A new clinical trial is underway to evaluate whether combining vitrectomy surgery with intravitreal dexamethasone implants can improve outcomes for patients with proliferative diabetic retinopathy (PDR) requiring surgical intervention.
The single-masked, randomized controlled trial will enroll 100 participants diagnosed with PDR who require vitrectomy surgery. Participants will be randomly assigned to receive either standard vitrectomy alone or vitrectomy plus a 0.7 mg dexamethasone intravitreal implant (Ozurdex).
"Poor visual outcomes after vitrectomy are commonly caused by macular edema and proliferative vitreous retinopathy," explains the research team. "While intravitreal dexamethasone has shown promise for diabetic macular edema, its role specifically in PDR vitrectomy remains unexplored."
Study Design and Methods
The trial will follow participants for 24 weeks post-surgery, with evaluations at baseline and weeks 4, 8, 12, and 24. A single surgeon will perform all vitrectomy procedures to ensure consistency. The dexamethasone implant will be administered at the end of surgery before closing the scleral wounds in the treatment group.
Primary outcome measures include:
- Corrected visual acuity at 12 weeks post-treatment
- Changes in macular morphology
- Rate of postoperative complications
Secondary endpoints encompass:
- Retinal reattachment rates
- Central macular thickness on OCT
- Incidence of elevated intraocular pressure
- Rate of postoperative vitreous hemorrhage
- Need for subsequent cataract surgery
Patient Safety and Monitoring
The research team has established clear criteria for discontinuing participation, including:
- Need for repeat surgery
- Development of uncontrolled glaucoma
- Severe inflammatory complications
- Implant dislocation requiring removal
Statistical analysis will utilize repeated measures ANOVA for visual acuity and OCT measurements, while chi-square tests will evaluate categorical outcomes like complication rates. The study is powered to detect clinically meaningful differences with 93% statistical power.
Clinical Significance
"This study addresses an important gap in current PDR management," notes the research team. "By evaluating both visual and inflammatory outcomes in a diverse patient population, we hope to determine if this combination approach can improve surgical success rates and patient outcomes."
The trial is registered with the Chinese Clinical Trial Registry (ChiCTR2200059760) and is being conducted at Tongren Eye Center. Results are expected to provide valuable insights into optimizing surgical management of advanced diabetic eye disease.
