History
A direct review of systems toward the various systemic and local factors predisposing the central retinal vein occlusion (CRVO) is indicated.
Significant history includes the following:
-
Hypertension
-
Diabetes mellitus
-
Cardiovascular disorders
-
Bleeding or clotting disorders
-
Vasculitis
-
Autoimmune disorders
-
Use of oral contraceptives
-
Closed-head trauma
-
Alcohol consumption
-
Amount of physical activity
-
Primary open-angle glaucoma or angle-closure glaucoma
Ocular symptoms at initial presentation are as follows:
-
Asymptomatic
-
Decreased vision
-
Visual loss can be sudden or gradual, over a period of days to weeks. Visual loss ranges from mild to severe. Patients can present with transient obscurations of vision initially, later progressing to constant visual loss.
-
Photophobia
-
Painful blind eye
-
Redness of eyes
Ocular symptoms in later stages are as follows:
-
Decreased vision
-
Pain in the eyes
-
Discomfort
-
Redness
-
Watering
Physical
Patients with central retinal vein occlusion (CRVO) should undergo a complete eye examination, including visual acuity, pupillary reactions, slit lamp examination of the anterior and posterior segments, undilated examination of the iris, gonioscopy, fundus examination with indirect ophthalmoscope, and fundus contact lens. [13] Note the following:
-
Visual acuity: Best-corrected vision always should be obtained. It is one of the important indicators of the final visual prognosis.
-
Pupillary reactions may be normal and may present with relative afferent pupillary reflex. If the iris has abnormal blood vessels, the pupil may not react.
-
Conjunctiva: Advanced stages may show congestion on conjunctival and ciliary vessels.
-
Cornea: Advanced stages may show diffuse corneal edema obscuring the visibility of internal structures.
-
The iris may be normal. Advanced stages may show neovascularization. These vessels are detected best on an undilated iris. Initially, the vessels may be seen around pupillary margins and peripheral iridectomy openings if present.
-
The anterior chamber angle is examined by gonioscopy. This is examined best in an undilated iris. Initially, it may show neovascularization with open angles and later show total peripheral anterior synechia and closed angles.
-
Fundus examination: Retinal hemorrhages may present in all 4 quadrants. Hemorrhages can be superficial, dot and blot, and/or deep. In some patients, hemorrhages may be seen in the peripheral fundus only. Hemorrhages can be mild to severe, covering the whole fundus and giving a "blood and thunder appearance." Note the images below.
Fundus of a patient with nonischemic central retinal vein occlusion, showing few scattered peripheral fundus hemorrhages.
Recent onset central retinal vein occlusion, showing extensive hemorrhages in the posterior pole and giving the "blood and thunder appearance."
-
Dilated tortuous veins: Veins may be dilated and tortuous, as shown in the image below.
Patient with nonischemic central retinal vein occlusion presented with dilated, tortuous veins and superficial hemorrhages.
-
Optic disc edema: The optic disc may be swollen during the early-stage disease. Note the images below.
Central retinal vein occlusion showing significant disc edema with dilated tortuous veins and scattered retinal hemorrhages.
Fluorescein angiogram of the same patient with central retinal vein occlusion in as in previous image, showing leakage from disc, staining of retinal veins.
-
Cotton-wool spots are more common with ischemic CRVO. Usually, they are concentrated around the posterior pole. Cotton-wool spots may resolve in 2-4 months.
-
Neovascularization of the disc: Fine abnormal neovascularization of the disc (NVD) or within 1 disc diameter from the disc may be present. NVD indicates severe ischemia of the retina. NVD is sometimes difficult to differentiate from optociliary shunt vessels. NVD can lead to preretinal or vitreous hemorrhage.
-
Neovascularization elsewhere: Neovascularization elsewhere (NVE) is not as common as NVD. NVE indicates severe ischemia of the retina. NVE can lead to preretinal or vitreous hemorrhage.
-
Optociliary shunt vessels (depicted in the images below) are abnormal blood vessels on the disc, directing blood from retinal circulation to choroidal circulation, which indicates good compensatory circulation.
Fundus picture of a well-compensated, old central retinal vein occlusion showing optociliary shunt vessels.
Red-free photo of the same patient with central retinal vein occlusion as in the previous image, showing prominent optociliary shunt vessels.
