If you have had either of the laser surgeries for open angle glaucoma (Argon Laser Trabeculoplasty or Selective Laser Trabeculoplasty), you may still be a candidate for Canaloplasty. It depends, however, on how much scarring there is from the laser surgery. Although your surgeon can visually inspect the area around Schelmm’s canal using a special contact lens (a technique called gonioscopy), s/he cannot tell if there has been permanent scarring of the canal itself. It may not be possible to fully catheterize the canal if there is dense scarring of the canal (called stenosis). In that case, your surgeon would not be able to stent the canal open with a suture, but would still inject a special gel (called a viscoelastic) into the partially opened canal. When the canal cannot be fully cannulated and the stent is not placed, this is called viscocanalostomy. Although not as effective as canalopasty, it can still lower the IOP.