear utricle , otoconia , endolymph , cupula , macula , hair cell filaments, and saccular nerve Map Inner ear map MapCaption Components of the inner ear including the utricle MapPos Utricle ear System MeshName Saccule and Utricle MeshNumber A09.246.631.909.625 DorlandsPre u 04 DorlandsSuf 12841370 The utricle , or utriculus, along with the saccule is one of the two otolith organs located in the vertebrate inner ear . The utricle and the saccule are parts of the balancing apparatus membraneous labyrinth located within the vestibule of the bony labyrinth small oval chamber . ref Moores, Kieth L. Essential Clinical Anatomy Lippincott Williams & Wilkins Second Edition edition 2002 . ref These use small stones and a viscous fluid to stimulate hair cells to detect motion and orientation. Anatomy The utricle is larger than the saccule and is of an oblong form, compressed transversely, and occupies the upper and back part of the Vestibule of the ear vestibule , lying in contact with the recessus ellipticus and the part below it. The utricle contains mechanoreceptors called hair cells that distinguish between degrees of tilting of the head, thanks to their apical stereocilia set up. These are covered by otolith which, due to gravity, pull on the stereocilia and tilt them. Depending on whether the tilt is in the direction of the kinocilium or not, the resulting hair cell polarisation is excitatory depolarising or inhibitory hyperpolarisation , respectively. Any orientation of the head causes a combination of stimulation to the utricles and saccules of the two ears. The brain interprets head orientation by comparing these inputs to each other and to other input from the eyes and stretch receptors in the neck, thereby detecting whether only the head is tilted or the entire body is tipping. The inertia of the otolithi ... more details
Multiple issues unreferenced November 2009 expert subject November 2008 cleanup November 2007 Drop attacks are sudden spontaneous falls while Standing position standing or walking , followed by a very swift recovery, within seconds or minutes. See also Atonic seizure Causes Drop attacks are typically seen in elderly patients, and the most common cause is carotid sinus hypersensitivity, resulting in either short periods of reversible asystole , or in marked drop in blood pressure in response to carotid sinus stimulation. Other causes include the following vascular transient ischemic attack , cerebrovascular accident , dissection, occlusion, hemorrhage intracranial hematoma posterior circulation infarction , emboli, vasospasm bilateral anterior circulation occlusion migraine accompagnee develop over 1hr with assoc paresthesia , HA basilar artery insuff older pt with no LOC, transient loss of LE tone epilepsy paroxysmal neurally mediated syncope 75 of all causes Atonic seizure Lennox Gastaut syndrome atonic, myoclonic, GTC typically in neuro abnormal pt Juvenile myoclonic epilepsy Juvenile Myoclonic Epilepsy fall with myoclonus cataplexy associated with narcolepsy periodic paralyses complex partial seizure breath holding spells associate pallor cyanosis , emotional aspect pure autonomic failure Riley Day , long standing DM episodic ataxia Panayiotopoulos syndrome degenerative postural instability with Parkinsons structural chronic odontoid instability spinal cord trauma with transient paraplegia brainstem mass metabolic hypoglycemia , hypocalcemia , Hypomagnesemia toxins , drugs cocaine , sedatives , antihistamine , TCA cardiac prolonged QT, tachycardia , bradycardia , sick sinus syndrome , Cardiac arrhythmia arrhythmia , IHSS. AS hypovolemia psychiatric malingering, conversion, panic , anxiety labyrinth hydrops an overflow of endolymph in ear labyrinth causes distortions and breaks see also M ni re s syndrome Diagnosis important if there was an inciting event NMS, bre ... more details
Ernst Julius Richard Ewald 14 February 1855 22 July 1921 was a German physiologist born in Berlin . He was a younger brother to gastroenterologist Carl Anton Ewald 1845 1915 . In 1880, after finishing his studies in mathematics , physics and medicine, he became an assistant to physiologist Friedrich Goltz 1834 1902 at the University of Strasbourg . In 1900 he succeeded Goltz as chair of physiology at Strasbourg , a position he maintained until 1918. Ewald is best remembered for his research of the vestibular system of the inner ear , largely involving experiments performed on the semicircular canal semicircular canal system of pigeons . From these studies the so called Ewald laws are derived, which deal with the effects of endolymph motion on body, head and eye movements and also the phenomena of excitation inhibition asymmetries in the vestibular system. ref http www.med.uvm.edu surgery downloads COCLIA Vestibular2.pdf COCLIA Vestibular ref Ewald s first law The axis of nystagmus parallels the anatomic axis of the semicircular canal that generated it . Ewald s second law Ampullopetal endolymphatic flow produces a stronger response than ampullofugal flow in the horizontal canal . ref http www.vestibularseminars.com images Vestibular Glossary.doc Vestibular Glossary ref In 1892 he was awarded by the Paris Academy of Sciences for the monograph Physiologische Untersuchungen ber das Endorgan des Nervus octavus . Selected writings Physiologische Untersuchungen ber das Endorgan des Nervus octavus 1892 . Ist die Lunge luftdicht? with Rudolf Kobert . Zur Physiologie des Labyrinths 1895 physiology of the labyrinth inner ear labyrinth . Die Physiologie des Kehlkopfs 1896 physiology of the larynx . Eine neue H rtheorie 1899 new theory of hearing. Schallbildertheorie und Erkenntnistheorie , Z. Sinnesphysiol. 53, 213 217. 1914 theory of sound patterns and epistemology . References http www.deutsche biographie.de sfz13908.html Deutsche Biographie biography reflist List of publi ... more details
