Hemianopia is when a person experiences a partial loss of visual field in either or both of their eyes. Sometimes the visual field is reduced to half or a quarter of its normal size. This may occur as a result of disease, including multiple sclerosis or brain tumor. A related condition called strabismus causes one or both eyes to be misaligned, either inward or outward.
Hemianopia
The term hemianopia is used to describe the condition in which a person has blindness in the right or left half of their visual field. This condition is often caused by damage to the optic nerves or a stroke. There are several types of hemianopia, each affecting a different part of the visual field. Hemianopia occurs most frequently in people who have suffered a stroke.
A person who suffers from hemianopia often struggles with spatial orientation and may bump into things on their impacted side. They may even be unable to understand the reasons why they cannot drive due to their loss of vision. To compensate for this, they may develop a compensating strategy that involves exploring the right or left side of a room and writing down the size of the space.
A doctor can detect hemianopia during a routine eye exam. A visual field exam will determine how the eyes focus. Other tests, such as air bursts, may also be used to check the health of the brain. Regardless of the underlying cause of the condition, the tests will determine if there is a neurological cause of the blindness.
Leber’s congenital amaurosis
Leber’s congenital amauroses is an inherited retinal disease that affects approximately one in 40,000 newborns. This type of blindness usually occurs during the first six months of life and is characterized by severely reduced vision, sluggish pupillary responses, nystagmus, and photophobia. This condition has been linked to at least 25 different genetic mutation variants. Typically, Leber’s congenital amaurosis results in substantial vision loss.
During the early stages of the disease, the outer segments of rods and cones are missing. Because the rods are affected, the retinal nerve cells are not able to produce the necessary amount of retinol. This causes the rods and cones to cluster in the periphery and sprout neuritis.
The disease may be inherited as a dominant or recessive disorder. While inherited LCA is a hereditary condition, the symptoms are similar in many other forms of blindness. Generally, the disease is inherited in a recessive pattern from each parent, with the risk of development of LCA as a result of carrying one of the recessive alleles from both parents.
Stellate neuroretinopathy
If you’re experiencing visual or neurological symptoms, you may be suffering from a condition known as neuroretinitis. This disease affects the retina and contiguous nerve cells. Symptoms can be mild or severe, and it has a wide range of causes. It’s best to seek a medical professional’s diagnosis in order to find a treatment option.
This disease is characterized by vascular inflammation of the optic nerve and can be triggered by direct invasion or by autoimmune activation. It can also develop secondary inflammatory changes, such as edema in the nerve fiber layer of the retina. Treatment for this condition depends on whether the disease is progressive or reversible. Although there is no cure for stellate neuroretinopathy, it is possible to slow its progression with laser treatment.
A diagnosis of stellate neuroretinopathy should be made with the help of a qualified health professional. The disease is inherited through autosomal recessive inheritance, which means a child born to two carriers of an abnormal gene has a 25 percent chance of inheriting the disease. This condition may result in blindness, loss of acuity, or photophobia.
