Paediatric Ophthalmology focuses on the development of the visual system and various conditions that disrupt the visual development in children. Children may experience many different eye conditions such as:
- Amblyopia (lazy eye) – where the vision in one eye is significantly worse than the other eye
- Strabismus (squint)
- Blocked tear ducts
- Retinopathy of prematurity
- Refractive errors such as myopia (short-sightedness), hypermetropia (long-sightedness), and astigmatism
A paediatric ophthalmology examination generally includes:
- Visual acuity testing
- Stereoacuity testing (tests how well you perceive depth)
- Eye pressure testing
Generally, dilating drops are required to be instilled so that the Ophthalmologist can check the health of the retina (the back of the eye) with a special lens under a microscope. These eye drops cause blurred near vision and can sometimes take up to 24 hours or a few days to completely wear off.
What is strabismus and what causes it?
Strabismus (commonly referred to as ‘squint’) is a condition where the eyes are not aligned correctly. One eye may look straight ahead, where the other may turn inwards, outwards, upwards, or downwards. One eye may turn consistently or it may come and go.
Individuals with strabismus may experience double vision, reduced vision, decreased depth perception, or headaches. On the other hand, some people may not experience any symptoms at all.
Strabismus may be caused by a problem with the eye muscles, the nerves that transmit information to these muscles, or the control centres in the brain that directs information for eye movements.
Risk factors for strabismus include:
Family history – individuals with parents or siblings with strabismus are more likely to develop it.
Refractive Error – people with a significant amount of uncorrected hypermetropia (long-sightedness) or myopia (near-sightedness)
How common is strabismus?
Strabismus is a common eye condition among children, with approximately 3 – 5 percent of the Australian population affected by this condition.
How is strabismus treated?
It is important for strabismus to be detected and managed early to prevent vision loss associated with untreated strabismus. The principle of strabismus treatment is to improve the alignment of the eyes. Some management options include glasses, an eye patch to occlude the eye with better vision, or surgery.
Non-surgical strabismus treatment
Generally, ophthalmologists trial conservative treatment options with the aim of re-aligning the eyes. If a child is short-sightedness or long-sightedness, glasses may help to reduce the eye turn. Alternatively, eye exercises may be prescribed to strengthen or relax the eye muscles causing the eye turn. Stick-on prisms (known as Fresnel prisms) may also help to temporarily re-align the eyes and appreciate binocular single vision. These prisms can stick easily on glasses.
Surgical strabismus treatment
This method of treatment involves surgically operating on the eye muscle(s) that are causing the eye turn. The ophthalmologist typically either strengthens or relaxes the eye muscles during surgery to re-align the eyes.
This method is usually conducted in conjunction with eye exercises post-surgery to maintain the alignment of the eyes, allowing the individual to appreciate binocular single vision.
How is strabismus diagnosed?
A comprehensive eye examination is conducted to obtain a complete picture of how well your eyes work together. This typically includes:
Visual acuity testing
Alignment testing – this test will determine how well your eyes focus on an object and looks for any problems with the eyes being turned.
Slit lamp examination – the ophthalmologist will look at the back of the eye through a microscope to ensure that there are no underlying problems with the health of the back of the eye.
A common problem among children is the development and progression of short-sightedness. It can be important to control and prevent the progression of myopia as high levels of short-sightedness can lead to vision-threatening problems later in life – such as retinal detachment.
Short-sightedness can be caused by an eyeball that is too long. If this is the case, rays of light that enter the eye focus in front of the retina rather than directly on its surface, causing blurred vision when viewing objects that are further away. Additionally, children with parents who are short-sighted are more likely to develop myopia.
There are many options for preventing the progression of myopia, including Atropine eye drops, multifocal contact lenses or glasses, and orthokeratology (also known as Ortho K).
Atropine Eye Drops
Atropine eye drops prevent the progression of myopia by dilating the pupils and preventing a process known as accommodation (the eye’s natural ability to change focus for near vision). By effectively blurring near vision in children, the aim of Atropine is to slow the progression of short-sightedness.
Multifocal contact lenses or glasses
Multifocal contact lenses or glasses work by correcting short-sightedness. The glasses or contact lenses contain a segment for distance as well as near. The full prescription would be given for distance, whereas the near segment of the glasses or contact lenses would have a reduced prescription to relax the eye’s ability to focus at near.
Orthokeratology (Ortho K)
‘Ortho K’ is a type of myopia control that involves using corneal reshaping contact lenses. The contact lenses work by temporarily flattening the cornea (the front of the eye) and correcting the short-sightedness. These special lenses are only worn at night when the child is asleep and they are taken out in the morning. Studies have revealed that, over time, these contact lenses prevent the lengthening of the eyeball (which causes shortsightedness) by approximately 50%.