Experimental circumferential canaloplasty with a new Schlemm canal microcatheter

AIM: To present a new, simple, inexpensive Schlemm canal microcatheter for circumferential canaloplasty in a rabbit model. METHODS: A rabbit glaucoma animal model was established by intravitreal injection of triamcinolone acetonide. Circumferential canaloplasty with a new Schlemm canal microcatheter(patent license number: 201220029850.0) was performed. The Schlemm canal microcatheter was composed of microcatheter wall and lumen. The wall was made of high refractive index plastic optical fiber that could be attached to an illuminant so that the whole lighted microcatheter was visible during circumferential canaloplasty. The lumen could be attached to an injector for injection of viscoelastic during catheterization. Rabbits were divided randomly into the control, model and treatment groups. Intraocular pressure(IOP) was measured with a Tono-pen tonometer pre-operation and 3, 7, 14, 21 and 28 d post-operation. Ultrasound biomicroscopy was performed to visualize the Schlemm canal microcatheter in the Schlemm canal and the sclera pool.RESULTS: The Schlemm canal microcatheter could be used to perform circumferential canaloplasty in the rabbit glaucoma animal model. IOP was lower in the treatment group than that in the model group 3, 7, 14 and 28 d after operation. There were no significant differences in IOP between the control group and treatment group. The differences among the three groups were statistically significant(3 d: F=41.985, P<0.001; 7 d: F=65.696, P<0.001; 14 d: F=114.599, P<0.001; 28 d: F=55.006, P<0.001).CONCLUSION: Circumferential canaloplasty is safe and effective in control of experimental glaucoma model in rabbits.