To observe the velocity of a falling IOFB in viscoelastic and the protection of viscoelastic to the retina during IOFB extraction.


1) The falling velocity of a stone, extracted from eye globe, weighted 0.02g, was respectively measured in normal saline and in sodium hyaluronate ;
2) In 12 eyes, before the IOFB was extracted, viscoelastic agent was injected on the surface of retina, to prevent possible damage to the retina due to falling IOFBs, or adjust the position of the IOFBs on the retina.


1) the falling velocity of the stone was 0.175m/s in normal saline, and 1.38×10-5 m/s in sodium hyaluronate;
2) In the 12 eyes, falling of different kinds of IOFBs did not make any signet on the retina with viscoelastic on it, and the position of the IOFBs could be adjusted so as to separate from the retina, which also resulted in facilitating the grasp of the IOFBs near the retina. Elevated IOP, injury of the retina or other related complications was not observed during or after the operations because of the procedure.


The falling velocity of an object is obviously slower in viscoelastic than that in normal saline; Injection of viscoelastic onto the posterior pole protected the retina from falling IOFB and facilitated the grasp of the IOFBs near the retina.



Xun Yang, Shu Du, Youyou Zha
Lixiang Eye Hospital of SoochowUniversity
Su Zhou
Email : dryangxun@163.com
Cell Phone: +8613982128299
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