View source for Lisch nodule

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| name            =  Lisch nodule
| synonyms        = Iris hamartoma
| image           = Lisch nodules.JPG
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| caption         = Lisch nodules on surface of iris
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'''Lisch nodule''', also known as '''iris hamartoma''', is a pigmented [[hamartoma]]tous nodular aggregate of dendritic [[melanocyte]]s affecting the [[Iris (anatomy)|iris]],<ref name=robbins7>{{Citation |author1=Kumar, Vinay |author2=Fausto, Nelson |author3=Fausto, Nelso |author4=Robbins, Stanley L. |author5=Abbas, Abul K. |author6=Cotran, Ramzi S. | title=Robbins and Cotran Pathologic Basis of Disease | year=2005 | edition=7th| publisher=Elsevier Saunders | location=Philadelphia | isbn=0-7216-0187-1 | page=169}}</ref> named after Austrian [[ophthalmology|ophthalmologist]] [[Karl Lisch]] (1907–1999), who first recognized them in 1937.<ref name=Lukacs1997>{{citation |author1=Lukacs, Andreas |author2=Junk, Anna K. |author3=Fritz, Stefani H. |author4=Kampik, Anselm |author5=Georg, Schirren Carl |author6=Plewig, Gerd | year = 1997 | title = Lisch nodules. Markers of neurofibromatosis 1 and immunohistochemical references for neuroectodermal differentiation | journal = Hautarzt | volume = 48 | issue = 1 | pages = 38–41 | doi = 10.1007/s001050050544 | pmid = 9132386|s2cid=26116325 }}</ref>

The first published use of the term ''Lisch nodule'' was in the ''[[The New England Journal of Medicine|New England Journal of Medicine]]'' "Medical Progress" series article of December 31, 1981 (Riccardi VM: Von Recklinghausen Neurofibromatosis. ''N Engl J Med'' 1981;305:1617–27).

These [[Nodule (medicine)|nodule]]s are found in [[neurofibromatosis type 1]], and are present in greater than 94% of patients over the age of six.<ref name=robbins7 /> They are clear, yellow-brown,<ref name=Richetta2004>{{citation |author1=Richetta, A. |author2=Giustini, A. |author3=Recupero, S. M. |author4=Pezza, M. |author5=Carlomagno, C. |author6=Amoruso, G. |author7=Calvieri, S. | year = 2004 | title = Lisch nodules of the iris in neurofibromatosis type 1 | journal = Journal of the European Academy of Dermatology and Venereology | volume = 18 | issue = 3 | pages = 342–4 | doi = 10.1111/j.1468-3083.2004.00915.x | url = http://www3.interscience.wiley.com/cgi-bin/fulltext/118788235/PDFSTART | pmid = 15096151|s2cid=25745030 | url-access = subscription }}</ref> oval to round, dome-shaped [[papules]] that project from the surface of the iris.  These nodules typically do not affect vision, but are very useful in diagnosis.<ref name=robbins7 /> They are detected by [[slit lamp]] examination.<ref name=Richetta2004 /> [[Immunohistochemistry]] stains positive against the proteins [[vimentin]] and [[S-100 protein|S-100]], and points to an [[ectoderm]]al origin for the nodules.<ref name=Lukacs1997/> Their precise origin and structure, however, are still under investigation.<ref name=Richetta2004 /> They can rarely be seen in [[neurofibromatosis type 2]].<ref>{{Cite journal|url=https://jamanetwork.com/journals/jamaophthalmology/article-abstract/638110|doi = 10.1001/archopht.1989.01070020649012|title = Lisch Nodules in Neurofibromatosis Type 2|year = 1989|last1 = Charles|first1 = S. J.|last2 = Moore|first2 = A. T.|last3 = Yates|first3 = J. R.|last4 = Ferguson-Smith|first4 = M. A.|journal = Archives of Ophthalmology|volume = 107|issue = 11|pages = 1571–1572|pmid = 2510706|url-access = subscription}}</ref>

== See also ==
* [[Glaucoma]]
* [[Watson syndrome]]

== References ==
{{reflist}}

{{Eponymous medical signs for eyes and ears}}

[[Category:Disturbances of human pigmentation]]
[[Category:Ophthalmology]]
[[Category:Eye color]]

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