Visitec? I-Ring?預裝式虹膜擴張器(I-Ring?Pupil Expander)由聚氨酯材料制成，生物相容性好，不刺激眼內組織，無不適感。通過原手術切口由導入器送入眼內，利于自身彈性將瞳孔擴張成6.3mm的圓形，為手術提供充足的視野，擴張器與虹膜360°接觸，對瞳孔括約肌的拉力均勻，不會造成瞳孔括約肌因拉力不均產生的損傷，利于術后瞳孔恢復成圓形。

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