Abstract
Purpose :
To investigate the effects of paclitaxel associated to lipid nanoemulsions (LDE-PTX) upon postoperative scarring in rabbits undergoing trabeculectomy.
Methods :
Thirty-four New Zealand rabbits that underwent trabeculectomy were allocated to 4 groups: LDE-PTX/SC (n=9), treated with one intraoperative subconjunctival injection of LDE-PTX(1.5 mg); LDE-PTX/IV (n=9), treated with LDE-PTX (4mg/kg/day intravenously) at the end of the surgery and once a week for 3 weeks; MMC(n=9), treated with intraoperative 0.4 mg/mL mitomycin-C for 3 minutes; and control group (CTL, n=7), without treatment. Bleb characteristics, anterior chamber depth and intraocular pressure were evaluated over 4 weeks by a masked-observer. Bleb failure was defined when a flat, scarred, vascularized bleb was observed in association with a deep anterior chamber. Animals were sacrificed on day 28. Histologic analyses were performed to assess the amount of scarring and toxicity to the conjunctiva and ciliary body.
Results :
Groups were similar with respect to intraocular pressure and anterior chamber depth during the 28-day observation period. LDE-PTX/SC,LDE-PTX/IVand MMCgroups showed greater bleb height than controls on days 14 and 21 (p<0.01). The median survival times were 14, 21, 28 and 28 days for the CTL, LDE-PTX/IV, LDE-PTX/SC and MMC groups, respectively. LDE-PTX/SC, LDE-PTX/IV and MMC showed significantly longer bleb survival times than CTL (p<0.001). There were no significant differences in survival times among the 3 treatment groups (p>0.05). LDE-PTX/SC,LDE-PTX/IV and MMC were equally effective in reducing fibrosis (p<0.001), number of blood vessels (p<0.001) and chronic inflammatory cells (p<0.001) at the surgical site. However, LDE-PTX/SC and LDE-PTX/IV treatments had lower conjunctival and ciliary body toxicity (p<0.001) compared to MMC.
Conclusions :
Both LDE-PTX/SC and LDE-PTX/IV were effective in reducing the scarring process following trabeculectomy to the same extent as mitomycin C, but with considerably less toxicity to the conjunctiva and ciliary body. The novel preparation in both administration routes may offer promising results for wound healing modulation in the surgical treatment of glaucoma.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.