Canaloplasty: Three-year results of circumferential viscodilation and tensioning of Schlemm canal using a microcatheter to treat open-angle glaucoma.

PURPOSE: To report 3-year results of the safety and efficacy of canaloplasty, a procedure involving circumferential viscodilation and tensioning of the inner wall of Schlemm canal to treat open-angle glaucoma. SETTING: Multicenter surgical sites. DESIGN: Nonrandomized multicenter clinical trial. METHODS: This study comprised adult open-angle glaucoma patients having canaloplasty or combined cataract-canaloplasty surgery. Qualifying preoperative intraocular pressures (IOPs) were at least 16 mm Hg with historical IOPs of at least 21 mm Hg. A flexible microcatheter was used to viscodilate the full circumference of the canal and to place a trabecular tensioning suture. Primary outcome measures included IOP, glaucoma medication use, and adverse events. RESULTS: Three years postoperatively, all study eyes (n = 157) had a mean IOP of 15.2 mm Hg ± 3.5 (SD) and mean glaucoma medication use of 0.8 ± 0.9 compared with a baseline IOP of 23.8 ± 5.0 mm Hg on 1.8 ± 0.9 medications. Eyes with combined cataract-canaloplasty surgery had a mean IOP of 13.6 ± 3.6 mm Hg on 0.3 ± 0.5 medications compared with a baseline IOP of 23.5 ± 5.2 mm Hg on 1.5 ± 1.0 medications. Intraocular pressure and medication use results in all eyes were significantly decreased from baseline at every time point (P<.001). Late postoperative complications included cataract (12.7%), transient IOP elevation (6.4%), and partial suture extrusion through the trabecular meshwork (0.6%). CONCLUSION: Canaloplasty led to a significant and sustained IOP reduction in adult patients with open-angle glaucoma and had an excellent short- and long-term postoperative safety profile. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned. Additional disclosures are found in the footnotes.

Canaloplasty: circumferential viscodilation and tensioning of Schlemm canal using a flexible microcatheter for the treatment of open-angle glaucoma in adults: two-year interim clinical study results.

PURPOSE: To evaluate 2-year postsurgical safety and efficacy of canaloplasty (circumferential viscodilation and tensioning of the inner wall of Schlemm canal) to treat open-angle glaucoma (OAG). SETTING: Multicenter surgical sites. METHODS: This international prospective study comprised adult OAG patients having glaucoma surgery or combined glaucoma-cataract surgery. Qualifying preoperative intraocular pressure (IOP) was at least 16 mm Hg and historical IOP, at least 21 mm Hg. The full circumference of the canal was viscodilated and a trabecular tensioning suture placed with a microcatheter. Primary outcome measures included IOP and glaucoma medication use. RESULTS: At 24 months, all 127 eyes (127 patients) had a mean IOP of 16.0 mm Hg +/- 4.2 (SD) and mean glaucoma medication use of 0.5 +/- 0.8 (baseline values 23.6 +/- 4.8 mm Hg and 1.9 +/- 0.8 medications). Eyes with canaloplasty alone had a mean IOP of 16.3 +/- 3.7 mm Hg and 0.6 +/- 0.8 medications (baseline values 23.2 +/- 4.0 mm Hg and 2.0 +/- 0.8 medications). Eyes with combined glaucoma-cataract surgery had a mean IOP of 13.4 +/- 4.0 mm Hg and 0.2 +/- 0.4 medications (baseline values 23.1 +/- 5.5 mm Hg and 1.7 +/- 1.0 medications). The IOP and medication use results at all time points were statistically significant versus baseline (P <.001). The late postoperative follow-up identified 3 patients with elevated IOP. No other serious ocular or nonocular complications were reported. CONCLUSION: Canaloplasty was safe and effective in reducing IOP in adult patients with OAG.

Canaloplasty: circumferential viscodilation and tensioning of Schlemm's canal using a flexible microcatheter for the treatment of open-angle glaucoma in adults: interim clinical study analysis.

PURPOSE: To evaluate the safety and efficacy of circumferential viscodilation and tensioning of the inner wall of Schlemm's canal in a new surgical procedure for the treatment of open-angle glaucoma (OAG). SETTING: Fourteen clinical sites in the United States and Germany. METHODS: In this international multicenter prospective study of adult patients with OAG having glaucoma surgery, patients with qualifying preoperative intraocular pressure (IOP) of at least 16 mm Hg or higher and open angles were eligible. Evaluation was performed at baseline and 1 day, 1 week, and 1, 3, 6, and 12 months preoperatively. After a nonpenetrating dissection technique to expose Schlemm's canal was performed, a flexible microcatheter (iTrack 250A, iScience Interventional) was used to dilate the full circumference of the canal by injecting sodium hyaluronate 1.4% (Healon GV) during catheterization. A suture loop was placed in the canal to apply tension to the trabecular meshwork. High-resolution ultrasound imaging was used to assess Schlemm's canal and anterior segment angle morphology, including distension of the trabecular meshwork caused by the tensioning suture. Data analysis was performed in 2 groups: Group 1, in which patients met all inclusion criteria, and Group 2, made up of Group 1 patients who had successful suture placement. RESULTS: Group 1 comprised 94 patients and Group 2, 74 patients. The mean baseline IOP in Group 1 was 24.7 mm Hg+/-4.8 (SD) on a mean of 1.9+/-1.0 medications per patient. In Group 2 (patients with sutures), the mean IOP was 16.1+/-4.7 mm Hg 3 months postoperatively, 15.6+/-4.0 mm Hg at 6 months, and 15.3+/-3.8 mm Hg at 1 year. Medication use dropped to a mean of 0.6+/-0.9 per patient at 12 months. Suture tensioning was an apparent contributing factor in achieving surgical success. Patients with measurable trabecular meshwork distension from suture tension had a mean IOP of 15.9+/-5.2 mm Hg at 6 months and 14.5+/-3.0 mm Hg at 12 months. Surgical and postsurgical adverse events were reported in 15 of 94 patients (16%) and included hyphema (3), elevated IOP greater than 30 mm Hg (3), Descemet's tear (1), hypotony (1), choroidal effusion (1), and exposed closure suture with eyelid edema and erythema epiphora (1); 4 patients were subsequently converted to trabeculectomy. CONCLUSION: Circumferential viscodilation and tensioning of Schlemm's canal was a safe and effective surgical procedure to reduce IOP in adult patients with OAG.