{{Short description|Type of eye surgery}} {{Infobox medical intervention | Name = Glaucoma surgery | Image = Conventional_surgery_to_treat_glaucoma_EDA11.JPG | Caption = Trabeculectomy for treating glaucoma | ICD10 = | ICD9 = {{ICD9proc|12.1}}-{{ICD9proc|12.7}} | MeshID = | OPS301 = | OtherCodes = | HCPCSlevel2 = }}
'''Glaucoma surgery''' is a type of eye surgery performed to treat glaucoma, a group of diseases which affect the optic nerve, resulting in vision loss. Glaucoma is characterized by increased intraocular pressure (IOP). Most glaucoma surgeries seek to lower IOP by facilitating the escape of excess aqueous humor from the eye, while others decrease the production of aqueous humor.
==Procedures that facilitate outflow of aqueous humor== ===Filtering procedures=== Filtering surgeries are the mainstay of surgical treatment to control intraocular pressure.<ref name="Jacobi97">{{cite journal |vauthors=Jacobi PC, Dietlein TS, Krieglstein GK |date=April 1997 |title=Technique of goniocurettage: a potential treatment for advanced chronic open angle glaucoma |journal=Br J Ophthalmol |volume=81 |issue=4 |pages=302–7 |doi=10.1136/bjo.81.4.302 |pmc=1722166 |pmid=9215060}}</ref> An '''anterior sclerotomy''' or '''sclerostomy''' is used to gain access to the inner layers of the eye<ref>{{cite web |title=Search |url=http://www.merckmedicus.com/pp/us/hcp/thcp_dorlands_content.jsp?pg=/ppdocs/us/common/dorlands/dorland/dmd_s_05.htm |archive-url=https://web.archive.org/web/20060614054631/http://www.merckmedicus.com/pp/us/hcp/thcp_dorlands_content.jsp?pg=%2Fppdocs%2Fus%2Fcommon%2Fdorlands%2Fdorland%2Fdmd_s_05.htm |archive-date=2006-06-14 |access-date=2006-10-11}}</ref><ref>{{cite journal |vauthors=Berlin MS, Yoo PH, Ahn RJ |date=April 1995 |title=The role of laser sclerostomy in glaucoma surgery |journal=Curr Opin Ophthalmol |volume=6 |issue=2 |pages=102–14 |doi=10.1097/00055735-199504000-00016 |pmid=10150851 |s2cid=12008149}}</ref> in order to create a drainage channel from the anterior chamber to the external surface of the eye under the conjunctiva, allowing aqueous to seep into a bleb from which it is slowly absorbed. Filtering procedures are typically divided into either penetrating or non-penetrating types depending upon whether an intraoperative entry into the anterior chamber occurs.<ref>{{cite web |title=Aging: Glaucoma: The Perils of High Pressure - the Doctor |url=http://www.thedoctorwillseeyounow.com/content/aging/art2105.html/ |archive-url=https://web.archive.org/web/20140727194508/http://www.thedoctorwillseeyounow.com/content/aging/art2105.html |archive-date=2014-07-27 |access-date=2014-06-11}}</ref><ref name="jdosmp.org">{{cite web |title=Filtering Surgeries for Glaucoma - Dr Nutan S - Jabalpur Divisional Ophthalmic Society |url=http://www.jdosmp.org/lectures/ns_filtering_surgeries.htm |archive-url=https://web.archive.org/web/20110821021821/http://jdosmp.org/lectures/ns_filtering_surgeries.htm |archive-date=2011-08-21 |access-date=2014-06-11}}</ref>
====Penetrating filtering surgeries==== Penetrating filtering surgeries are further subdivided into guarded filtering procedures, also known as protected, subscleral, or partial thickness filtering procedures (in which the surgeon sutures a scleral flap over the sclerostomy site<ref name="revoptom.com">{{cite web |title=Hypotony Maculopathy Secondary to Overfiltering Bleb |url=http://www.revoptom.com/content/d/news_review/c/18587/dnnprintmode/true/?skinsrc=%5Bl%5Dskins/ro2009 |archive-url=https://web.archive.org/web/20140714155027/http://www.revoptom.com/content/d/news_review/c/18587/dnnprintmode/true/?skinsrc=%5Bl%5Dskins/ro2009 |archive-date=2014-07-14 |access-date=2023-08-19}}</ref>), and full thickness procedures.<ref>{{cite web |date=2007-11-12 |title=Glaucoma |url=http://adam.about.com/reports/000025_8.htm |archive-url=https://web.archive.org/web/20090403021521/http://adam.about.com/reports/000025_8.htm |archive-date=2009-04-03 |access-date=2012-12-11 |publisher=Adam.about.com}}</ref>
