What is it?

It is difficult to focus or sustain focus at near distances. Symptoms may include: blurred near vision, double vision, frontal headaches, rubbing eyes, reduced attention in the classroom or at work. The problem may be ‘primary’ or ‘secondary’ to an underlying medical condition.

What is the cause?

There are multiple causes for this condition. A lack of switching the focus of the eye from far distance to nearby objects (or vice versa), which can happen with patients who are long sighted or short sighted. Poor general health such as after viral infections or trauma to the eye can cause focussing problems, as can certain medications such as antidepressants or an underlying medical condition.

Children with Down’s syndrome and Cerebral Palsy have a high chance of a poor or reduced ability to switch focus between long and short distances. Sometimes an underlying problem may have gone unnoticed  and an increase in the amount of detailed close work or a change in work i.e. more computer work may cause the underlying problem to become more noticeable.

How is it treated?

This depends on what is causing the problem. If there is an underlying medical condition that is unmanaged, this will need to be assessed. Glasses may be issued if there is an underlying need for them or accommodative exercises may be given by the Orthoptist. The exercises aim to relieve symptoms. The Orthoptist will advise on the best type of exercises and the frequency for each individual patient.

What is it?

The tear duct (also known as the nasolacrimal duct) is a small passage that runs from the inner corner of the eyelids to the inside of the nose. A blocked tear duct is where the passage is obstructed or not yet opened.

What is the cause?

Blocked tear ducts are common in new born babies and can occur in adults too. It is thought one in five babies are born with a tear duct that is not yet open in one or both eyes. This can cause excessive watering and in some cases sticky mucus. In adults a blocked tear duct may be due to an injury, an age related infection and/or tumours.

How is it treated?

In new-borns the condition usually gets better without  treatment during the first year of life. At times the skin around the eyes may become sore due to the constant wetness. Occasionally conjunctivitis may develop (red inflamed eyes) which may require antibiotic drops.

You may be asked to massage the area under the eyelids to help the tear duct to open. If the symptoms persist after the age of one year, an operation can be performed to help the opening the tear duct.

What is it?

A blow out or orbital fracture is a fracture in the bones surrounding the eyeball. Symptoms of an orbital fracture will depend on what kind of fracture it is and how severe the injury is, but can include blurry vision, double vision, difficulty in moving your eyes, bruising, swelling, numbness, red eye, bulging or sunken eye and pain.

What is the cause?

Orbital fractures are caused by a sudden increase in pressure around your eyes. This can arise from blunt trauma either from an object striking the face, for example a fist, or through being thrown against a hard surface such as in a road traffic accident. A break in the very thin bone that makes up these walls can pinch muscles and other structures around the eye.

How is it treated?

Treatment for a blow out fracture will be determined by the maxillofacial surgeons and you may require surgery urgently. Double vision can often resolve on its own as the soft tissue swelling reduces. If it persists treatment is usually in the form of Fresnel prisms applied to glasses or occlusion (covering one eye). Surgery may also be performed on the eye muscles to increase the range of movement or balance the defect if required, however the outcome of this can be unpredictable.

What is it?

Brown’s syndrome is a type of eye movement condition that can affect one or both eyes looking upwards and inwards towards the nose. It is usually present at birth but can occur later in life. It tends to affect the right eye and occurs more often in females than males.

What is the cause?

There are six muscles that allow the movement of each eye. In Brown’s Syndrome, the abnormality involves the superior oblique muscle or its tendon. The muscle travels through a cartilage structure to produce an upwards movement of the eye. In Brown’s syndrome there is usually an problem with this structure causing a restriction of the ability to look upwards and inwards.

How is it treated?

Most people with Brown’s syndrome have no problems in their daily life and often no treatment is required. Children who are identified with the condition may require monitoring to ensure vision develops normally. In rare cases where a patient is struggling with double vision or is having to hold their head in an extreme position in order to manage daily tasks, a specialised squint operation may be considered.

What is it?

Good convergence is required to maintain comfortable single vision for near viewing. Convergence insufficiency is a condition in which a patient struggles to move both their eyes towards the nose at the same time. Symptoms include: blurred vision, double vision, eye strain and frontal headaches. The problem may be ‘primary’ or ‘secondary’ to an underlying medical condition.

What is the cause?