also gives rise to the cochlear duct , which contains the spiral organ of Corti and the endolymph ... by the spiral ligament and the stria vascularis , which produces the endolymph . The hair cells ... parallel with the perilymphatic duct is a separate blind ending duct, the lagena , filled with endolymph ... more details
viscosity of the blood and the endolymph during the consumption of alcohol. The common term ... than in the vestibular system, hence the endolymph is relatively dense. PAN II The alcohol concentration is lower in the blood than in the vestibular system, hence the endolymph is relatively dilute ... more details
chambers is perilymph , while scala media, or the cochlear duct , is filled with endolymph . ref ... occur in the endolymph that bathes the apical ends of the hair cells. These MET channels are interconnected ... concentration while the endolymph found in the scala media has a high potassium concentration ... more details
Body fluid , bodily fluids , or biofluids are liquid s originating from inside the human body bodies of living people . They include fluids that are excretion excreted or secretion secreted from the body as well as body water that normally is not. The dominating content of body fluids is animal body water body water . Approximately 60 65 of body water is contained within the cells in intracellular fluid with the other 35 40 of body water contained outside the cells in extracellular fluid . This fluid component outside of the cells include the fluid between the cells interstitial fluid , lymph and blood . There are approximately 6 to 10 liters of lymph in the body, compared to 3.5 to 5 liters of blood. ref www.diagnose me.com cond C162576.html Lymphatic Congestion ref Body fluids include columns list 3 Amniotic fluid Aqueous humour and vitreous humour Bile Blood serum Breast milk Cerebrospinal fluid Cerumen earwax Endolymph and perilymph Female ejaculate Gastric juice Mucus including nasal drainage and phlegm Peritoneal fluid Pleural fluid Saliva Sebaceous gland Sebum skin oil Semen Sweat Tears Vaginal lubrication Vaginal secretion Vomit Urine Body fluids and health Body fluid is the term most often used in medical and health contexts. Modern medical , public health , and personal hygiene practices treat body fluids as potentially unclean. This is because they can be Vector epidemiology vector s for infectious diseases, such as sexually transmitted disease s or blood borne disease s. Universal precautions and safer sex practices try to avoid exchanges of body fluids. Body fluids can be analysed in medical laboratory in order to find microbes, inflammation, cancers, etc. Sampling Methods of sampling medicine sampling of body fluids include Blood sampling for any blood test , in turn including Artery Arterial blood sampling, such as radial artery puncture Venous blood sampling, also called venipuncture Lumbar puncture to sample cerebrospinal fluid Thoracocentesis to sa ... more details
Infobox Anatomy Name Saccule Latin sacculus GraySubject 232 GrayPage 1052 Image Bigotolith.jpg Caption illustration of otolith organs showing detail of Utricle ear utricle , otoconia , endolymph , cupula , macula , hair cell filaments, and saccular nerve Image2 Caption2 Map Inner ear map MapPos Saccule System MeshName Saccule and Utricle MeshNumber A09.246.631.909.625 Saccular Acoustic Sensitivity is a measurement of the ear s affectability to sound. The saccule s normal function is to keep the body balanced, but it is believed to have some hearing function for special frequencies and tones . Saccular acoustic sensitivity is considered to be simply an extension of the sense of hearing through the use of the saccule. Effects Saccular acoustic sensitivity has a variety physiological as well as mental emotional effects. Physical Effects Perhaps the most observable physical response is goose bumps . A similar effect is the manifestation of chills . Some sounds have been known to cause reflexive muscle movements like a twitch or even a jump. ref Eckart Altenm ller, et al. Chills In Different Sensory Domains Frisson Elicited By Acoustical, Visual, Tactile And Gustatory Stimuli. Psychology Of Music 39.2 2011 220 239. PsycINFO. Web. 12 Dec. 2011. ref Since these physical effects are easily recorded and are linked consistently with strong emotion, they have bee used in several types of psychological studies. ref McCrae, Robert R. Aesthetic Chills as a Universal Marker of Openness to Experience. Motivation and Emotion 31.1 2007 5 11. Print. ref Mental Emotional Effects Certain sounds, such as fingernails drawn down a blackboard , cause strong feelings of aversion or even fear in most humans. A 2004 study claimed that the blackboard sound was very similar to the warning cry of Siamang gibbons and hypothesized that a vestigial reflex is what causes the fight or flight reaction in humans. ref Todd, Neil P. McAngus, and Merker, Bjorn. Siamang Gibbons Exceed the Saccular Threshold ... more details