Trabeculectomy is a guarded filtering procedure that removes of part of the trabecular meshwork.<ref>[http://www.surgeryencyclopedia.com/St-Wr/Trabeculectomy.html Surgery Encyclopedia - Trabeculectomy]</ref><ref>{{cite web |title=Eye Procedures > Glaucoma Filtration Procedure (Trabeculectomy) - EyeMDLink.com |url=http://www.eyemdlink.com/EyeProcedure.asp?EyeProcedureID=44 |archive-url=https://web.archive.org/web/20061111074228/http://www.eyemdlink.com/EyeProcedure.asp?EyeProcedureID=44 |archive-date=2006-11-11 |access-date=2022-04-19}}</ref> Full thickness procedures include sclerectomy, posterior lip sclerectomy (in which the surgeon completely excises the sclera on the area of the sclerostomy<ref name="revoptom.com"/>), trephination, thermal sclerostomy (Scheie procedure), iridenclesis, and sclerostomy (including conventional sclerostomy and enzymatic sclerostomy).<ref name="jdosmp.org"/><ref>{{cite web |title=Sclerostomy - procedure, recovery, test, blood, pain, complications, adults, time, infection, medication, types, risk, rate, Definition, Purpose, Demographics, Description |url=http://www.surgeryencyclopedia.com/Pa-St/Sclerostomy.html |access-date=2012-12-11 |publisher=Surgeryencyclopedia.com}}</ref>
Anterior chamber paracentesis is a penetrating surgical procedure done to reduce intraocular pressure of the eye.<ref name="JML">{{cite journal |last1=Cioboata |first1=M |last2=Anghelie |first2=A |last3=Chiotan |first3=C |last4=Liora |first4=R |last5=Serban |first5=R |last6=Cornăcel |first6=C |date=2014 |title=Benefits of anterior chamber paracentesis in the management of glaucomatous emergencies |journal=Journal of Medicine and Life |volume=7 |issue=Spec Iss 2 |pages=5–6 |issn=1844-122X |pmc=4391354 |pmid=25870663}}</ref>
====Non-penetrating filtering surgeries==== Non-penetrating filtering surgeries do not penetrate or enter the eye's anterior chamber.<ref>{{cite journal |vauthors=Hamard P, Lachkar Y |date=May 2002 |title=[Non penetrating filtering surgery, evolution and results] |url=http://www.masson.fr/masson/MDOI-JFO-05-2002-25-5-0181-5512-101019-ART12 |journal=J Fr Ophtalmol |language=fr |volume=25 |issue=5 |pages=527–36 |pmid=12048520 }}{{Dead link|date=January 2026 |bot=InternetArchiveBot }}</ref><ref>{{cite journal |vauthors=Lachkar Y, Hamard P |date=April 2002 |title=Nonpenetrating filtering surgery |journal=Curr Opin Ophthalmol |volume=13 |issue=2 |pages=110–5 |doi=10.1097/00055735-200204000-00010 |pmid=11880725 |s2cid=24144634}}</ref> There are two types of non-penetrating surgeries: Bleb-forming and viscocanalostomy.<ref>{{cite web |title=CE Lesson |url=http://cms.revoptom.com/print.asp?page=osc%2Ffeb03%2Flesson.htm |archive-url=https://web.archive.org/web/20140714182210/http://cms.revoptom.com/print.asp?page=osc%2Ffeb03%2Flesson.htm |archive-date=2014-07-14 |access-date=2019-11-24}}</ref><ref name="Gupta">{{cite web |title=Archived copy |url=http://www.optometry.co.uk/uploads/articles/331aa73495c19582cb2afe54c0a85671_Gupta19805.pdf |archive-url=https://web.archive.org/web/20140714111157/http://www.optometry.co.uk/uploads/articles/331aa73495c19582cb2afe54c0a85671_Gupta19805.pdf |archive-date=2014-07-14 |access-date=2014-06-11}}</ref> Bleb forming procedures include ab externo trabeculectomy and deep sclerectomy.<ref name=Gupta/>
