Uvea

For the island and chiefdom in Wallis & Futuna, see Wallis (island) and Uvea (Wallis and Futuna).
For the island and municipality in New Caledonia, see Ouvéa Island and Ouvéa.
For the languages, see East Uvean and West Uvean.
Uvea
Graphical representation of an eyeball. The constituents of the uvea follow: iris (labeled as 9), ciliary body (labeled as 3), and choroid (labeled as 28.)
Horizontal section of the eyeball. The constituents of the uvea follow: iris labeled at top, ciliary body labeled at upper right, and choroid labeled at center right.)
Details
Part ofThe human eye
SystemSensory nervous system
LocationLies between the corneosclera (outermost layer of the eye) and the retina (innermost layer/in the back of the eye
Identifiers
Latintunica vasculosa bulbi
MeSHD014602
TA98A15.2.03.001
TA26752
FMA58103
Anatomical terminology

The uvea (/ˈjuːviə/;[1] derived from Latin: uva meaning "grape"), also called the uveal layer, uveal coat, uveal tract, vascular tunic or vascular layer, is the pigmented middle layer of the three concentric layers that make up an eye, precisely between the inner retina and the outer fibrous layer composed of the sclera and cornea.

History and etymology

The originally medieval Latin term comes from the Latin word uva ("grape") and is a reference to its grape-like appearance (reddish-blue or almost black colour, wrinkled appearance and grape-like size and shape when stripped intact from a cadaveric eye). In fact, it is a partial loan translation of the Ancient Greek term for the choroid, which literally means “covering resembling a grape”.[2][3] Its use as a technical term for part of the eye is ancient, but it only referred to the choroid in Middle English and before.[4][5]

Structure

Regions

The uvea is the vascular middle layer of the eye. It is traditionally divided into three areas, from front to back:

Function

The prime functions of the uveal tract as a unit are:

  • Nutrition and gas exchange: uveal vessels directly perfuse the ciliary body and iris, to support their metabolic needs, and indirectly supply diffusible nutrients to the outer retina, sclera, and lens, which lack any intrinsic blood supply. (The cornea has no adjacent blood vessels and is oxygenated by direct gas exchange with the environment.)
  • Light absorption: the uvea improves the contrast of the retinal image by reducing reflected light within the eye (analogous to the black paint inside a camera), and also absorbs outside light transmitted through the sclera, which is not fully opaque.

In addition, some uveal regions have special functions of great importance, including secretion of the aqueous humour by the ciliary processes, control of accommodation (focus) by the ciliary body, and optimisation of retinal illumination by the iris's control over the pupil. Many of these functions are under the control of the autonomic nervous system.

Pharmacology

The pupil provides a visible example of the neural feedback control in the body. This is subserved by a balance between the antagonistic sympathetic and parasympathetic divisions of the autonomic nervous system. Informal pharmacological experiments have been performed on the pupil for centuries, since the pupil is readily visible, and its size can be readily altered by applying drugs—even crude plant extracts—to the cornea. Pharmacological control over pupil size remains an important part of the treatment of some ocular diseases.

Drugs can also reduce the metabolically active process of secreting aqueous humour, which is important in treating both acute and chronic glaucoma.

Immunology

The normal uvea consists of immune competent cells, particularly lymphocytes, and is prone to respond to inflammation by developing lymphocytic infiltrates. A rare disease called sympathetic ophthalmia may represent 'cross-reaction' between the uveal and retinal antigens (i.e., the body's inability to distinguish between them, with resulting misdirected inflammatory reactions).

Clinical significance

See uveitis, choroiditis, iritis, iridocyclitis, anterior uveitis, sympathetic ophthalmia, and uveal melanoma.

References

  1. ^ Oxford English Dictionary: uvea
  2. ^ Lidell and Scott. A Greek-English Lexicon
  3. ^ Encyclopaedia Britannica: The uvea
  4. ^ Oxford English Dictionary: uvea
  5. ^ Lloyd, G. E. R. (21 October 2002). The Ambitions of Curiosity: Understanding the World in Ancient Greece and China. Cambridge University Press. ISBN 9780521894616.

Read other articles:

No Matter What (seri televisi)

No Matter WhatPoster promosiHangul누가 뭐래도 GenreDrama keluargaPercintaanKomediPembuatKBS Drama ProductionDitulis olehGo Bong-hwangSutradaraSung Joon-haePemeranNa Hye-miChoi WoongJung Min-ahJung HeonNegara asalKorea SelatanBahasa asliKoreaJmlh. episode120ProduksiProduser eksekutifJeon Woo-sungProduserSung Joon-haePengaturan kameraKamera tunggalDurasi30 menitRumah produksiKBS Drama ProductionDistributorKBSRilis asliJaringanKBS1Format gambar1080i (HDTV)Format audioDolby DigitalRilis12 O...

