Schlemm 's canal - wikipedia Schlemm 's canal Schlemm 's canal Anterior part of the human eye, with Canal of Schlemm at lower right. The upper half of a sagittal section through the front of the eyeball. ( Canal of Schlemm labeled at center left. ) Details Identifiers Latin sinus venosus sclerae TA A12. 3.06. 109 FMA 51873 Anatomical terminology ( edit on Wikidata ) Schlemm 's canal is a circular lymphatic - like vessel in the eye that collects aqueous humor from the anterior chamber and delivers it into the episcleral blood vessels via aqueous veins. It is named after Friedrich Schlemm ( 1795 -- 1858 ), a German anatomist. The canal is essentially an endothelium - lined tube, resembling that of a lymphatic vessel. On the inside of the canal, nearest to the aqueous humor, it is covered by the trabecular meshwork ; this region makes the greatest contribution to outflow resistance of the aqueous humor. Conventionally, the canal has been considered a blood vessel, but recent studies have revealed that the molecular identity of Schlemm 's canal is strikingly reminiscent to the one of lymphatic vasculature. Contents 1 Lymphatic - like identity 2 Canaloplasty 3 Additional images 4 See also 5 References 6 External links Lymphatic - like identity While conventional wisdom has considered Schlemm 's canal ( also known as the scleral venous sinus ) as vein, the canal shares several structural and functional features reminiscent of the lymphatic vasculature. Notably, it is never filled with blood in physiological settings as it does not receive arterial blood circulation. Three recent independent pioneering studies by Aleksanteri Aspelund and Kari Alitalo from the University of Helsinki, Dae - Young Park and Gou Young Koh from Institute for Basic Science and KAIST and Krishnakumar Kizhatil and Simon W.M. John from the Howard Hughes Medical Institute, discovered that Schlemm 's canal displays several features of lymphatic endothelium, including the expression of PROX1, VEGFR3, CCL21, FOXC2, but lacked the expression of LYVE1 and PDPN, indicating that Schlemm 's canal is a lymphatic - like vessel. Developmental studies revealed that Schlemm 's canal develops via a unique mechanism involving the transdifferentiation of venous endothelial cells in the eye into lymphatic - like endothelial cells. The developmental morphogenesis of the canal was sensitive to the inhibition of lymphangiogenic growth factors, and in adults, the administration of the lymphangiogenic growth factor VEGFC enlarged the Schlemm 's canal, which was associated with a reduction in intraocular pressure. In the combined absence of angiopoietin 1 and angiopoietin 2, Schlemm 's canal and episcleral lymphatic vasculature completely failed to develop, resulting in buphthalmos and glaucoma. Canaloplasty Canaloplasty is a procedure designed to enhance and restore the eye 's natural drainage system to provide sustained reduction of intraocular pressure. Canaloplasty utilizes micro catheters in a simple and minimally invasive procedure. To perform a canaloplasty, a surgeon will create a tiny incision to gain access to Schlemm 's canal. A microcatheter circumnavigates Schlemm 's canal around the iris, enlarging the main drainage channel and its smaller collector channels through the injection of a sterile, gel - like material called viscoelastic. The catheter is then removed and a suture is placed within the canal and tightened. By opening Schlemm 's canal, the pressure inside the eye is relieved. Long - term results are available, published in May 2009 in the Journal of Cataract and Refractive Surgery. Additional images Enlarged general view of the iridial angle. ( Labeled with older label of ' sinus venosus scleræ ' at center top. ) See also Intraocular pressure Ocular hypertension References Jump up ^ Cassin, B. and Solomon, S. Dictionary of Eye Terminology. Gainesville, Florida : Triad Publishing Company, 1990. ^ Jump up to : Aleksanteri Aspelund, Tuomas Tammela, Salli Antila, Harri Nurmi, Veli - Matti Leppänen, Georgia Zarkada, Lukas Stanczuk, Mathias Francois, Taija Mäkinen, Pipsa Saharinen, Ilkka Immonen, and Kari Alitalo. ( 2014 ). `` The Schlemm 's canal is a VEGF - C / VEGFR - 3 - responsive lymphatic - like vessel ''. The Journal of Clinical Investigation. 