Purpose of reviewThere is an increasing interest and availability of micro-invasive glaucoma surgery (MIGS) procedures. It is important that this increase is supported by sound, peer-reviewed evidence. This article will define MIGS, review relevant publications in the period of annual review and dis

Micro-invasive glaucoma surgery: current perspectives and future directions.

https://www.ophed.net/system/files/2012/11/1-s2.0-s0161642010007438-main-3591-3591.pdf

Randomized evaluation of the trabecular micro-bypass stent with phacoemulsification in patients with glaucoma and cataract.

Extracellular matrix in the trabecular meshwork.

https://www.mccormick.northwestern.edu/biomedical/markj/PDFofPapers/Johnson2006.pdf

What controls aqueous humour outflow resistance

Pressures in the juxtacanalicular tissue and Schlemm's canal in monkeys.

Aqueous outflow resistance of enucleated human eyes was measured at 7 and 25 mm Hg before and after partial and complete (12 clock hours) internal trabeculotomy. Following complete trabeculotomy, 71% of the resistance was eliminated at 25 mm Hg while only 49% was eliminated at 7 mm Hg. In contrast to published findings in eyes with intact trabecular meshwork where the resistance increased with increasing IOP (1), following complete trabeculotomy, the resistance decreased 2% per mm Hg with increasing IOP. Experiments with trabeculotomy limited to part of the circumference showed that a one hour trabeculotomy produced 41% (25 mm Hg) to 60% (7 mm Hg) of the effect of a twelve hour trabeculotomy. The results indicate that a surprisingly high fraction of aqueous outflow resistance resides in the distal aspects of the outflow system at normal IOP, and that this distal resistance drops as IOP is increased.

R Rosenquist

Papers

Outflow resistance of enucleated human eyes at two different perfusion pressures and different extents of trabeculotomy.