Ab externo trabeculectomy (AET) involves cutting from outside the eye inward to reach Schlemm's canal, the trabecular meshwork, and the anterior chamber. Also known as non-penetrating trabeculectomy (NPT), it is an ab externo (from the outside), major ocular procedure in which Schlemm's canal is surgically exposed by making a large and very deep scleral flap. The inner wall of Schlemm's canal is stripped off after surgically exposing the canal. Deep sclerectomy, also known as nonpenetrating deep sclerectomy (PDS) or nonpenetrating trabeculectomy, is a filtering surgery where the internal wall of Schlemm's canal is excised, allowing subconjunctival filtration without actually entering the anterior chamber.<ref>{{cite journal |vauthors=Lachkar Y, Neverauskiene J, Jeanteur-Lunel MN, et al. |year=2004 |title=Nonpenetrating deep sclerectomy: a 6-year retrospective study |journal=Eur J Ophthalmol |volume=14 |issue=1 |pages=26–36 |doi=10.1177/112067210401400105 |pmid=15005582 |s2cid=36569523}}</ref>
In order to prevent wound adhesion after deep scleral excision and maintain good filtering results, it is sometimes performed with a variety of biocompatible spacers or devices, such as the Aquaflow collagen wick,<ref>{{cite web |title=Making the Case for Nonpenetrating Surgery |url=http://www.revophth.com/content/d/glaucoma_management/i/1312/c/25259/ |archive-url=https://web.archive.org/web/20140714185704/http://www.revophth.com/content/d/glaucoma_management/i/1312/c/25259/ |archive-date=2014-07-14 |access-date=2023-08-19}}</ref> ologen Collagen Matrix,<ref>{{cite journal |last=Aptel |first=F |author2=Dumas S |author3=Denis P |year=2009 |title=Ultrasound biomicroscopy and optical coherence tomography imaging of filtering blebs after deep sclerectomy with new collagen implant |journal=Eur J Ophthalmol |volume=19 |issue=2 |pages=223–30 |doi=10.1177/112067210901900208 |pmid=19253238 |s2cid=22594085}}</ref><ref>{{cite journal |last=Tanuj |first=D |author2=Amit S |author3=Saptorshi M |author4=Meenakshi G |date=May 2013 |title=Combined Subconjunctival and Subscleral Ologen Implant Insertion In Trabeculectomy |journal=Eye |volume=27 |issue=7 |page=889 |doi=10.1038/eye.2013.76 |pmc=3709396 |pmid=23640614}}</ref><ref>{{cite web |last=Matthew |first=SJ |author2=Sarkisian S |author3=Nathan B |author4=James MR |title=Initial experience using a collagen matrix implant (ologen) as a wound modulator with canaloplasty: 12 month results |url=http://www.abstractsonline.com/Plan/ViewAbstract.aspx?mID=2866&sKey=aa4eef9a-b55d-43a5-a9f7-c71c79616c08&cKey=7035e4dc-493a-4f51-adae-eedc3adbe114&mKey=%7BF0FCE029-9BF8-4E7C-B48E-9FF7711D4A0E%7D |access-date=12 December 2020 |publisher=2012 ARVO Congress, Ft. Lauderdale}}</ref> or Xenoplast glaucoma implant.<ref>{{cite web |title=Biological drainage – Xenoplast in glaucoma surgery (experimental and 10-year of clinical follow-up) |url=http://www.oic.it/~egscopenaghen2012/posters/june18/P2.24/poster.pdf |archive-url=https://web.archive.org/web/20131017051726/http://www.oic.it/~egscopenaghen2012/posters/june18/P2.24/poster.pdf |archive-date=17 October 2013 |access-date=12 December 2020 |publisher=2012 EGS Congress, Copenhagen |vauthors=Anisimova SY, Anisimova SI, Larionov EV}}</ref>
'''Viscocanalostomy''' is also an ab externo, major ocular procedure in which Schlemm's canal is surgically exposed by making a large and very deep scleral flap. In the VC procedure, Schlemm's canal is cannulated and viscoelastic substance injected (which dilates Schlemm's canal and the aqueous collector channels).{{cn|date=December 2025}}