124 : 3975 -- 86. doi : 10.1172 / JCI75395. PMC 4153703. PMID 25061878. CS1 maint : Uses authors parameter ( link ) ^ Jump up to : Dae - Young Park, Junyeop Lee, Intae Park, Dongwon Choi, Sunju Lee, Sukhyun Song, Yoonha Hwang, Ki Yong Hong, Yoshikazu Nakaoka, Taija Makinen, Pilhan Kim, Kari Alitalo, Young - Kwon Hong, and Gou Young Koh ( 2014 ). `` Lymphatic regulator PROX1 determines Schlemm 's canal integrity and identity ''. The Journal of Clinical Investigation. 124 : 3960 -- 74. doi : 10.1172 / JCI75392. PMC 4153702. PMID 25061877. CS1 maint : Uses authors parameter ( link ) ^ Jump up to : Krishnakumar Kizhatil, Margaret Ryan, Jeffrey K. Marchant, Stephen Henrich, Simon W.M. John ( 2014 ). `` Schlemm 's canal is a unique vessel with a combination of blood vascular and lymphatic phenotypes that forms by a novel developmental process ''. PLoS Biology. 12 : e1001912. doi : 10.1371 / journal. pbio. 1001912. PMC 4106723. PMID 25051267. CS1 maint : Uses authors parameter ( link ) Jump up ^ Ramos RF, Hoying JB, Witte MH, Daniel Stamer W. ( 2007 ). `` Schlemm 's canal endothelia, lymphatic, or blood vasculature ? ''. J Glaucoma. 16 : 391 -- 405. doi : 10.1097 / IJG. 0b013e3180654ac6. PMID 17571003. CS1 maint : Uses authors parameter ( link ) Jump up ^ Thomson BR, Heinen S, Jeansson M, Ghosh AK, Fatima A, Sung HK, Onay T, Chen H, Yamaguchi S, Economides AN, Flenniken A, Gale NW, Hong YK, Fawzi A, Liu X, Kume T, Quaggin SE. ( 2014 ). `` A lymphatic defect causes ocular hypertension and glaucoma in mice ''. The Journal of Clinical Investigation. 124 : 4320 -- 24. doi : 10.1172 / JCI77162. PMC 4191022. PMID 25202984. CS1 maint : Uses authors parameter ( link ) Jump up ^ https://mediamillinc.com/vjo.php?display=video&id=013 Jump up ^ http://www.jcrsjournal.org/article/S0886-3350(08)00004-7/abstract, Jump up ^ http://www.jcrsjournal.org/article/S0886-3350(07)00697-9/abstract Jump up ^ http://www.jcrsjournal.org/article/S0886-3350(09)00139-4/abstract External links Histology image : 08005loa -- Histology Learning System at Boston University Diagram Diagram Anatomy of the globe of the eye Fibrous tunic ( outer ) Sclera Episcleral layer Schlemm 's canal Trabecular meshwork Cornea Limbus layers Epithelium Bowman 's Stroma Dua 's layer Descemet 's Endothelium Uvea / vascular tunic ( middle ) Choroid Capillary lamina of choroid Bruch 's membrane Sattler 's layer Ciliary body Ciliary processes Ciliary muscle Pars plicata Pars plana Iris Stroma Pupil Iris dilator muscle Iris sphincter muscle Retina ( inner ) Layers Inner limiting membrane Nerve fiber layer Ganglion cell layer Inner plexiform layer Inner nuclear layer Outer plexiform layer Outer nuclear layer External limiting membrane Layer of rods and cones Retinal pigment epithelium Cells Photoreceptor cells ( Cone cell, Rod cell ) → ( Horizontal cell ) → Bipolar cell → ( Amacrine cell ) → Retina ganglion cell ( Midget cell, Parasol cell, Bistratified cell, Giant retina ganglion cells, Photosensitive ganglion cell ) → Diencephalon : P cell, M cell, K cell, Muller glia Other Macula Perifoveal area Parafoveal area Fovea Foveal avascular zone Foveola Optic disc Optic cup Ora serrata Anatomical regions of the eye Anterior segment Adnexa Fibrous tunic Anterior chamber Aqueous humour Iris Posterior chamber Ciliary body Lens Capsule of lens Zonule of Zinn Posterior segment Vitreous chamber Vitreous body Retina Choroid Other Keratocytes Ocular immune system Tapetum lucidum Eye care professional Eye disease Refractive error Accommodation Physiological Optics Visual perception Retrieved from `` https://en.wikipedia.org/w/index.php?title=Schlemm%27s_canal&oldid=810100179 '' Categories : Human eye anatomy Hidden categories : CS1 maint : Uses authors parameter Medicine infobox template using GraySubject or GrayPage Talk Contents About Wikipedia Bosanski Català Deutsch Eesti Español Français Italiano Nederlands Polski Português Русский Suomi Татарча / tatarça Українська Edit links This page was last edited on 13 November 2017, at 09 : 47. Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: where is the canal of schlemm what is its medical significance
Answer: a circular lymphatic-like vessel in the eye that collects aqueous humor from the anterior chamber and delivers it into the episcleral blood vessels