Related Experiment Video
Updated: May 14, 2026
06:19
Intracameral Injection in Rats with Low Risk of Adverse Effects
Published on: May 31, 2024
Bevacizumab-loaded polyurethane subconjunctival implants: effects on experimental glaucoma filtration surgery
Jayter Silva Paula1, Vanessa Raquel Coimbra Ribeiro, Fernando Chahud
1Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, School of Medicine of Ribeirão Preto-University of São Paulo, Ribeirão Preto, São Paulo, Brazil. jspaula@fmrp.usp.br
Summary
A novel bevacizumab-loaded polyurethane implant (BPUI) was developed for glaucoma surgery. While short-term release limited bleb impact, BPUIs effectively reduced vascular endothelial growth factor (VEGF)-expressing fibroblasts.
Area of Science:
- Ophthalmology
- Biomaterials Science
- Vascular Biology
Background:
- Glaucoma filtration surgery can lead to scarring, potentially mediated by vascular endothelial growth factor (VEGF).
- VEGF promotes fibroblast proliferation, a key factor in scar tissue formation.
- Novel drug delivery systems are needed to manage post-surgical scarring in glaucoma patients.
Purpose of the Study:
- To develop and characterize a bevacizumab-loaded polyurethane implant (BPUI) as a novel anti-VEGF drug delivery system.
- To evaluate the efficacy of BPUIs in a rabbit model of glaucoma filtration surgery.
- To assess the impact of BPUIs on scarring and VEGF expression post-surgery.
Main Methods:
- Polyurethane films were fabricated and loaded with bevacizumab (1.5 mg).
- Bevacizumab-loaded (BPUI) and control (PUI) implants were surgically placed in rabbit eyes.
- In vitro drug release (HPLC) and in vivo effects on bleb characteristics, collagen deposition, and VEGF expression were analyzed.
Main Results:
- In vitro studies showed limited bevacizumab release (10% by day 5).
- In vivo analysis revealed no significant differences in bleb area or collagen between BPUI and PUI groups.
- The BPUI group exhibited a significantly lower proportion of VEGF-expressing fibroblasts compared to the PUI group (0.17±0.03 vs. 0.35±0.05 cells/field, P=0.005).
Conclusions:
- Bevacizumab release from BPUIs was primarily short-term, likely from the implant surface.
- The BPUIs were well-tolerated in rabbit eyes.
- Despite limited release, BPUIs demonstrated a reduction in VEGF-expressing fibroblasts, suggesting potential anti-scarring benefits.
Related Concept Videos
01:27Open Angle Glaucoma: Treatment
In open-angle glaucoma, the iridocorneal angle remains open, but the trabecular meshwork becomes stiff, slowing down the outflow of aqueous humor. This causes a buildup of aqueous humor in the anterior chamber, leading to a sudden increase in intraocular pressure. The treatment for open-angle glaucoma focuses on reducing the elevated intraocular pressure by either decreasing the secretion of aqueous humor or increasing its outflow.
Drugs such as carbonic anhydrase inhibitors, α2- and...
Drugs such as carbonic anhydrase inhibitors, α2- and...
01:28Angle Closure Glaucoma: Treatment
Angle-closure glaucoma, or closed-angle glaucoma, is an eye condition where the iris bulges out and blocks the iridocorneal angle, resulting in a buildup of aqueous humor and increased intraocular pressure. Immediate medical attention is necessary due to the sudden onset of symptoms. The treatment for angle-closure glaucoma includes short-term and long-term approaches. Short-term treatment involves using eye drops like pilocarpine to lower intraocular pressure by increasing aqueous humor...