Where wound modulation is needed to prevent closure of surgically created drainage channels, adjuvants such as the ologen collagen matrix implants may be used to facilitate healthy tissue regeneration. Scar formation at the site of excision or operation may block aqueous humor circulation, while healthy tissue regeneration will keep newly created drainage channels functional.<ref>{{cite journal |author=Dada T, Sharma R, Sinha G, Angmo D, Temkar S |year=2016 |title=Cyclodialysis-enhanced trabeculectomy with triple Ologen implantation |journal=Eur J Ophthalmol |volume=26 |issue=1 |pages=95–7 |doi=10.5301/ejo.5000633 |pmid=26044372 |s2cid=83593}}</ref><ref>{{cite journal |author=Min JK, Kee CW, Sohn SW, Lee HJ, Woo JM, Yim JH |year=2013 |title=Surgical outcome of mitomycin C-soaked collagen matrix implant in trabeculectomy |journal=J Glaucoma |volume=22 |issue=6 |pages=456–62 |doi=10.1097/IJG.0b013e31826ab6b1 |pmid=23263152 |s2cid=20615016}}</ref><ref>{{cite journal |author=Tanuj D, Amit S, Saptorshi M, Meenakshi G |year=2013 |title=Combined subconjunctival and subscleral ologen implant insertion in trabeculectomy |journal=Eye (Lond) |volume=27 |issue=7 |page=889 |doi=10.1038/eye.2013.76 |pmc=3709396 |pmid=23640614}}</ref><ref>{{cite journal |author=Aptel F, Dumas S, Denis P |year=2009 |title=Ultrasound biomicroscopy and optical coherence tomography imaging of filtering blebs after deep sclerectomy with new collagen implant |journal=Eur J Ophthalmol |volume=19 |issue=2 |pages=223–30 |doi=10.1177/112067210901900208 |pmid=19253238 |s2cid=22594085}}</ref>
===Laser trabeculoplasty=== {{Main article|Trabeculoplasty}} A trabeculoplasty is a modification of the trabecular meshwork. Laser trabeculoplasty (LTP) is the application of a laser beam to burn areas of the trabecular meshwork, located near the base of the iris, to increase fluid outflow. LTP is used in the treatment of various open-angle glaucomas.<ref>{{cite web |title=University of Michigan Health System - Surgery for Glaucoma |url=http://www.med.umich.edu/1libr/aha/aha_gfollow_oph.htm |archive-url=https://web.archive.org/web/20060904070642/http://www.med.umich.edu/1libr/aha/aha_gfollow_oph.htm |archive-date=2006-09-04 |access-date=2006-10-11}}</ref>
The two types of laser trabeculoplasty are '''argon laser trabeculoplasty''' (ALT) and '''selective laser trabeculoplasty''' (SLT). As its name suggests, argon laser trabeculoplasty uses an argon laser to create tiny burns on the trabecular meshwork.<ref>{{cite web |title=EyeMDLink.com - Argon Laser Trabeculoplasty (ALT) |url=http://www.eyemdlink.com/EyeProcedure.asp?EyeProcedureID=47 |archive-url=https://web.archive.org/web/20061111074253/http://www.eyemdlink.com/EyeProcedure.asp?EyeProcedureID=47 |archive-date=2006-11-11 |access-date=2006-10-11}}</ref> Selective laser trabeculoplasty is newer technology that uses a Nd:YAG laser to target specific cells within the trabecular meshwork and create less thermal damage than ALT.<ref>{{cite web |title=Review of Optometry - SLT: The Laser Picks Up Where Medications Leave Off |url=http://www.revoptom.com/index.asp?ArticleType=SiteSpec&page=osc%2F105058%2Flesson.htm |archive-url=https://web.archive.org/web/20061017043924/http://www.revoptom.com/index.asp?ArticleType=SiteSpec&page=osc%2F105058%2Flesson.htm |archive-date=2006-10-17 |access-date=2019-11-24}}</ref><ref>{{Cite web |url=http://www.glaucoma.org/treating/a_new_type_of_g.html |title=Glaucoma Research Foundation - SLT: A New Type of Glaucoma Surgery |access-date=2006-10-11 |archive-date=2008-10-10 |archive-url=https://web.archive.org/web/20081010211845/http://www.glaucoma.org/treating/a_new_type_of_g.html |url-status=dead }}</ref> SLT shows promise as a long-term treatment.<ref>[http://www.revophth.com/index.asp?page=1_361.htm "Review of Ophthalmology: SLT for Glaucoma Threapy"] {{Webarchive|url=https://web.archive.org/web/20061017095343/http://www.revophth.com/index.asp?page=1_361.htm |date=2006-10-17 }} Selective Laser Trabeculoplasty</ref> In SLT a laser is used to selectively target the melanocytes in the trabecular meshwork.
