• 20 Rare Eye Conditions That Ophthalmologists Treat

    Written By: Reena Mukamal
    Reviewed By: Ninel Z Gregori MD
    Oct. 22, 2020

    Ophthalmologists regularly care for eye conditions such as near- and farsightedness, cataracts and macular degeneration. But did you know ophthalmologists are uniquely qualified to study and treat uncommon eye diseases as well?

    A disease is “rare” if it affects fewer than 200,000 people in the United States. Many rare eye conditions have no treatment or cure. But through innovative research, ophthalmologists are discovering treatments for some of the most challenging eye diseases.

    Here are 20 rare diseases that ophthalmologists treat.

    Charles Bonnet syndrome:

    Up to 30% of people with severe vision loss in both eyes experience hallucinations. They may see geometric patterns or even people, animals or buildings that aren’t really there. Some might worry they’re losing their grip on reality, but that’s not the case. Patients usually know the images aren't real. These hallucinations may come and go for a year or two, then taper off. There’s no cure or treatment but it can help to switch environments by going from a light to a dark room, for example. It also helps to relax, move around or blink the eyes.
    Affects about 500 in 100,000 patients with vision problems.

    Hemolacria (bloody tears):

    Tears tinged with blood usually signal another underlying problem. Haemolacria may occur after a conjunctival injury, or from an object trapped under or inside the eyelid. Blood disorders like hemophilia, high blood pressure, nosebleeds or tumors in the eye are all possible causes. The exact cause must be narrowed down so that doctors can determine the best treatment.
    Extremely rare.

    Eye Conditions Passed Down the Family Tree

    Retinitis pigmentosa:

    People born with this genetic condition slowly lose vision as they age. It starts with trouble seeing at night or difficulty noticing details along the sides, or periphery, of their vision. As rods and cones in the retina slowly die, color vision fades and patients trouble seeing details directly in front of their eyes (central vision). Low vision tools and devices can help. There’s no cure. But ophthalmologists and other researchers are developing promising treatments ranging from gene therapies to retinal implants, sometimes called bionic eyes.
    Affects about 25 in 100,000 people.

    Usher syndrome:

    Retinitis pigmentosa is sometimes part of a broader condition called Usher syndrome that affects vision, hearing and balance. There is no cure for Usher syndrome or retinitis pigmentosa. But genetic therapies show promise for treating these inherited eye diseases.
    Affects up to 7 in 100,000 people.

    Stargardt disease (juvenile macular degeneration):

    Stargardt disease can go undetected until adolescence or adulthood, when people develop blurry or distorted vision. Vision loss can slowly decline to the level of legal blindness. This happens as light-sensing cells in the macula die off. The macula is the part of the retina that gives you central vision. Ophthalmologists and researchers are working hard to produce gene therapies and stem cell therapies for people with this condition.
    Affects up to 12 in 100,000 people.

    Retinoblastoma:

    Children younger than 5 are the group most likely to develop this cancer of the eye. Retinal cells undergo changes that spark uncontrolled cell growth, causing a tumor to form in one or both eyes. The cancer can spread to other parts of the eye and body. Children are at risk for other types of cancers in the bone, muscle, and skin. Because this cancer is inherited, the siblings and children of these patients may also be at risk of retinoblastoma. Early detection and treatment are key to preserving sight and saving the child’s life. Treatments include chemotherapy, laser therapy, cold therapy (cryotherapy) and surgery.
    Affects about 6 in 100,000 people.

    Best disease:

    This condition causes an egg-yolk-like residue to accumulate in the macula. By the time a patient reaches early adulthood, this buildup has damaged cells and distorted central vision. There’s not yet a treatment, but gene therapies and stem cell therapies may alleviate or cure this condition in the future.
    Affects about 6 in 100,000 people.

    Leber hereditary optic neuropathy:

    More men than women develop this eye disease. It often shows up in young adults with a telltale pattern: painless loss of central vision in one eye, followed months or years later by vision loss in the other eye. Ophthalmologists and scientists are evaluating genetic therapies and drugs that may help recover vision in these patients.
    Affects up to 7 in 100,000 people.

    Leber congenital amaurosis:

    Children with this disease can become blind before the age of one. That’s because light-gathering cells in the retina, known as rods and cones, do not work properly. A gene therapy called Luxturna can improve sight in patients with a defect in a gene called RPE65. But the condition can result from defects in more than two dozen other genes, and those defects cannot yet be corrected with gene therapies. Genetic testing can identify parents at risk of passing this condition on to their children.
    Affects up to 3 in 100,000 people.

    Batten disease (juvenile neuronal ceroid lipofuscinosis):

    Infants with Batten disease have a genetic defect that causes fatty substances to build up in cells of the brain, nervous system and retina. Vision loss occurs early, usually between ages five and 10, and ophthalmologists are often the first specialists to suspect a problem. Over time, Batten disease damages the brain and nervous system. There are different forms of the disease, but all are fatal. Doctors are still working on a treatment.
    Affects up to 4 in 100,000 people.