There a multiple possible causes for the condition; Poor general health such as after viral infections or trauma to the eye can cause problems with convergence as can a significant knock to the head. Certain medications such as antidepressants or an underlying medical condition are known to make a problem with convergence worse. Sometimes an underlying problem may have gone unnoticed  and an increase in the amount of detailed close work or a change in work i.e. more computer work may make the underlying problem more noticeable.

How is it treated?

It depends entirely on the underlying cause of the problem. If there is an underlying medical condition that is unmanaged then this will need to be assessed. Glasses may be issued if there is an underlying need for them or convergence exercises may be given by the Orthoptist. The exercises aim to relieve symptoms. The Orthoptist will advise on the best type of exercises and the frequency for each individual patient.

What is it?

This is an eye condition which is present from birth. It will cause the affected eye to have restricted eye movement when looking to the sides. You may also notice changes to the eyelid position; widening and narrowing.

The condition can affect one or both eyes. Females are more likely to be affected than males, and the left eye is the most commonly affected eye.

What is the cause?

There are six muscles that allow the movement of each eye and three nerves that control these muscles. In Duane’s syndrome it is thought that the nerves are not connected correctly, causing information to travel from the brain to the incorrect muscles.

How is it treated?

Most people with Duane’s syndrome have no problems in their daily life and often no treatment is required. Those children identified with the condition may require monitoring to ensure vision develops normally. In rare cases where a patient is struggling with double vision or is having to hold their head in an extreme position in order to manage daily tasks, a specialised squint operation may be considered.

What is it?

Ocular nerve palsies are characterised by a decrease or complete loss in function of one or more cranial nerves (in the brain). The third, fourth and sixth cranial nerves are responsible for eye movements. Loss of function of one or more of these nerves will result in a squint, and eye movement problems will develop. Double vision may be the first sign of this. Nerve palsies may be present from birth (congenital) or develop later in life (acquired).

What is the cause?

The most likely cause of a nerve palsy is damage to the nerve, caused by impaired blood flow or wound. Common causes of this are: diabetes, high blood pressure, high cholesterol, viral infections, migraines, swelling of blood vessels, or trauma.

How is it treated?

This depends on the underlying medical condition. It is possible for nerve palsies to recover partially or fully over time. The underlying cause of the nerve palsy will indicate how likely this is.

If double vision is present following the nerve palsy, this will be managed by the orthoptic and ophthalmology team. Double vision may be treated with Fresnel prisms (optical aid), occlusion (covering one eye) or surgery to the eye muscles in specific cases.

What is it?

Nystagmus is a repetitive, rhythmic, involuntary movement of the eyes. 1 in every 1500 people have a form of nystagmus. The movement of the eyes can be side to side, up and down, in a circular motion, or a combination of these. Individual's with nystagmus do not see as clearly, and there may be quite a difference in vision between different people with nystagmus. Others may notice your eyes ‘wobbling’ when they are talking to you, and at times the wobble may be more noticeable.

Nystagmus may be from childhood (congenital) or you may develop it in later life (acquired).

What is the cause?

Congenital nystagmus may be caused due to abnormal development of the eye, brain, or visual pathway connecting the eyes and the brain. Some forms of nystagmus can be inherited but in some cases the cause is unknown. When the cause is unknown the nystagmus is termed idiopathic.

Acquired cases are rare but may be caused by a stroke or head injury.

How is it treated?

It is not possible to cure nystagmus, the care is focussed on making the best of an individual’s vision levels. Thankfully nystagmus does not get worse but can vary and in some cases glasses or contact lenses may help to improve vision. Medication can be prescribed to reduce the involuntary movement of the eyes, however it is not possible for everyone. The effects are temporary and would need to be discussed with your doctor. Often in congenital cases there is a ‘null point’ where the eye movement is at its finest and allows the best vision. This often results in having to hold the head at an awkward angle to achieve the best vision. Sometimes the eyes can be operated upon to reduce the awkward head posture (angle).

What is it?

A pseudo-squint is the appearance of a squint (a turn of the eye), but the eyes are in fact straight.

What is the cause?

The most common cause of an appearance of a squint are prominent folds of skin around the eyes (epicanthus) which may be asymmetric. This is often associated with a flat bridge of the nose. These elements together give the impression one eye is turning in, particularly when looking to the side.