Though the mechanism by which SLT functions is not well understood, it has been shown in trials to be as effective as the older ALT. However, because SLT is performed using a laser with much lower power than ALT, it does not appear to affect the structure of the trabecular meshwork (based on electron microscopy) to the same extent, so retreatment may be possible if the effects from the original treatment should begin to wear off, although this has not been proven in clinical studies. ALT is repeatable to some extent with measurable results possible.{{citation needed|date=January 2022}}
===Iridotomy=== An '''iridotomy''' involves making puncture-like openings through the iris without the removal of iris tissue. Performed either with standard surgical instruments or a laser, it is typically used to decrease intraocular pressure in patients with angle-closure glaucoma. A laser peripheral iridotomy (LPI) is the application of a laser beam to selectively burn a hole through the iris near its base. LPI may be performed with either an argon laser or Nd:YAG laser.<ref>[http://www.surgeryencyclopedia.com/La-Pa/Laser-Iridotomy.html Surgery Encyclopedia - Laser iridotomy]</ref><ref>{{cite web |title=EyeMDLink.com - Laser Peripheral Iridotomy (PI) |url=http://www.eyemdlink.com/EyeProcedure.asp?EyeProcedureID=46 |archive-url=https://web.archive.org/web/20061008110928/http://www.eyemdlink.com/EyeProcedure.asp?EyeProcedureID=46 |archive-date=2006-10-08 |access-date=2006-10-11}}</ref>
There is currently no sufficient evidence to show any benefit on the use of iridotomy versus no iridotomy to slow down visual field loss. This is based on analysing four studies with a sample of {{formatnum:3086}} eyes of {{formatnum:1543}} participants; iridotomy seems to improve gonioscopic findings, but does not show to be clinically significant.<ref name="Le">{{cite journal |vauthors=Rouse B, Le JT, Gazzard G |date=Jan 9, 2023 |title=Iridotomy to slow progression of visual field loss in angle-closure glaucoma |journal=Cochrane Database Syst Rev |volume=2023 |issue=1 |doi=10.1002/14651858.CD012270.pub3 |pmc=9827451 |pmid=36621864 |article-number=CD012270}}</ref>
===Iridectomy=== {{Main article|Iridectomy}} thumb|Eye after undergoing an iridectomy, with partial removal of the iris An iridectomy, also known as a corectomy or surgical iridectomy, involves the removal of a portion of iris tissue.<ref>[http://www.surgeryencyclopedia.com/Fi-La/Iridectomy.html Surgery Encyclopedia - Iridectomy]</ref><ref name="Cline">{{cite book |author1=Griffin, John W. |title=Dictionary of Visual Science |author2=Cline, David |author3=Hofstetter, Henry William |publisher=Butterworth-Heinemann |year=1997 |isbn=0-7506-9895-0 |edition=4th |location=Oxford}}</ref> A basal iridectomy is the removal of iris tissue from the far periphery, near the iris root; a peripheral iridectomy is the removal of iris tissue at the periphery; and a sector iridectomy is the removal of a wedge-shaped section of iris that extends from the pupil margin to the iris root, leaving a keyhole-shaped pupil.{{cn|date=December 2025}}
===Clear lens extraction=== {{Main article|Clear lens extraction}} Clear lens extraction, a surgical procedure in which clear lens of the human eye is removed, may be used to reduce intraocular pressure in primary angle closure glaucoma.<ref>{{cite web |date=28 October 2017 |title=Clear Lens Extraction: First-Line Treatment for Primary Angle-Closure Glaucoma? |url=https://www.aao.org/eyenet/article/clear-lens-extraction-for-pacg |website=American Academy of Ophthalmology |language=en}}</ref> A study found that CLE is even more effective than laser peripheral iridotomy in patients with angle closure glaucoma.