Leber Hereditary Optic Neuropathy (LHON) is a disease inherited from your mother. It causes you to lose your eyesight, starting with painless blurriness. Your central vision, which you need to drive, read and recognize faces, will be affected first. Symptoms typically start between the ages of 15 and 35. Eventually you may be legally blind.
Leber hereditary optic neuropathy (LHON), or sudden vision loss, is an inherited form of vision loss. It starts with a painless clouding or blurring in one or both eyes, and then worsens with a loss of sharpness and loss of color vision. LHON affects the central vision needed for detailed tasks such as reading, driving and recognizing faces. If you have LHON you might become legally blind.
LHON is a mitochondrial disease, which means it is only inherited through the mother. Individuals who have lost their central vision are referred to as “affected.” Individuals who carry one of the mitochondrial mutations but don’t experience vision loss are referred to as “carriers.”
Leber hereditary optic neuropathy is also sometimes called Leber’s optic atrophy or Leber’s optic neuropathy. It’s named after Dr. Theodore Leber, who studied the disease. LHON is hereditary – it’s passed down from parent to child. The word “optic” means eye, or vision. “Neuropathy” is the medical term for a disease of a nerve.
Leber hereditary optic neuropathy affects one in 50,000 people.
50% of males who have the LHON mutation and 85% of females never experience vision loss.
Most cases of Leber hereditary optic neuropathy are permanent. Around 95% of people with LHON may lose their vision before they turn 50.
Leber hereditary optic neuropathy typically starts when you’re a teenager or in your twenties. Rarely, someone will have the sudden vision loss as a child or later in adulthood.
Men are affected by LHON more often than women.
The onset of symptoms occurs between the ages of 15 and 35 years in most cases. However, ages of onset between two and 87 years have been reported.
Leber hereditary optic neuropathy starts with painless clouding and blurring of vision. The vision loss may start in one of your eyes, or in both. Typically you’ll see clouding and blurring in your unaffected eye after several weeks or months.
If you have the mutation in the mitochondrial DNA, this does not mean you will experience vision loss. Expression of the gene varies with the mitochondrial mutation. In most mutations, females have about a 15% chance and males have about a 50% chance of being affected. Some doctors believe that toxic substances may trigger the onset of blindness. It is suggested that people with a LHON mutation avoid certain substances including smoke, alcohol and paint fumes.
LHON is a genetic condition caused by a mutation in the mitochondrial DNA. It’s caused by mutations in the following genes:
Vision loss occurs because the cells in your optic (eye) nerve die. The optic nerve relays visual information from your eyes to your brain and once these cells die the optic nerve can no longer do its job effectively. Some studies have shown that smoking and drinking alcohol may contribute.
You may get LHON even though there are no other cases in your family.
LHON typically starts with painless, visual blurring that affects the central visual field in one eye. The other eye develops similar symptoms two to three months later. In about 25% of cases, both eyes develop vision loss simultaneously. As time goes on, you may lose sharpness of vision (visual acuity) and color vision.
In most cases, vision loss is the only symptom of LHON. However, a condition described as “LHON plus” sometimes occurs. Those additional symptoms include:
Leber hereditary optic neuropathy is a mitochondrial disease, which means you inherit it through your mother.
None. No foods or drinks affect LHON.
Classic Leber hereditary optic neuropathy is not painful. LHON-MS (multiple sclerosis) may include some eye pain.
Your healthcare provider will test your eyes and, if they suspect that your symptoms are caused by LHON, they can order a blood test to see if you carry a mitochondrial mutation.
As of now there is no cure for Leber hereditary optic neuropathy. However, some people may recover some (not all) of their sight. This is rare with the 11,778 mutation but more likely with the 3,460 and 14,484 mutations.
Currently, there is no approved treatment for Leber hereditary optic neuropathy. Taking vitamin C, vitamin E and vitamin B12 is sometimes recommended.
Regarding medications, a clinical trial of Idebenone, a synthetic form of Coenzyme Q10, has shown effectiveness in about half of the cases. Another treatment that shows promise is the Food and Drug Administration (FDA) approved EPI-743 drug. This drug is similar to Idebenone but contains a slight difference that may allow for increased vision recovery.
Continued research is needed in order to find a safe and effective treatment. Clinical trials are in progress. Experts are exploring hormone therapy, mitochondrial replacement and gene therapy.
There are support services available if you have LHON:
At this time there are no surgical treatments available.
No complications at this time.
If you have symptoms of Leber hereditary optic neuropathy, you should be monitored and helped by an ophthalmologist (eye care specialist) or neuro-ophthalmologist. If you have LHON plus, you’ll be monitored by a multidisciplinary team of healthcare providers who specialize in your eyes, heart and brain.
Unfortunately, you can’t avoid faulty genes inherited from your mother.
If you plan to be a mother, you can do some prenatal testing to determine the genetic risk of Leber hereditary optic neuropathy. Your healthcare provider may offer genetic counseling, which is where you’ll discuss the potential risks to your children. With that information you can make your family planning decisions.
No medications are known to prevent or reduce your risk of Leber hereditary optic neuropathy.
Individuals with LHON may have permanent vision loss. Once central vision loss occurs, you’ll typically not see any improvement in vision and can be considered legally blind. In some cases, individuals who suffered vision loss have an improvement of central vision within twelve months. However, this is rare and may depend on what type of LHON mutation the individual has.
In rare cases the vision has improved, but LHON never goes away.
Tell your friends and family about your symptoms and make them aware of your limitations and prognosis.
If you have problems with your vision, whether there’s a history of Leber hereditary optic neuropathy in your family or not, see your healthcare provider immediately. Do not wait to see if it gets worse.
A note from Cleveland Clinic
Leber hereditary optic neuropathy can be a devastating diagnosis. Legal blindness will change your life. Experts are working to find a treatment but, in the meantime, listen to your healthcare provider’s instructions and rely on your family, friends and service providers.
Last reviewed by a Cleveland Clinic medical professional on 02/26/2021.
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