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Dexamethasone implants in retinal vein occlusion: 12-month clinical effectiveness using repeat injections as-needed
Lavnish Joshi1, Satish Yaganti, Maria Gemenetzi
1Department of Ophthalmology, Royal Surrey County Hospital NHS Foundation Trust, Guildford, Surrey, UK.
The British Journal of Ophthalmology
|May 21, 2013
Summary
The dexamethasone intravitreal implant offers visual acuity gains for retinal vein occlusion (RVO) but requires frequent retreatment. While effective, it has a shorter duration than expected and carries risks like increased intraocular pressure.
Area of Science:
- Ophthalmology
- Retinal Diseases
- Pharmacology
Background:
- Retinal vein occlusion (RVO) is a significant cause of vision loss.
- Macular edema is a common complication of RVO, leading to decreased visual acuity.
- Intravitreal corticosteroid implants are used to manage RVO-associated macular edema.
Purpose of the Study:
- To evaluate the 12-month outcomes of the dexamethasone intravitreal implant for RVO using an as-needed retreatment strategy.
- To assess visual acuity changes, macular edema resolution, and safety profile.
- To compare outcomes in branch RVO (BRVO) and central RVO (CRVO).
Main Methods:
- Retrospective case series of 51 eyes from 49 patients with RVO and macular edema.
- Patients received an intravitreal dexamethasone implant.
- Follow-up was conducted for at least 12 months.
Main Results:
- 70% of patients showed improvement within 3 months; 30% gained ≥15 letters.
- Mean VA letter score changes at 12 months: 5.7 (BRVO) and 11.5 (CRVO).
- 56% relapsed, with median relapse times of 17 (BRVO) and 18 (CRVO) weeks. Repeat injections had shorter durations (10 weeks).
- 27% experienced increased intraocular pressure; 4 eyes with CRVO developed neovascular glaucoma.
Conclusions:
- The dexamethasone implant's duration is shorter than 6 months, necessitating an as-needed retreatment protocol.
- Improved outcomes were observed with as-needed retreatment, especially in CRVO.
- Visual outcomes are comparable to triamcinolone (SCORE study), and neovascular complications persist in CRVO.
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