Polylactic Acid for Visualizing Vitreous Body During Vitrectomy

Abstract

Purpose:: To see the possibility of polylactic acid (PLA) as a surgical adjuvant for visualizing vitreous body during vitrectomy.

Methods:: After core vitrectomy, 1 mL of PLA suspension was injected into the rabbit vitreous; group A, 2.5% PLA (n=5), and group B, 1% PLA (n=9). Vehicle injection instead of PLA was used as a control (group C, n=5). The clinical signs and electroretinogram (ERG) were evaluated for 28 days and histological findings were also evaluated on day 28. Next, intraocular pressure (IOP) after intra-cameral injection of PLA suspension was evaluated in rabbits (n=6). Lastly, the visualization of vitreous body by PLA suspension was evaluated in vitrectomy for monkey eyes (n=4).

Results:: White granules of PLA disappeared from the vitreous cavity over time in 10 eyes within 3 weeks, however, small amount of PLA still remained in 4 eyes in 4 weeks. Mild inflammation of anterior chamber was observed in 1 eye of group B, and 1 eye of group C. No cataract, or retinal hemorrhage was found in any eyes. The amplitude of ERG on each time point did not differ between groups. IOP remained within normal range except for the initial spike. Retinal structure was well preserved histologically. During vitrectomy of monkey eyes, the vitreous body was well visualized and the posterior vitreous separation was performed easily and securely.

Conclusions:: PLA can be a new surgical adjuvant to visualize vitreous body during vitrectomy.

Keywords: vitreoretinal surgery • vitreous • vitreous substitutes