Editing Glaucoma (section)

====Laser-assisted nonpenetrating deep sclerectomy====
The most common surgical approach currently used for the treatment of glaucoma is trabeculectomy, in which the sclera is punctured to alleviate intraocular pressure.

Nonpenetrating deep sclerectomy (NPDS) surgery is a similar, but modified, procedure, in which instead of puncturing the scleral bed and trabecular meshwork under a scleral flap, a second deep scleral flap is created, excised, with further procedures of deroofing the Schlemm's canal, upon which, percolation of liquid from the inner eye is achieved and thus alleviating intraocular pressure, without penetrating the eye. NPDS is demonstrated to have significantly fewer side effects than trabeculectomy.<ref>{{cite journal | vauthors = Chiselita D | title = Non-penetrating deep sclerectomy versus trabeculectomy in primary open-angle glaucoma surgery | journal = Eye | volume = 15 | issue = Pt 2 | pages = 197–201 | date = April 2001 | pmid = 11339590 | doi = 10.1038/eye.2001.60 | doi-access = free }}</ref> However, NPDS is performed manually and requires higher level of skills that may be assisted with instruments<!-- to achieve a lengthy learning curve-->.{{Citation needed|date=May 2009}}   In order to prevent wound adhesion after deep scleral excision and to maintain good filtering results, NPDS as with other non-penetrating procedures is sometimes performed with a variety of biocompatible spacers or devices, such as the Aquaflow collagen wick,<ref>{{cite journal |url=https://www.reviewofophthalmology.com/article/making-the-case-for-nonpenetrating-surgery |title=Making the Case for Nonpenetrating Surgery|journal=Review of Ophthalmology| vauthors = Ahmed IK |volume=12|issue=9|date=1 September 2005}}</ref> ologen Collagen Matrix,<ref name="pmid23640614" /><ref>{{cite journal | vauthors = Aptel F, Dumas S, Denis P | title = Ultrasound biomicroscopy and optical coherence tomography imaging of filtering blebs after deep sclerectomy with new collagen implant | journal = European Journal of Ophthalmology | volume = 19 | issue = 2 | pages = 223–230 | year = 2009 | pmid = 19253238 | doi = 10.1177/112067210901900208 | s2cid = 22594085 }}</ref><ref>{{cite conference | vauthors = Matthew SJ, Sarkisian S, Nathan B, 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 |date=May 2012 |conference=ARVO |location=Ft. Lauderdale }}</ref> or Xenoplast glaucoma implant.<ref>{{cite web |vauthors=Anisimova SY, Anisimova SI, Larionov EV |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 |date=2012 |publisher=EGS Congress |location=Copenhagen |url-status=live |archive-url=https://web.archive.org/web/20131017051726/http://www.oic.it/~egscopenaghen2012/posters/june18/P2.24/poster.pdf |archive-date=17 October 2013 }}</ref>

Laser-assisted NPDS is performed with the use of a CO<sub>2</sub> laser system. The laser-based system is self-terminating once the required scleral thickness and adequate drainage of the intraocular fluid have been achieved. This self-regulation effect is achieved as the CO<sub>2</sub> laser essentially stops ablating as soon as it comes in contact with the intraocular percolated liquid, which occurs as soon as the laser reaches the optimal residual intact layer thickness.