Abstract: Objective To observe the efficacy and safety of penetrating canaloplasty without viscoelastic for primary open angle glaucoma (POAG). Design Prospective case series. Participants 25 patients (35 eyes) with POAG penetrating canaloplasty without viscoelastic at Cangzhou Aier Eye Hospital from December 2021 to June 2022 were treated. Methods Record preoperative and postoperative intraocular pressure (IOP), number of anti-glaucoma drugs, LogMAR best corrected visual acuity (BCVA), average retinal nerve fiber layer (RNFL) thickness, vertical C/D, average gangline cell layer (GCL) thickness in the macular area, intraoperative and postoperative complications. Time points of follow-up were arranged at 1 day, 7 days, 1 month, 3 months, 6 months, and 1 year after the surgery. Complete success was defined as IOP ≤21 mmHg without any glaucoma medications. Qualified success was defined as IOP≤21 mmHg with glaucoma medications (within 2 types). Main Outcom Measures Rate of circumferential catheterization of the canal, IOP, surgical success rate, and intraoperative and postoperative complications. Results 33 eyes (94.3%) achieved the 360 degrees’catheterization of the canal without viscoelastic. All patients completed a 12 month follow-up, with an average preoperative IOP of (25.8±7.7) mmHg. The postoperative IOP at 1 day, 7 days, 1 month, 3 months, 6 months, and 1 year were (14.1±6.1), (13.3±4.9), (14.8±4.4), (15.0±4.8), (15.2±4.0) and (14.7±3.6) mmHg, respectively. There were statistically significant differences between the preoperative and postoperative IOP (all P<0.001). The complete success rate and qualified success rate at 1 year after surgery were 90.9% (30/33) and 97.0% (32/33), respectively. Conclusion The penetrating canaloplasty without viscoelastic is safe and effective for the treatment of POAG. Which has a significant short-term effect on reducing IOP. (Ophthalmol CHN, 2024, 33: 16-20)

Key words: expansion without viscoelastic, penetrating canaloplasty, primary open-angle glaucoma