The visual function of a child matures gradually along with the general growth and development. Binocular vision develops with both the eyes contributing equally to the function. Image analysis maturation in the different areas of brain continues simultaneously.
There are situations where both the eyes do not develop to equal potential and one eye lags behind in function, the laggard eye is called-'Lazy Eye'. Technical expression for this condition is-'Amblyopia'.
The lazy eye can be pushed to perform to its potential by addressing the underlying cause at the earliest possible age. Good results are obtained before 6 years of age though efforts can be made in older age group but with lesser results. It is accepted that no improvement is expected after 10 years of age even with appropriate interventions.
What are the underlying conditions that cause Lazy Eye?
1. Uncorrected Difference in the refractive power of the two eyes.
This is known as 'anisometropic amblyopia'. Depth of amblyopia is proportionate to the difference in power between the two eyes. It is deeper in case of Hyperopic powers (plus power for distance) as compared to Myopic Powers.
2. Uncorrected Astigmatism
This is known as 'meridional amblyopia'.
3. Squint in the eyes
This is known as 'strabismic amblyopia'
4. Optical barrier to light going into an eye-cataract/droopy lid/lid growth etc
This is called 'stimulus deprivation amblyopia'
What is the Treatment?
1. Address the underlying cause first and foremost.
Prescription lenses, squint surgery, lid surgery, cataract surgery etc. In situations where the difference in power between the two eyes is more than 3.5 Dioptres use of contact lens becomes mandatory to avoid difference in image size between the two eyes.
2. Penalization of the better eye, which is suppressing the eye with poorer function.
You whip the lazy eye and restrain the suppressor eye. This is done mostly by using an eye patch or at times by using special cycloplegic eye drops. Penalization schedule has to be decided by the treating doctor and followed up periodically to gauge response.
What is the message?
1. Earliest diagnosis of Lazy Eye helps in treating it successfully. All pre school children must be examined once a year.
2. Lazy Eye can regain its potential completely with treatment
3. Oral intake of 'Citicoline' helps in treatment of Lazy Eye as well