<ref>{{Cite journal |last=Azuara-Blanco |first=Augusto |date=2011-05-23 |title=The effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle closure glaucoma: a randomised controlled trial (EAGLE) |journal=Trials |doi=10.1186/isrctn44464607 |pmid=21605352 |doi-access=free}}</ref><ref>{{Cite journal |last1=Tanner |first1=Luke |last2=Gazzard |first2=Gus |last3=Nolan |first3=Winifred P. |last4=Foster |first4=Paul J. |date=January 2020 |title=Has the EAGLE landed for the use of clear lens extraction in angle-closure glaucoma? And how should primary angle-closure suspects be treated? |journal=Eye |language=en |volume=34 |issue=1 |pages=40–50 |doi=10.1038/s41433-019-0634-5 |issn=1476-5454 |pmc=7002615 |pmid=31649349}}</ref>
===Goniotomy and trabeculotomy=== '''Goniotomy''' and '''trabeculotomy''' are similar simple and directed techniques of microsurgical dissection with mechanical disruption of the trabecular meshwork.<ref>{{EMedicine|oph|138|Glaucoma, Primary Congenital}}</ref><ref name="Aniridia">{{EMedicine|oph|317|Aniridia in the Newborn}}</ref> Goniotomy procedures include surgical goniotomy and laser goniotomy. A surgical goniotomy involves cutting the fibers of the trabecular meshwork to allow aqueous fluid to flow more freely from the eye.<ref name="emedh">{{Cite web |title=Primary Congenital Glaucoma |url=http://www.emedicinehealth.com/articles/38365-6.asp |archive-url=https://web.archive.org/web/20060308160344/http://www.emedicinehealth.com/articles/38365-6.asp |archive-date=2006-03-08 |access-date=2006-10-11}}</ref><ref>{{cite web |date=2012-08-20 |title=Glaucoma Surgery | Glaucoma Research Foundation |url=http://www.glaucoma.org/treating/surgical_treatm.html |access-date=2012-12-11 |publisher=Glaucoma.org |archive-date=2008-12-04 |archive-url=https://web.archive.org/web/20081204143041/http://www.glaucoma.org/treating/surgical_treatm.html |url-status=dead }}</ref><ref>[http://www.surgeryencyclopedia.com/Fi-La/Goniotomy.html Surgery Encyclopedia - Goniotomy]</ref> Laser goniotomy is also known as goniophotoablation and laser trabecular ablation.
In many patients with primary congenital glaucoma, the cornea is not clear enough to visualize the anterior chamber angle. Although an endoscopic goniotomy, which employs an endoscope to view the anterior chamber angle, may be performed,<ref>{{cite journal |vauthors=Joos KM, Shen JH, Ren Q |year=1994 |editor1-last=Parel |editor1-first=Jean-Marie A |editor2-last=Ren |editor2-first=Qiushi |title=Endoscopic goniotomy probe for holmium:YAG laser delivery |url=http://spiedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PSISDG002126000001000259000001&idtype=cvips&gifs=yes |journal=Proc. SPIE |series=Ophthalmic Technologies IV |volume=2126 |page=259 |bibcode=1994SPIE.2126..259J |doi=10.1117/12.178563 |s2cid=135831690 |url-access=subscription}}{{Dead link|date=November 2019 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> a trabeculotomy which accesses the angle from the exterior surface of the eye, thereby eliminating the need for a clear cornea, is usually preferred in these instances. A specially designed probe is used to tear through the trabecular meshwork to open it and allow fluid flow.<ref name=emedh/><ref>{{cite web |title=Video |url=http://webeye.ophth.uiowa.edu/eyeforum/video/Trab_03.wmv |archive-url=https://web.archive.org/web/20060922133229/http://webeye.ophth.uiowa.edu/eyeforum/video/Trab_03.wmv |archive-date=2006-09-22 |access-date=2006-10-11}}</ref>
