Nystagmus is a condition where the eyes move rapidly from side to side or up and down. It cannot be controlled but does often change in severity throughout the day. Nystagmus is relatively common and affects between 2-3 per 1,000 people in the UK.Nagini Sarvananthan, Mylvaganam Surendran, Eryl O. Roberts, Sunila Jain, Shery Thomas, Nitant Shah, Frank A. Proudlock, John R. Thompson, Rebecca J. McLean, Christopher Degg, Geoffrey Woodruff, Irene … Continue reading
Nystagmus can affect people in a variety of ways. The main symptom of nystagmus is a rapid and uncontrollable movement or shaking of the eyes. The shaking of the eyes can also be associated with the shaking of vision (oscillopsia). If nystagmus has been present from birth (congenital) then it is less likely to cause oscillopsia. However, if the nystagmus presents later in life (acquired) then oscillopsia is almost universal.Straube A, Bronstein A, Straumann D. Nystagmus and oscillopsia. European Journal of Neurology. 2012;19(1):6-14.
Sometimes when this happens it can make a patient feel dizzy or nauseous. Nystagmus can also affect the quality of the vision and so it may cause a reduction in visual acuity. If this happens from a young age, then it can affect the nerve connections between the eye and the brain which can lead to poor visual development (amblyopia).https://www.aao.org/disease-review/amblyopia-types-diagnosis-treatment-new-perspectiv (accessed 27/1/21).
Nystagmus can be categorised in a variety of different ways. Straube A, Bronstein A, Straumann D. Nystagmus and oscillopsia. European Journal of Neurology. 2012;19(1):6-14. However one of the most important differences between types of nystagmus is whether it is early onset/childhood nystagmus or acquired/adult onset. This is because the age of onset of nystagmus helps to determine the cause as well as the potential treatments.
A small amount of nystagmus in certain situations is normal and can be brought on by looking as far as possible to one side or even by pouring cold water in the ear!  https://www.uptodate.com/contents/overview-of-nystagmus (accessed 27/1/21).People also demonstrate a form of nystagmus whilst looking through a window of a fast-moving car or train. These types of nystagmus are called physiological nystagmus and are completely normal. https://www.uptodate.com/contents/overview-of-nystagmus (accessed 27/1/21).
Early onset nystagmus begins before the age of 6 months. It can be inherited or it can be caused by other factors such as a congenital cataract causing poor vision. Sometimes there is no cause found and this type of nystagmus is called idiopathic. Because the brain of a child is very adaptable many patients with early onset nystagmus have good functional vision throughout their life.
Late onset nystagmus can have a variety of causes which should be investigated. The causes can include a stroke, multiple sclerosis, drinking a lot of alcohol or as a side effect of taking certain medications such as those used for the treatment of epilepsy or depression.https://www.aao.org/eyenet/article/making-sense-of-acquired-adult-nystagmus (accessed 27/1/21).
Some forms of nystagmus are harmless and do not need investigating. In other forms of nystagmus it is clear from the history what the cause is and so they also do not need investigating. However, if the doctor is not able to work out what is causing the nystagmus then it can be important to investigate. This often involves blood tests as well as a brain scan (MRI or CT).
A lot of nystagmus does not need treatment because it does not significantly affect the vision. This is particularly true in early onset forms of nystagmus. However nystagmus sometimes needs to be treated because it can cause other problems such as blurred vision or a painful neck because some patients twist their neck to minimise the eye shaking.
There are several different treatments which can successfully be used to treat nystagmus. Each method has advantages and disadvantages. It is important to discuss the options with your doctor as the right treatment can depend on many factors such as what the cause of the nystagmus is and if you have any other medical conditions.
A common way to treat nystagmus is often with oral medications. These are more commonly used in adults. The more common medications are memantine, gabapentin and baclofen.McLean RJ, Gottlob I. The pharmacological treatment of nystagmus: a review. Expert Opin Pharmacother. 2009 Aug;10(11):1805-16.
Some patients benefit from special glasses with high prescriptions or prisms which bend the light before it enters the eye. Another simple option to treat nystagmus in one eye if it is interfering with the vision in the other eye is simply to occlude the eye with a patch, opaque glasses or a contact lens.
Nystagmus can also be treated with surgery which is often used in early onset nystagmus. The surgery is directed at the muscles around the eyeball and aims to move the eye into a position where the nystagmus is minimised.Cham KM, Abel LA, Busija L, Kowal L, Bachar Zipori A, Downie LE. Surgical interventions for infantile nystagmus syndrome. Cochrane Database Syst Rev. 2019;2019(8):CD013390. Published 2019 Aug 5. … Continue reading This can also be achieved temporarily with an injection of Botox into the space around and behind the eye.
Can patients with nystagmus have laser eye surgery?
Many patients with nystagmus can still have laser eye surgery.Soloway BD, Roth RE. Laser in situ keratomileusis in a patient with congenital nystagmus. Journal of Cataract & Refractive Surgery. 2002;28(3):544-546. This will depend on what the cause of the nystagmus is and how severe it is. It is important to know that the laser eye surgery does not treat the nystagmus and only treats the cornea (the front of the eye) to improve vision without the use of glasses or contact lenses. However some patients report that the symptoms of nystagmus improve after having laser eye surgery.Mahler O, Hirsh A, Barequet IS, Kremer I, Marcovich AL, Levinger S. [Lasik in myopic patients with congenital nystagmus]. Harefuah. 2006 Mar;145(3):183-5, 247. Hebrew. PMID: 16599312. It can even be possible to have more advanced forms of laser eye surgery such as SMILE.11. https://crstodayeurope.com/articles/performing-smile-in-a-patient-with-high-astigmatism-and-nystagmus/performing-smile-in-a-patient-with-high-astigmatism-and-nystagmus-2/ (accessed 27/1/21).