Diagnosis: Central Retinal Vein Occlusion (CRVO)
CRVO is the most common retinal vascular disease after diabetic retinopathy and occurs when the central retina vein becomes occluded. It is believed to follow Virchow’s Triad of clotting risk factors. OtherIn addition to this, risk factors include advanced age, HTN, HLD, DM2, OCP, increasedraised ICP, and smoking. Furthermore, conditions that can increase hypercoagulability, such as malignancy, can also increase the risk for CVRO. It is typically characterized by sudden onset, painless vision loss.
There are 2 types of CRVO: Non-ischemic CRVO vs. Ischemic CRVO. The prognosis differs based on the type of CRVO. Non-ischemic CRVO has a relatively good prognosis with return to normal or near-normal vision being 50%. However, chronic macular edema can complicate this prognosis. In general, those who had better visual acuity to start with will have better outcomes in vision returning. In contrast, visual prognosis in ischemic CRVO is often poor due to irreversible ischemic damage. Furthermore, it may increase the risk for neovascularization due to increased levels of VEGF the setting of ischemia.
In particular, iris neovascularization and neovascular glaucoma can develop, more often in the case of ischemic CVRO, and patients should be closely monitored for this complication,. This often occurs with the first 90 days after the CRVO and is therefore referred to as the “90 day glaucoma.” Panretinal photocoagulation should be performed after neovascularization development as preferred treatment.
CRVO is typically treated with intravitreal anti-VEGF injections. These help to reduce to VEGF drive and can help to improve macular edema. Panretinal photocoagulation can also be performed, but is not utilized as frequently with the advent off intravitreal anti-VEGF injections. Additionally, intravitreal steroids may be considered in refractory cases.
References and Additional Resources:
- Shah V, Tripathy K., et al, Central Retinal Vein Occlusion . Hsu J (Eds). American Academy of Ophthalmology: EyeWiki. April 2022.
- Shah V, Randolph J, et al, Retinal Vein Occlusion . Hsu J (Eds). American Academy of Ophthalmology: EyeWiki. April 2022, https://eyerounds.org/article/CRVO.
- Hayreh S Central Retinal Vein Occlusion . University of Iowa Healthcare. August 2016
- Alasil, T., Lee, N., Keane, P. et al. Central retinal vein occlusion: a case report and review of the literature. Cases Journal 2, 7170 (2009). https://doi.org/10.1186/1757-1626-2-7170.