From this article, canalsplasty appears to be a safe & effective alternative to trabeculectomy. Results if one study shows lowering of IOP from around 24mm Hg to around 16 mm Hg. This article concludes:
Dr. Tetz says he believes canaloplasty is a good choice as a replacement for trabeculectomy. “Overall, the pressure results of viscocanalostomy are comparable to those of trabeculectomy without mitomycin,” says Dr. Tetz, “but with a much lower risk of postoperative complications and much less intense care required immediately postop. So far, the results of canaloplasty are even better.”
J Cataract Refract Surg 2007;33:7:1217-1226.