    Bietti’s crystalline dystrophy:

    Crystal deposits build up in the retina and cornea of affected children. These deposits accumulate over time. Eventually, the condition is detected when teens or young adults experience night blindness and trouble with central and side vision. People of Asian descent are most likely to develop this condition. There is not yet a cure or treatment.
    Affects about 1.5 in 100,000 people.

    Cystinosis:

    Multiple organs — including the eyes, brain, kidneys, liver and pancreas — are affected when crystal deposits containing the amino acid cystine accumulate. A medicine called cysteamine helps eliminate these deposits from the body. Cysteamine eye drops can remove crystal deposits from the cornea, improving light sensitivity and vision. Infantile cystinosis is the most common type of cystinosis, but the condition can also surface in children and adults.
    Affects fewer than 1 in 100,000 people.

    Eye Conditions That Can Be Detected at Birth

    Anophthalmia or microphthalmia:

    Infants with these conditions are born without an eye (anophthalmia) or with very small eyes (microphthalmia). This usually accompanies other health conditions. There’s no cure, but ophthalmologists can protect the child’s existing vision. An eye specialist called an ocularist can design non-seeing prosthetic eyes to enhance appearance. Patients also work with other eye care professionals, including experts in pediatrics, vitreoretinal disease, orbital and oculoplastic surgery and ophthalmic genetics.
    Affects about 10 in 100,000 infants.

    Coloboma:

    Coloboma means “curtailed” in Greek. When fetal eye development is interrupted during the first three months of pregnancy, infants are born with gaps of tissue missing from the eyelid, lens or other parts of the eye. Sometimes this is part of a broader genetic condition called CHARGE syndrome. Eyeglasses, contacts, eye patching, surgery and low vision devices can help protect sight.
    Affects about 10 in 100,000 infants.

    Axenfeld-Rieger syndrome:

    Various types of eye problems—from a thin iris to an off-center pupil—can affect people with this syndrome. In some cases, extra holes in the iris can give the appearance of multiple pupils. In other cases, the cornea is affected. About half of patients develop glaucoma and are at risk for serious vision loss. Glaucoma can be treated with eyedrops or surgery. Some patients experience glare or light sensitivity, and find relief with special lenses or contacts.
    Affects fewer than 1 in 100,000 people.

    Polycoria:

    People with “true” polycoria have two or more separate pupils in one or both eyes. Each pupil has its own sphincter muscle and they individually constrict and dilate. This can cause poor, dim or double vision. Surgery can help some people with true polycoria. Other patients have so-called “false” polycoria, where holes in the iris appear as two or more pupils, but only one actually works. These holes are usually just a defect of the iris and may cause some glare. Pseudopolycoria can affect patients with Axenfeld-Rieger syndrome, described above.
    Extremely rare.

    Eye Conditions of the Optic Nerve or Immune System

    Optic neuritis:

    Your eyes send visual information to the brain by way of the optic nerve. Swelling of this nerve can blur vision and make eye movement painful. Doctors don’t always know why this happens. Sometimes optic neuritis stems from an infection or an autoimmune disease such as neuromyelitis optica, described below. It can also be a side effect of certain medications. Optic neuritis is often treated with steroids.
    Affects about 115 in 100,000 people.

    Neuromyelitis optica (Devic disease):

    Vision loss and paralysis are two early symptoms of this autoimmune disease. Neuromyelitis optica sparks inflammation in the central nervous system, with swelling the optic nerve (known as optic neuritis, described above) and the spinal cord (known as myelitis). In most cases, initial symptoms improve with steroids or immune-suppressing drugs. But relapse can produce lasting vision loss and spinal cord damage, making it difficult to see or walk. More women than men develop this condition.
    Affects up to 10 in 100,000 people.

    Idiopathic intracranial hypertension:

    Pressure buildup in the brain and spinal cord can cause headachesdouble vision and even temporary blindness. Doctors don’t always know why this happens. Sometimes it occurs when fluid doesn’t drain properly from the brain. This condition is most likely to affect young, overweight women. It can also be a side effect of certain medications. Treatments include weight loss, a drug called acetazolamide or surgery to relieve pressure on the optic nerve.
    Affects up to 2 in 100,000 people.

    Behçet’s disease:

    This autoimmune disease affects many parts of the body, including the eye. Small blood vessels in the mouth, genitals, skin and eyes become inflamed and damaged. About 1 in 4 patients experience severe vision loss. Steroids and other medications can help calm inflammation and relieve symptoms.
    Affects fewer than 1 in 100,000 people in northern Europe and the United States; about 420 in 100,000 people in northern Turkey.