Other causes of this may be eyes set close together or asymmetry of the eyelids.

How is it treated?

No treatment is required as the eyes are in fact aligned, typically the appearance of the squint improves over time as the child’s face grows and develops.

What is it?

Ptosis is a drooping of the upper eyelid. It typically affects one eye, but it can affect both eyes. Ptosis can be present either from birth (congenital) or acquired in later life (acquired).

In some patients it may cause a cosmetic problem, but in others it may interfere with vision by affecting the top part of the peripheral vision. It may cause eye strain or eyebrow ache due to increased effort needed to raise the eyelid using other muscles.

What is the cause?

Congenital ptosis is commonly caused by a defect in the muscle that lifts the eyelids (levator muscle).

In Marcus Gunn ‘jaw-winking’ ptosis, the droopy eyelid temporarily lifts when the jaw is opened due to an abnormal connection of the nerves involved. This condition only affects one eyelid and is often only noticed in young children.

Acquired ptosis affects people in later life and may be due to a weakness of the eyelid muscle due to ageing, or a rare condition such as Myasthenia Gravis, or a problem with the nerve supply to the eyelid, or a cyst or swelling of the eyelid.

How is it treated?

Childhood ptosis needs to be monitored as it may impact on visual development, particularly if the eyelid covers the pupil (centre of the eye). If this is the case surgery may be required. Surgery would also be the treatment option for older children and adults.

What is it?

This is a term used to describe when light reaching the back of the eye is poorly focussed, causing poor vision. This is potentially due to genetic factors.

There are 4 main types:

Hypermetropia (long-sighted) - can affect vision at all distances but near vision is much worse.

Myopia (short-sighted) - mainly impacts distance vision.

Astigmatism – affects both distance and near vision equally.

Anisometropia – a  significant difference in focussing between the two eyes.

What is the cause?

It is not always clear why individual’s develop the need for glasses. It is thought there are many reasons such as a mixture of genetic and environmental factors combined. Children who are born low birth weight (less than 5lb), born premature, children who have additional needs or have treatment for retinopathy (damaged blood vessels in the back of the eye) of prematurity(born before 37 weeks) in the first few weeks of life are more likely to develop a need for glasses.

How is it treated?

The treatment is to correct the focussing problem optically with either glasses or (if old enough to tolerate) contact lenses. Laser eye surgery may be an option for some but is not available on the NHS to correct a focussing problem.

What is it?

Thyroid eye disease (TED) is an eye condition that causes the muscles and soft tissues in and around your eye socket to swell. Symptoms include:

• eyes feeling dry and gritty
• sensitivity to light
• watery eyes
• blurred or double vision
• bulging eyes
• red, swollen or pulled back eyelids
• eye movement problems
• reduced colour and reduced contrast vision

You are at a higher risk of having TED if you are female, if you are a smoker, or you are middle aged.

What is the cause?

Thyroid eye disease is mainly associated with an overactive thyroid gland due to Graves’ disease, although it does sometimes occur in people with an under-active or normally functioning thyroid. Graves' disease is an autoimmune disorder that causes hyperthyroidism (overactive thyroid gland). The thyroid is a small butterfly-shaped gland in the neck, just in front of the windpipe (trachea). It produces hormones that affect things such as your heart rate and body temperature. This means your immune system attacks the thyroid gland and causes it to make more thyroid hormone than your body needs. The period of inflammation and swelling caused by TED is known as the "active" stage. This generally resolves on its own over a period of about six months to two years. After this, the inflammation settles, this is known as the "inactive" or "burnt out" stage.

How is it Treated?

The aim of treating Thyroid Eye Disease is to correct any thyroid gland dysfunction.  Treatments such as medicine, radioactive iodine treatment or surgery may be offered. For smokers, stopping smoking is an effective way to improve symptoms.

Possible treatments to help with eye symptoms:

• Dry / gritty eyes – are treated with artificial tears in the form of eye drops
• Double vision – Prisms (specialised glasses) / occlusion (covering one eye) / surgery
• Eyelid surgery to ensure they are protecting your eyes
• Orbital decompression surgery (removing parts of the eye socket bones to relieve pressure or improve the bulging of the eyes) – if your optic nerve is at risk of being compromised this may be required urgently