Ophthalmic Case Study 4: Central retinal vein occlusion (CRVO)

 Patient History

HPI:

58-year-old Hispanic female administrative assistant complaining of decreased vision in the left eye. She first noticed this when she closed her right eye while removing makeup about 2 weeks prior to her visit. The vision in her left eye is still blurry and dark and may have worsened slightly. She occasionally experiences symptoms of dry eyes with burning, for which she uses artificial tears. She denies any pain, redness, double vision, flashing lights, or new floaters.

Past Ocular History:

Mild myopia, wears glasses. No history of ocular surgeries, amblyopia, strabismus, or eye trauma.

Ocular Medications:

Occasional use of artificial tears.

Past Medical History:

Menopause at age 51, history of pulmonary embolism 5 years ago after left foot surgery, hypertension under medication.

Surgical History:

Left foot surgery following trauma.

Family Ocular History:

Negative for macular degeneration, glaucoma, or blindness.

Social History:

Married, 2 children. Smokes ½ pack per day for 15 years. No alcohol or recreational drug use.

Medications:

Calcium supplement, multivitamin, hydrochlorothiazide, lisinopril.

Allergies:

None.

ROS:

Denies recent illness or any new CNS, cardiac, pulmonary, GI, skin, or joint symptoms.

Ocular Examination

Visual Acuity (cc):

OD: 20/25

OS: 20/200

IOP (tonometry):

OD: 21 mmHg

OS: 21 mmHg

Pupils:

Equal, round, and reactive to light, trace relative afferent pupillary defect (RAPD) in the left eye.

Extraocular Movements:

Full in all directions. No nystagmus.

Confrontation Visual Fields:

Full in OD for finger counting, inconsistent responses in OS.

External:

Normal on both sides.

Slit Lamp:

Eyelids and Lashes: Normal on both sides.

Conjunctiva/Sclera: Normal on both sides.

Cornea: Clear on both sides.

Anterior Chamber: Deep and quiet on both sides.

Iris: Normal in both eyes, no neovascularization.

Lens: +1 nuclear sclerosis in both eyes.

Anterior Vitreous: Clear on both sides.

Dilated Fundus Examination:

OD: Clear vision, CDR 0.5, with sharp optic disc margins; flat macula with normal foveal light reflex; slightly dilated retinal veins, mild arterial/venous nicking, normal peripheral retina.

OS: Edematous optic nerve with blurred margins; scattered intraretinal hemorrhages in all 4 quadrants, a few cotton-wool spots, macular thickening with loss of foveal light reflex, tortuous vessels.

Other:

OCT of the left eye - intra and subretinal fluid in the retina, distortion of normal foveal architecture.

Diagnosis and Discussion

Diagnosis:

Central retinal vein occlusion (CRVO) - Left eye.

Discussion:

Differential Diagnosis:

This patient experienced a central retinal vein occlusion (CRVO). Symptoms of sudden, painless vision loss and the appearance of "blood and thunder" retinal findings (as seen in the image) are typical of this diagnosis. Other conditions to consider include diabetic retinopathy, central retinal artery occlusion, anemia or leukemia-related retinopathy, or traumatic retinopathy.

Definition:

CRVO is the result of a blockage of the central retinal vein, likely at the level of the lamina cribrosa. Typical retinal findings include diffuse intraretinal hemorrhages, retinal edema, and dilated and tortuous retinal veins. Cotton-wool spots, optic nerve edema, hemorrhages, and subsequent development of iris, optic nerve, or retinal neovascularization may also be observed. CRVO can be classified into two main categories: perfused (the most common type) or ischemic/non-perfused. Generally, perfused CRVO is a milder form of the disease, with better visual acuity outcomes and lower likelihood of iris or retinal neovascularization compared to ischemic/non-perfused CRVO. However, up to one-third of perfused CRVO cases can progress to the ischemic form. Some patients present with an intermediate form that is difficult to categorize. Vision loss due to CRVO can be attributed to macular edema, macular ischemia, or complications of neovascularization, including neovascular glaucoma or vitreous hemorrhage.

Examination:

Risk factors for CRVO include systemic hypertension, diabetes mellitus, vasculopathy, and primary open-angle glaucoma. A typical patient is male and 50 years or older. A comprehensive medical history is necessary to identify any risk factors and assist in appropriate referral to a physician. Younger patients should also be evaluated for hypercoagulability states, other vascular diseases, and oral contraceptive use, in addition to the above. An initial ophthalmic examination may include fluorescein angiography to determine the degree of ischemia/perfusion—though interpretation is hampered by the amount of retinal hemorrhages. Monthly examinations should include visual acuity.