 

Pembunuhan ganda dan bunuh diri Chris Benoit

Chris BenoitLokasiFayetteville, Georgia, Amerika SerikatTanggal22–25 Juni 2007 (Zona Waktu Timur)Jenis seranganPembunuhan-bunuh diriKorban tewas3 (termasuk pelaku)PelakuChris Benoit Pembunuhan ganda dan bunuh diri Chris Benoit merupakan sebuah peristiwa tragis yang terjadi selama tiga hari berakhir pada tanggal 24 Juni 2007. Seorang pegulat profesional World Wrestling Entertainment (WWE) bernama Chris Benoit membunuh istrinya, Nancy Benoit serta mencekik anaknya yang berusia tujuh tahun, Da...

 

2016 Kirklees Metropolitan Borough Council election

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: 2016 Kirklees Metropolitan Borough Council election – news · newspapers · books · scholar · JSTOR (April 2016) (Learn how and when to remove this template message) 2016 local election results in Kirklees The 2016 Kirklees Metropolitan Borough Council election t...

Charity Shield FA 1933

Charity Shield FA 1933TurnamenCharity Shield FA Arsenal Everton 3 0 Tanggal18 Oktober 1933StadionGoodison Park, Liverpool← 1932 1934 → Charity Shield FA 1933 adalah pertandingan sepak bola antara Arsenal dan Everton yang diselenggarakan pada 18 Oktober 1933 di Goodison Park, Liverpool. Pertandingan ini merupakan pertandingan ke-20 dari penyelenggaraan Charity Shield FA. Pertandingan ini dimenangkan oleh Arsenal dengan skor 3–0.[1] Pertandingan Arsenal v Everton 18 Oktobe...

 

Sanhedrin

Ilustrasi Sanhedrin saat mengadili Yesus Orang Yahudi Agama Yahudi Agama Tuhan Allah dalam Yudaisme Dasar Iman Yahudi Kaballah Hari raya Doa Halakha Mitzvot (Daftar: 613) Rabi Sinagoge Pembacaan gulungan Taurat Minhag/Kebiasaan Tzedakah Teks Tanakh: Taurat Nevi'im Ketuvim Literatur Rabinik Talmud Mishnah Gemara Etnis Ashkenazi Sefardim Mizrahi Beta Israel Penduduk (Daftar) Israel AS Rusia/Uni Soviet SpanyolKanada Jerman Prancis Britania Raya Amerika Latin Polandia Dunia Arab Malaysia Yaman Ya...

 

Hiperpituitarisme

Gigantisme, salah satu akibat hiperpituitarisme Hiperpituitarisme adalah sebuah kondisi yang menghasilkan sekresi kelebihan hormon yang disekresikan dari kelenjar pituitari.[1] Hiperpituitarisme, atau hipersekresi utama hormon hipofisis, jarang terjadi pada anak-anak.[2] Hiperpituitarisme biasanya hasil dari mikroadenoma hipofisis.[2] Yang paling sering ditemui pada anak-anak adenoma adalah prolaktinoma, diikuti oleh kortikotropinoma dan somatotropinoma.[2] Kur...

Eastern Orthodoxy in Croatia

Aspect of religious life in Croatia Gomirje Monastery Eastern Orthodoxy in Croatia refers to adherents, religious communities, institutions and organizations of Eastern Orthodox Christianity in Croatia. It is the second-largest religious denomination in Croatia, behind the Roman Catholic Church. Over 128 000 people, forming 3.32% of the total Croatian population, are Eastern Orthodox Christians (2021). Eastern Orthodoxy in Croatia is represented foremost by the Serbian Orthodox Church, which ...

 

Parking lot

Cleared area for parking vehicles For other uses, see Parking lot (disambiguation). For parking areas along highways, see Rest area. Diagram of example parking lot layout with angle parking as seen from above A parking lot in Manhattan, New York City, in 2010, with its capacity increased through multiple level stacked parking using mechanical lifts A subterranean parking lot of a Brazilian shopping mall taken in 2016 A sign at the entrance to an underground parking garage in March 2007, warni...

 

Siwa culture

Not to be confused with Siba culture. Siwa cultureArea map of the Siwa culture, with main sites (): Ya’er, Lanqiao, Xujianian, Jiuzhan... Also shown: the Chinese capital of Xi'an () and the Western Zhou frontier outpost of Baicaopo ()Geographical rangeupper Yellow RiverPeriodBronze AgeDatesc. 1300 – c. 600 BCEPreceded byMajiayao cultureQijia cultureFollowed byOrdos cultureShajing cultureHan dynastyChinese nameSimplified Chinese寺洼文化TranscriptionsStandard MandarinHanyu PinyinSìwā ...

祖基菲里阿末

这是马来族人名，“阿末”是父名，不是姓氏，提及此人时应以其自身的名“祖基菲里”为主。 尊敬的拿督斯里哈芝祖基菲里·阿末Dzulkefly bin Ahmad国会议员、DGSM博士 马来西亚卫生部部长现任就任日期2023年12月12日君主最高元首苏丹阿都拉最高元首苏丹依布拉欣·依斯迈首相安华·依布拉欣副职卡尼斯曼（英语：Lukanisman Awang Sauni）前任扎丽哈·慕斯达法任期2018年5月21日—2...

