Pannus is a medical term for an abnormal layer of fibrovascular tissue or granulation tissue. Common sites for pannus formation include over the cornea, over a joint surface (as seen in rheumatoid arthritis), or on a prosthetic heart valve. Pannus may grow in a tumor-like fashion, as in joints where it may erode articular cartilage and bone.

The term pannus is often used incorrectly to refer to a panniculus (a hanging flap of tissue), though pannus can also refer to panniculus adiposus.

Pannus in rheumatoid arthritis

In people suffering from rheumatoid arthritis, pannus tissue eventually forms in the joint affected by the disease, causing loss of bone and cartilage. From Autoimmunity and Disease by Harley Y. Tse and Michail K. Shaw:

Chronic stages of the disease typically coincide with the formation of a structure known as a pannus. A pannus is a membrane of granulation tissue composed of mesenchyme- and bone marrow-derived cells. Formation of the pannus stimulates the release of IL-1, platelet-derived growth factor, prostaglandins, and substance P by macrophages, which ultimately cause cartilage destruction and bone erosion.

Pannus in ophthalmology

In ophthalmology, pannus refers to the growth of blood vessels into the peripheral cornea. In normal individuals, the cornea is avascular. Chronic local hypoxia (such as that occurring with overuse of contact lenses) or inflammation may lead to peripheral corneal vascularization, or pannus. Pannus may also develop in diseases of the corneal stem cells, such as aniridia. It is often solved by peritomy.

Wikimedia Foundation. 2010.

Look at other dictionaries:

  • pannus — ● pannus nom masculin (latin pannus, étoffe) Nodule inflammatoire du tissu conjonctif. ⇒PANNUS, subst. masc. MÉD., PATHOL. A. ,,Formation pathologique constituée de tissu inflammatoire et provenant de la synoviale des articulations (Méd. Biol.… …   Encyclopédie Universelle

  • pannus — m. reumat. Tejido inflamatorio de granulación, de origen sinovial, que recubre el cartílago articular en algunas artritis. l oftalm. Tejido en forma de velo de naturaleza conjuntiva, muy vascularizado y de neoformación que cubre parte o toda la… …   Diccionario médico

  • PANNUS — in Circensibus olim ludis, certô colore insignis, factiones discernebat; unde consuetudinem in Principum Aulis Nobilibusque familiis servitia variorum colorum pannis excolendi et ab aliis discernendi, quos Liureas hodie dicunt, ortam esse, haud… …   Hofmann J. Lexicon universale

  • Pannus — Pan nus, n. [L., cloth. See 2d {Pane}.] (Med.) A very vascular superficial opacity of the cornea, usually caused by granulation of the eyelids. Foster. [1913 Webster] …   The Collaborative International Dictionary of English

  • Pannus — (lat.), 1) so v.w. Honigfleck; 2) auch Augenfell …   Pierer's Universal-Lexikon

  • Pannus — Pannus, s. Hornhautentzündung …   Meyers Großes Konversations-Lexikon

  • Pannus — (lat., »Lappen«), Augenfell, Scharlachfell, eine entzündliche Auflagerung auf der Hornhaut …   Kleines Konversations-Lexikon

  • pannus — PÁNNUS s.n. v. panus. Trimis de LauraGellner, 13.09.2007. Sursa: DN …   Dicționar Român

  • pannus — (izg. pȁnus) m DEFINICIJA meteor. rastrgani dijelovi oblaka u obliku krpa, ispod podnice nimbostratusa i kumulonimbusa, katkada u sloju ETIMOLOGIJA lat.: krpa …   Hrvatski jezični portal

  • Pannus — Wolken: Klassifikation Gattungen Cirrus Ci Cirrocumulus Cc Cirrostratus Cs Altocumulus Ac Altostratus As Stratocumulus Sc Stratus St Cumulus Cu Nimbostratus Ns …   Deutsch Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.