-
Preretinal or vitreous hemorrhage
-
Macular edema with or without exudates
-
Cystoid macular edema
-
Lamellar or full-thickness macular hole
-
Optic atrophy
-
Pigmentary changes in the macula
Causes
Central retinal vein obstruction has been associated with various systemic pathological conditions, although the exact cause and effect relationship has not been proven.
Some of the conditions in which CRVO has been associated include the following:
-
Systemic vascular disease - Hypertension, diabetes mellitus, cardiovascular disease
-
Blood dyscrasias - Polycythemia vera, lymphoma, leukemia
-
Hypercoagulable state : COVID-19 [12]
-
Clotting disorders - Activated protein C resistance, lupus anticoagulant, anticardiolipin antibodies, protein C, protein S, antithrombin III
-
Paraproteinemia and dysproteinemias - Multiple myeloma, cryoglobulinemia
-
Vasculitis - Syphilis, sarcoidosis
-
Autoimmune disease - Systemic lupus erythematosus
-
Oral contraceptive use in women
-
Obstructive sleep apnea - This affects more patients with retinal vein obstruction than other disorders; treatment of the sleep apnea may help prevent central vein obstruction. [14]
-
Other rare associations - Closed-head trauma, optic disc drusen, arteriovenous malformations of retina
The Eye Disease Case-Control Study Group reported that the risk of CRVO is decreased in men with increasing levels of physical activity and increasing levels of alcohol consumption. The same study group reported a decreased risk of CRVO with the use of postmenopausal estrogens and an increased risk with higher erythrocyte sedimentation rates in women.
Complications
Ocular neovascularization is a potential complication. [15] Anterior segment neovascularization can lead to neovascular glaucoma. Posterior segment neovascularization can lead to vitreous hemorrhage.
Macular edema is another potential complication. [16, 17, 18] Macular edema is the common cause of decreased vision in CRVO, more so in the nonischemic type. It may resolve with good visual return. The patient may develop permanent degenerative changes with poor visual prognosis and may develop cystoid macular edema leading to lamellar or full-thickness macular hole.
Other potential complications include cellophane maculopathy and macular pucker, as well as optic atrophy.
Reported complications due to treatment with intravitreal injections include endophthalmitis, vitreous hemorrhage, and retinal detachment.
-
Recent onset central retinal vein occlusion, showing extensive hemorrhages in the posterior pole and giving the "blood and thunder appearance."
-
Peripheral fundus view of the same patient with central retinal vein occlusion as in the previous image, showing hemorrhages extending all over the fundus.
-
Fluorescein angiograph of same patient with central retinal vein occlusion as in previous images, showing hypofluorescence due to blockage from hemorrhages in the retina. It is not useful to perform a fluorescein angiogram in acute stages of the disease.
-
Fundus picture of the same patient with central retinal vein occlusion as in previous images, showing resolving neovascularization of the disc and panretinal photocoagulation scars.
-
Fluorescein angiogram of the same patient with central retinal vein occlusion as in the previous images, taken more than 1 year later, showing persistent cystoid macular edema with good laser spots.
-
Patient with nonischemic central retinal vein occlusion presented with dilated, tortuous veins and superficial hemorrhages.
-
Fundus picture of the same patient with central retinal vein occlusion as in previous image, showing resolved hemorrhages and pigmentary changes in the macula several months later.
-
Central retinal vein occlusion showing significant disc edema with dilated tortuous veins and scattered retinal hemorrhages.
-
Fluorescein angiogram of the same patient with central retinal vein occlusion in as in previous image, showing leakage from disc, staining of retinal veins.
-
Fundus of a patient with nonischemic central retinal vein occlusion, showing few scattered peripheral fundus hemorrhages.
-
Scattered retinal hemorrhages in a patient with central retinal vein occlusion.
-
Fluorescein angiogram of a patient with nonischemic central retinal vein occlusion, showing staining of dilated tortuous veins with leakage into macula in a cystoid pattern.
-
Fluorescein angiogram of the same patient as in previous image, showing perifoveal capillary leakage in a cystoid pattern in late phases of angiogram.
-
Late phase of fluorescein angiograph of the same patient as in previous image, showing cystoid pattern of leakage from perifoveal dilated leaking capillary network.
-
Arteriovenous phase of fluorescein angiograph showing perifoveal capillary leakage in a patient with nonischemic central retinal vein occlusion.
-
Fundus picture of a well-compensated, old central retinal vein occlusion showing optociliary shunt vessels.
-
Red-free photo of the same patient with central retinal vein occlusion as in the previous image, showing prominent optociliary shunt vessels.
