Preeclampsia is a complication during pregnancy characterized by high blood pressure, and signs of damage to other organ system--most often the kidneys. It usually begins after 20 weeks of pregnancy in women who previously had normal blood pressure. Even slight rises in blood pressure during this period of pregnancy can be a sign of preeclampsia. If left untreated, it can lead to severe consequences for both the mother and the developing fetus. Preeclampsia may affect as much as 3-5% of pregnancies and is a leading cause of maternal mortality.
Preeclampsia has a strong tendency for ocular complications. Some research indicates that as much as 25% of women with preeclampsia during pregnancy will have visual complications. While general vision changes, without other signs, are a cause for concern there are 3 specific ocular complications of preeclampsia that are must be ruled out during the eye exam of a pregnant female.
This condition is when the blood vessels in the retina have been affected in a number of ways. Since these blood vessels are important for supply blood, oxygen, and nutrients to the retina, hypertensive retinopathy is a concern. As many as 50% of women with preeclampsia will show a noticeable narrowing of the retinal arteries. Other complications of hypertensive retinopathy include retinal hemorrhages or areas of local infarcts (or isolated areas of lost oxygen supply). In most cases, treatment may not be indicated as hypertensive retinopathy in preeclampsia resolves soon after delivery. If more severe retinal vasculature complications are found, though, treatment may be indicated.
Serous Retinal Detachment
A serous retinal detachment occurs when blood or fluid from underlying tissues accumulate within a space under the retina and causes the retina to separate from the inside wall of the eye. The risk for retinal detachments is the permanent loss of vision. It’s estimated that only 1% of women preeclampsia may develop a serous retinal detachment.
Usually patients with this condition will present with a sudden loss of vision and the detachments are usually in both eyes. And although it can occur almost any time during pregnancy, a serous retinal detachment is most likely to occur before or soon after delivery. Typically, the treatment will be to control the underlying preeclampsia and spontaneous resolution may occur within a few weeks. In very severe preeclampsia there is, however, risk for permanent vision loss despite resolution of the detachment due to extensive damage to the cells of the retina.
This condition is when blindness occurs even though eye health and pupil function appears normal. It’s probably the most dramatic presentation of preeclampsia effects on vision. It may occur in as much as 15% of patients with severe preeclampsia. Some research suggests cortical blindness may be the first clinical symptom preceding seizures by several hours. The cause of cortical blindness may be due to vasospasm and injury to the brain. Or, it may be due to localized edema in the occipital cortex of the brain. In the latter case, the blindness is often reversible within 8 days.
Other eye and vision complications from preeclampsia have been noted in clinical studies. We recommend every pregnant patient diagnosed with preeclampsia or eclampsia undergo a full eye exam. And, in pregnant patient experiencing any vision or eye related problems, should notify their doctor immediately.