title: Paclitaxel-Releasing Thin Biodegradable Film for Prevention of Bleb Avascularity Without Compromising Filtration in Rabbits.
abstract: OBJECTIVE
  A honeycomb-patterned film (HPF) prevents bleb scarring and mitomycin C (MMC)-related bleb avascularity in a rabbit model of filtration surgery. In this study, we examined whether a HPF-releasing paclitaxel (PTX) can prevent bleb avascularity without compromising filtration.
  
  
  METHODS
  Filtration surgery was performed in one eye of rabbits. A 14-μm thick HPF made from poly(L-lactide-co-ε-caprolactone) was placed subconjunctivally over the filtration site with the honeycomb surface turned toward the subconjunctival Tenon tissue. The rabbits were divided into four groups (n= 5 each): 1, HPF with no drug; 2, HPF + PTX 50 μg; 3, HPF + 5 μg; 4, HPF + 0.5 μg. Intraocular pressure (IOP) measurements and bleb evaluations using ultrasound biomicroscopy were performed periodically for 4 weeks followed by histological examination. A longer follow-up study (12 weeks) was performed for group 4 (experiment 2;n= 8).
  
  
  RESULTS
  Among all groups at the 4-week follow up, two blebs failed in group 1. The postoperative IOP decrease was significantly greater in PTX-treated eyes than in group 1. The bleb avascular area persisted for 4 weeks in groups 2 and 3. However, no avascular area was observed in groups 1 and 4 at 4 weeks postoperatively. Histology showed minimal fibrosis at the filtration site in all the PTX groups. In experiment 2, some blebs became flatter starting at 10 weeks after surgery.
  
  
  CONCLUSIONS
  PTX released from HPF promoted bleb survival and IOP decrease. The lowest dose of PTX (0.5 μg) was effective at preventing bleb avascularity without compromising filtration.
authors.affiliation: Department of Ophthalmology Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Tetsuhiko
authors.initials: T
authors.lastname: Okuda
authors.affiliation: Department of Ophthalmology Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Tomomi
authors.initials: T
authors.lastname: Higashide
authors.affiliation: Department of Ophthalmology Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Sakurai
authors.affiliation: Research Laboratories III, Integrative Technology Research Institute, New Business Development Group, Teijin Limited, Tokyo, Japan.
authors.forename: Yukako
authors.initials: Y
authors.lastname: Fukuhira
authors.affiliation: Research Laboratories III, Integrative Technology Research Institute, New Business Development Group, Teijin Limited, Tokyo, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kaneko
authors.affiliation: Department of Bio- and Material Photonics, Faculty of Photonics Science and Technology, Chitose Institute of Science and Technology, Chitose, Japan.
authors.forename: Masatsugu
authors.initials: M
authors.lastname: Shimomura
authors.affiliation: Department of Ophthalmology Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Sugiyama
keywords: avascular bleb; drug delivery; honeycomb-patterned film; trabeculectomy