===Tube-shunt surgery=== '''Tube-shunt surgery''' or '''drainage implant surgery''' involves the placement of a tube or glaucoma valves to facilitate aqueous outflow from the anterior chamber.<ref name=emedh/><ref>[http://www.surgeryencyclopedia.com/St-Wr/Tube-Shunt-Surgery.html Surgery Encyclopedia - Tube-shunt surgery]</ref><ref>{{cite web |last=Haddrill |first=Marilyn |title=Glaucoma Surgery - AllAboutVision.com |url=http://www.eyemdlink.com/EyeProcedure.asp?EyeProcedureID=45 |archive-url=https://web.archive.org/web/20080424105750/http://www.eyemdlink.com/EyeProcedure.asp?EyeProcedureID=45 |archive-date=2008-04-24 |access-date=2012-12-11 |publisher=Eyemdlink.com}}</ref> Trabeculopuncture uses a Q switched Nd:YAG laser to punch small holes in the trabecular meshwork.<ref>{{cite journal |vauthors=Epstein DL, Melamed S, Puliafto CA, Steinert RF |date=July 1985 |title=Neodymium: YAG laser trabeculopuncture in open-angle glaucoma |journal=Ophthalmology |volume=92 |issue=7 |pages=931–7 |doi=10.1016/S0161-6420(85)33932-5 |pmid=4022580}}</ref><ref>{{cite journal |vauthors=van der Zypen E, Fankhauser F |year=1979 |title=The ultrastructural features of laser trabeculopuncture and cyclodialysis. Problems related to successful treatment of chronic simple glaucoma |journal=Ophthalmologica |volume=179 |issue=4 |pages=189–200 |doi=10.1159/000308894 |pmid=121373}}</ref> '''Goniocurretage''' is an "ab interno" (from the inside) procedure that used an instrument "to scrape pathologically altered trabecular meshwork off the scleral sulcus".<ref name=Jacobi97/> A surgical cyclodialysis is a rarely used procedure that aims to separate the ciliary body from the sclera to form a communication between the suprachoroidal space and the anterior chamber.<ref name="Cline"/> A cyclogoniotomy is a surgical procedure for producing a cyclodialysis, in which the ciliary body is cut from its attachment at the scleral spur under gonioscopic control.<ref name="Cline"/>
===Ciliarotomy=== A ciliarotomy is a surgical division of the ciliary zone in the treatment of glaucoma.<ref name="Cline"/><ref>{{cite web |title=Yeshasvini.org |url=http://www.yeshasvini.org/html/SURGERY.pdf |access-date=2012-12-11 |publisher=Yeshasvini.org}}</ref>
===Canaloplasty=== Canaloplasty is an advanced, nonpenetrating procedure utilizing microcatheter technology to enhance the eye's natural drainage system. An incision is made into the eye to gain access to Schlemm's canal in a similar fashion to a viscocanalostomy. A microcatheter will circumnavigate the 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 the canal, the pressure inside the eye can then be relieved.
Canaloplasty has two main advantages of over more traditional glaucoma surgeries. The first of these advantages is an improved safety profile over trabeculectomy. As canaloplasty does not require the creation of a bleb, significant long-term risks such as infection and hypotony (extremely low eye pressure) are avoided. The second main advantage is that when combined with cataract surgery, the IOP is reduced even further than when done alone.<ref name="JCRS 3-year CP Results" />
Long term (three year) results have been published both in the US<ref name="JCRS 3-year CP Results">{{cite journal |last=Lewis |first=Richard A. |author2=Kurt von Wolff |author3=Manfred Tetz |author4=Norbert Koerber |author5=John R. Kearney |author6=Bradford J. Shingleton |author7=Thomas W. Samuelson |date=April 2011 |title=Canaloplasty: Three-year results of circumferential viscodilation and tensioning of Schlemm canal using a microcatheter to treat open-angle glaucoma |journal=Journal of Cataract and Refractive Surgery |volume=37 |issue=4 |pages=682–690 |doi=10.1016/j.jcrs.2010.10.055 |pmid=21420593 |s2cid=26495012}}</ref> and Europe<ref name="Canaloplasty 3-year European Results">{{cite journal |last=Bull |first=Holger |author2=Kurt von Wolf |author3=Norbert Körber |author4=Manfred Tetz |date=October 2011 |title=Three-year canaloplas ty outcomes for the treatment of open-an gle glaucom a: European study results |journal=Graefes Arch Clin Exp Ophthalmol |volume=249 |issue=10 |pages=1537–45 |doi=10.1007/s00417-011-1728-3 |pmid=21732110 |s2cid=22142101}}</ref> demonstrating a significant and sustained reduction in both eye pressure and the number of glaucoma medications required for glaucoma control.
