The latest article in our Clinical Practice series, “Retinal-Vein Occlusion,” comes from Dr. Tien Wong of the Singapore Eye Research Institute and the Centre for Eye Research Australia, and Dr. Ingrid Scott from the Penn State Hershey Eye Center.
Retinal-vein occlusion is a common cause of vision loss in older persons, and the second most common retinal vascular disease after diabetic retinopathy. In branch retinal-vein occlusion, the occlusion is at an arteriovenous intersection; in central retinal-vein occlusion, the occlusion is at or proximal to the lamina cribosa of the optic nerve, where the central retinal vein exits the eye.
• How does branch retinal-vein occlusion present?
Patients with retinal-vein occlusion typically present with sudden, unilateral, painless loss of vision. The degree of vision loss depends on the extent of retinal involvement and on macular-perfusion status. Some patients with branch retinal-vein occlusion report only a peripheral visual-field defect.
• What are the major risk factors for branch retinal-vein occlusion?
The strongest risk factor for branch retinal-vein occlusion is hypertension, but associations have been reported for diabetes mellitus, dyslipidemia, cigarette smoking, and renal disease.
Figure 1. Branch Retinal-Vein Occlusion in the Superotemporal Quadrant of the Right Eye.
Morning Report Questions
Q: What is the recommended management of a patient with branch retinal-vein occlusion?
A: The authors suggest that first-line treatment of branch retinal-vein occlusion is grid laser photocoagulation, since longer-term data from clinical trials have shown improvement in visual acuity, lower rates of adverse effects, and lower costs with this treatment than with anti-VEGF therapy. Grid, or focal, laser photocoagulation is used for the treatment of macular edema resulting from branch retinal-vein occlusion. Treatment with a dexamethasone implant is another option, but evidence is lacking to demonstrate an improvement in visual acuity beyond 3 months.
Q: What is the recommended management of a patient with a central retinal-vein occlusion?
A: Whereas macular edema resulting from branch retinal-vein occlusion is susceptible to treatment with grid laser photocoagulation, that resulting from central retinal-vein occlusion is not. Ranibizumab and bevacizumab are widely used in the treatment of central retinal-vein occlusion, as well as in the treatment of branch retinal-vein occlusion, and have been demonstrated to improve vision. The study of intravitreal injection of dexamethasone through an implant showed that the intervention improved vision in patients with central retinal-vein occlusion.