. Strikingly, one section, called the cochlear duct or scala media , contains endolymph , a fluid ... fluid. The chemical difference between the two fluids endolymph & perilymph is important ... more details
of Alcohol, citizendia.org. ref Alcohol affects balance by changing the viscosity of the endolymph within the otolithic membrane, the fluid inside the semicircular canals inside the ear. The endolymph ..., the endolymph flows and moves the cupula. The hair cells then bend and send signals to the brain indicating the direction in which the head is tilted. By changing the viscosity of the endolymph ... more details
, and each of the six canals encloses a membranous duct that forms an endolymph filled circuit. Hair cells in the duct s auditory ampulla pick up endolymph disturbances caused by movement, which register ... more details
canal causes abnormal pathological fluid endolymph displacement and a resultant sensation of vertigo ... endolymph. Upon reorientation of the head relative to gravity, the cupula is weighted down by the dense ... more details
Infobox Anatomy Name Otolith Latin GraySubject 232 GrayPage 1054 Image bigotolith.jpg Caption Otolith organs showing detail of utricle, otoconia, endolymph, cupula, macula, hair cell filaments, and saccular nerve Image2 Herringjuvenilekils.jpg Caption2 Juvenile herring . Length 30 mm 3 months old still transparent the otoliths are visible left of the eye. System MeshName Otolithic Membrane MeshNumber A09.246.631.909.625.125.680 An otolith , , oto , ear , lithos , a stone , also called statoconium or otoconium is a structure in the saccule or Utricle ear utricle of the inner ear , specifically in the Labyrinth inner ear vestibular labyrinth of vertebrates. The saccule and utricle, in turn, together make the otolith organs . They are sensitive to gravity and linear acceleration . Because of their orientation in the head, the Utricle ear utricle is sensitive to a change in horizontal movement, and the saccule gives information about vertical acceleration such as when in an elevator . Description Endolymphatic infillings such as an otolith , , oto , ear , lithos , a stone or statoconia are structures in the saccule or Utricle ear utricle of the inner ear , specifically in the Labyrinth inner ear vestibular labyrinth of all vertebrates fish, amphibians, reptiles, mammals and birds . In vertebrates the saccule and utricle together make the otolith organs . Both statoconia and otoliths are used as gravity, balance, movement, and directional indicators in all vertebrates and have a secondary function in sound detection in higher aquatic and terrestrial vertebrates. ref name SheykholeslamiKaga2002 cite journal last1 Sheykholeslami first1 Kianoush last2 Kaga first2 Kimitaka title The otolithic organ as a receptor of vestibular hearing revealed by vestibular evoked myogenic potentials in patients with inner ear anomalies journal Hearing Research volume 165 issue 1 2 year 2002 pages 62 67 issn 03785955 doi 10.1016 S0378 5955 02 00278 2 ref ref name JonesLukash ... more details
Noise induced hearing loss NIHL is an increasingly prevalent disorder that results from exposure to high intensity sound , especially over a long period of time. Description NIHL is a preventable hearing disorder that affects people of all ages and demographics. Mechanism NIHL occurs when too much sound intensity is transmitted into and through the auditory system . An acoustic signal from an energy source, such as a radio, enters into the external auditory canal , and is funneled through to the tympanic membrane eardrum . The tympanic membrane acts as an elastic diaphragm and drives the ossicular chain of the middle ear system into motion. Then the middle ear ossicles transfer mechanical energy to the cochlea by way of the Middle ear bone complex Ossicles stapes footplate hammering against the oval window of the cochlea. This hammering causes the fluid within the cochlea perilymph and endolymph to push against the stereocilia of the hair cells, which then transmit a signal to the central auditory system within the brain. When the ear is exposed to excessive sound levels or loud sounds over time, the overstimulation of the hair cells leads to heavy production of reactive oxygen species, leading to oxidative cell death. In animal experiments, antioxidant vitamins have been found to reduce hearing loss even when administered the day after noise exposure. ref Yamasoba, T. et al. http www.sciencedirect.com science? ob ArticleURL& udi B6SYR 3WBG210 B& user 10& rdoc 1& fmt & orig search& sort d&view c& version 1& urlVersion 0& userid 10&md5 1178013205fe4ed07e720ae2a2503d1c Role of glutathione in protection against noise induced hearing loss . Brain Research ref They were not able to fully prevent it. quote Some of the abnormalities include metabolic exhaustion of the hair cells, structural changes and degeneration of structures within the hair cells, morphological changes of the cilia, ruptures of cell membranes, and complete degeneration and loss of hair cells, neural ce ... more details
Encyclopedia
top