==Procedures that decrease production of aqueous humor== thumb|Cyclocryotherapy (frozen spot visible) Certain cells within the eye's ciliary body produce aqueous humor. A ciliary destructive or cyclodestructive procedure is one that aims to destroy those cells in order to reduce intraocular pressure.<ref>{{cite web |title=Glaucoma | Oftalmología en Barcelona Imo.es |url=http://www.imo.es/en/patologia/glaucoma/ |archive-url=https://web.archive.org/web/20150409130517/http://www.imo.es/en/patologia/glaucoma/ |archive-date=April 9, 2015 |website=www.imo.es}}</ref>
Cyclocryotherapy, or cyclocryopexy, uses a freezing probe.<ref>{{cite web |title=Glaucoma Service Foundation to Prevent Blindness: Glaucoma Education: Cyclocryotherapy for Endstage Glaucoma |url=http://www.wills-glaucoma.org/cyclotherapy.htm |archive-url=https://web.archive.org/web/20060925140215/http://www.wills-glaucoma.org/cyclotherapy.htm |archive-date=2006-09-25 |access-date=2006-10-11}}</ref> Cyclophotocoagulation, also known as transscleral cyclophotocoagulation, ciliary body ablation,<ref name=emedh/> cyclophotoablation,<ref>{{cite journal |vauthors=Hamel P, Levin A |date=December 2003 |title=Glaucoma Surgical Techniques in Children: From Past to Future (Part 1 of 2) |journal=Techniques in Ophthalmology |volume=1 |issue=4 |pages=227–34 |doi=10.1097/00145756-200312000-00007}}</ref> and cyclophototherapy,<ref name=Aniridia/> uses a laser.<ref>{{cite web |title=EyeMDLink.com - Cyclophotocoagulation |url=http://www.eyemdlink.com/EyeProcedure.asp?EyeProcedureID=48 |archive-url=https://web.archive.org/web/20061111074314/http://www.eyemdlink.com/EyeProcedure.asp?EyeProcedureID=48 |archive-date=2006-11-11 |access-date=2006-10-11}}</ref>{{ref|Trabeculectomy}} Cyclodiathermy uses heat generated from a high frequency alternating electric current passed through the tissue,<ref name="Cline"/> while cycloelectrolysis uses the chemical action caused by a direct current.<ref name="Cline"/>
A systematic review seeking to assess the safety and effectiveness of diode transscleral cyclophotocoagulation found one study in Ghana comparing patients who received low-energy versus high-energy variations of the procedure to treat glaucoma.<ref name="Michelessi">{{cite journal |vauthors=Michelessi M, Bicket AK, Lindsley K |date=2018 |title=Cyclodestructive procedures for non-refractory glaucoma |journal=Cochrane Database Syst Rev |volume=2018 |issue=4 |doi=10.1002/14651858.CD009313.pub2 |pmc=6277057 |pmid=29694684 |article-number=CD009313}}</ref> Overall, the review found that 47% of eyes treated with transscleral cytophotocoagulation saw an IOP decrease of at least 20%.<ref name="Michelessi"/> There were no differences between the low-energy and high-energy variations of the procedure in all reported outcomes, such as IOP control, and number of medications used after treatment.<ref name="Michelessi"/> Another Cochrane Systematic Review explored whether cyclodestructive procedures are better than other glaucoma treatments for the treatment of refractory glaucoma; however, the evidence was inconclusive.<ref name="Chen">{{cite journal |author=Chen MF, Kim CH, Coleman AL |date=2019 |title=Cyclodestructive procedures for refractory glaucoma |journal=Cochrane Database Syst Rev |volume=10 |issue=3 |doi=10.1002/14651858.CD012223.pub2 |pmc=6409080 |pmid=30852841 |article-number=CD012223}}</ref>
== See also == * Minimally invasive glaucoma surgery * Eye surgery
==References== {{Reflist|30em}}
{{Eye procedures}}
{{DEFAULTSORT:Glaucoma Surgery}} Category:Eye surgery Category:Glaucoma