OCLUSION DE VENAS RETINALES

Teaching Topic
Retinal-Vein Occlusion
Clinical Practice
Retinal-Vein Occlusion
T.Y. Wong and I.U. Scott
     

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.
Clinical Pearls
  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.