Visitec® I-Ring®预装式虹膜扩张器(I-Ring®Pupil Expander)由聚氨酯材料制成，生物相容性好，不刺激眼内组织，无不适感。通过原手术切口由导入器送入眼内，利于自身弹性将瞳孔扩张成6.3mm的圆形，为手术提供充足的视野，扩张器与虹膜360°接触，对瞳孔括约肌的拉力均匀，不会造成瞳孔括约肌因拉力不均产生的损伤，利于术后瞳孔恢复成圆形。

[1] Rio D, Woog, Legras R, Effect of age, decentration, aberrations and pupil size on subjective image quality with concentric bifocal optics [J].Ophthalmic Physiol Opt,2016,36(4):411-20.

[2]Artal P,Marcos S,lglesias l,et al.Optical modulation transfer and contrast sensitivity with decentered small pupils in the human eye [J].Vision Res,1996,36(22):3575-86.

[3] Ajasse S, Benosman RB, Lorenceau J. Effects of pupillary responses to luminance and attention on visual spatial discrimination [J].J Vis,2018,18(11):6.

[4] AndersonHA, Ravikumar A, Benoit JS, et al. Impact of Pupil Diameter on Objective Refraction Determination and Predicted Visual Acuity  [J]. Transl Vis Sci Technol,2019,8(6):32.

[5].Knorz MC, Koch DD, Martinez-Franco C, et al. Effect of pupil size and astigmatism on contrast acuity with monofocal and bifocal intraocular lenses [J].J Cataract Refract Surg,1994,20(1):26-33.

[6] Xu R, Kollbaum p, Thibos L, et,al. Reducing starbursts in highly aberrated eyes with pupil miosis [J]. Ophthalmic Physiol Opt,2018,38(1):26-36.