 

Новотитаровское сельское поселение

Сельское поселение России (МО 2-го уровня)Новотитаровское сельское поселение Флаг[d] Герб 45°14′09″ с. ш. 38°58′16″ в. д.HGЯO Страна  Россия Субъект РФ Краснодарский край Район Динской Включает 4 населённых пункта Адм. центр Новотитаровская Глава сельского пос�...

 

2020年夏季奧林匹克運動會波蘭代表團

2020年夏季奥林匹克运动会波兰代表團波兰国旗IOC編碼POLNOC波蘭奧林匹克委員會網站olimpijski.pl（英文）（波兰文）2020年夏季奥林匹克运动会（東京）2021年7月23日至8月8日（受2019冠状病毒病疫情影响推迟，但仍保留原定名称）運動員206參賽項目24个大项旗手开幕式：帕维尔·科热尼奥夫斯基（游泳）和马娅·沃什乔夫斯卡（自行车）[1]闭幕式：卡罗利娜·纳亚（皮划艇）&#...

Emma Calvé

French operatic soprano (1858-1942) This article includes a list of general references, but it lacks sufficient corresponding inline citations. Please help to improve this article by introducing more precise citations. (February 2013) (Learn how and when to remove this message) Emma CalvéEmma Calvé as CarmenBornRosa Emma Calvet(1858-08-15)15 August 1858Decazeville, AveyronDied6 January 1942(1942-01-06) (aged 83)Montpellier, HéraultNationalityFrenchOccupationOperatic dramatic sopranoSp...

 

Government of the Philippines

National government of the Philippines Government of the PhilippinesPamahalaan ng PilipinasCoat of arms of the PhilippinesJurisdictionRepublic of the PhilippinesWebsitewww.gov.phLegislative branchLegislatureCongressMeeting placeBatasang Pambansa Complex(House of Representatives)GSIS Building (Senate) Executive branchLeaderPresidentAppointerDirect popular voteHeadquartersMalacañang PalaceMain organCabinetDepartmentsExecutive departments of the PhilippinesJudicial branchCourtSupreme CourtSeatM...

 

Magnates of Poland and Lithuania

Painting, by Jan Matejko, of Polish magnates (1697–1795). For their names, please see image description [1]. A Polish lord's journey during reign of King August III, by Jan Chełmiński, 1880 Possessions of Polish magnates in 16th–17th centuries The magnates of Poland and Lithuania (Polish: magnateria) were an aristocracy of Polish-Lithuanian nobility (szlachta) that existed in the Crown of the Kingdom of Poland, in the Grand Duchy of Lithuania and, from the 1569 Union of Lublin, in the P...

Romanian cuisine

Culinary traditions of Romania Not to be confused with Romani cuisine or Roman cuisine. This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: Romanian cuisine – news · newspapers · books · scholar · JSTOR (November 2023) (Learn how and when to remove this message) Part of a series on theCulture of Romania History ...

 

Funk carioca

Funk carioca Données clés Origines stylistiques Miami bass, freestyle Origines culturelles Milieu des années 1980 ; Rio de Janeiro, Brésil Instruments typiques Boîte à rythmes, synthétiseur, échantillonneur, voix Genres dérivés Proibidão, funk melody, funk ostentação, funk ousadia, brega funk, electrofunk modifier Le funk carioca, aussi appelé funk brasileiro ou funky, — funk de favela ou baile funk dans le monde anglophone — est un genre de musique électron...

 

Conchita Martínez

Spanish tennis player (born 1972) For another tennis player born 1976, see Conchita Martínez Granados. In this Spanish name, the first or paternal surname is Martínez and the second or maternal family name is Bernat . Conchita MartínezConchita Martínez at the 2010 US OpenFull nameInmaculada Concepción Martínez BernatCountry (sports) SpainResidenceBarcelona, SpainBorn (1972-04-16) 16 April 1972 (age 52)Monzón, Huesca, SpainHeight1.73 m (5 ft 8 ...

Emoji - Accendi le emozioni

Emoji - Accendi le emozioniGhimmifive e Gene in una scena del filmTitolo originaleThe Emoji Movie Lingua originaleinglese Paese di produzioneStati Uniti d'America Anno2017 Durata86 min Rapporto2,35:1 Genereanimazione, commedia, avventura RegiaTony Leondis SceneggiaturaEric Siegel, Tony Leondis, Mike White, Jordan Roberts ProduttoreDavid Lazer, Michelle Raimo Casa di produzioneSony Pictures Animation, Columbia Pictures Distribuzione in italianoWarner Bros., Sony Pictures MontaggioWilli...

 

Joseph Bernelle

French Army officer Portrait of French General Joseph Bernelle Joseph Bernelle (5 October 1785 Versailles, France Versailles, France 7 January 1871 Paris, France) was a French Army officer who commanded the French Foreign Legion during the Carlist War. Early years and Grande Armée service He was born in 1785 to General Pierre-Antoine and his wife, Lady Marguerite Desnoyers.[citation needed] He entered the École spéciale militaire de Saint-Cyr in 1801 and was commissioned as sous-li...