Esotropia is a rare optical condition wherein either one or both eyes are turned inwards. The medical terminology Esotropia is derived from the Greek language, in which “eso” means inward and “trope” translates to turn. Since individuals with esotropia appear to have crossed eyes, the disorder is frequently confused with lazy eye i.e. amblyopia.
However, the two are very different ailments – while amblyopia involves the incomplete development of one eye and the subsequent awkward external appearance, esotropia is a misalignment of the eyes with the eyeballs placed at an odd angle slanted towards the nose. In certain cases, esotropia develops right from childhood while at times, it is acquired later on in adult life.
Types Of Esotropia:
Depending on the age at which esotropia – a malady pertaining to eye misalignment i.e. strabismus occurs, it is classified into two types – infantile and acquired.
This type of esotropia develops right from childhood, in the first year of the baby’s life and the infant faces difficulties in using both eyes together.
Acquired esotropia affects a person in adult life, usually above the age of 20 and is triggered by various underlying ailments such as diabetes, farsightedness.
Another method of classifying instances of esotropia is the frequency with which the eyes are misaligned – constant and intermittent.
Constant Esotropia: In this type of esotropia, the eyes are positioned at an unusual angle sloping inwards all the time.
Intermittent Esotropia: Here, the misalignment of the eyes takes place only during specific situations, such as when the person is ill and while focusing on objects very near or very far away.
The most common type of esotropia is accommodative esotropia.
Accommodative Esotropia: Here, the misalignment of the eyes i.e. strabismus occurs only when the individual is attempting to focus on an object far away. Such persons generally have farsightedness and this type of inward-turned eye disorder is also referred to as refractive esotropia.
Many reasons induce esotropia and the eye disorder can develop at any age - early childhood, young adults and even in old age. The most common cause of esotropia is hereditary eye defects passed on in families. However, esotropia can also be instigated by pre-existing eye ailments like glaucoma, cataracts, as well as other chronic conditions like diabetes and hyperthyroidism i.e. overactive thyroid.
Certain illnesses in the brain, such as surplus fluid accumulation in the cerebral tissues, or insufficient amount of blood, oxygen, nutrients being transported to the brain – stroke, also prompt esotropia.
The typical symptoms associated with esotropia comprise:
- Either one or both eyes turned inwards
- Challenges in viewing objects clearly using both eyes, being able to focus only with one eye
- Crossed eyes like in amblyopia/lazy eye
- Problems gauging the depth of things and surfaces
- Blurred or double vision with an inability to see objects properly in 3 dimensions
The doctor specializing in eye disorders and vision-linked conditions – optometrist/ophthalmologist, thoroughly studies the eyes and visual ability of the patient. The complete medical history of the patient is recorded and the individual is also questioned about any family history of esotropia.
Eye examinations investigate the clarity of vision in one eye as well as both eyes of the patient, to look for any signs of crossed eyes or difficulty in seeing things using both eyes. Moreover, the functioning of the retina – the light-sensitive layer of the eyes, is carefully inspected to determine if light rays are being refracted to the right extent and in optimal directions, angles, besides checking for any indications of farsightedness.
The treatment for esotropia is based on how long the patient has had the condition, the severity of symptoms, if the distortion affects one or both eyes and if the individual suffers only from accommodative esotropia. The therapies involved in treating esotropia consist of:
Glasses/Contact Lenses: Glasses or contact lenses prescribed by the medical expert help to correct for the flawed assembly of the eyes or the defects in the retina such as farsightedness.
Vision Therapy: The healthcare provider also advises the patient to practice eye exercises, which aid in strengthening the eye muscles, improving blood circulation to the optic tissues and resolving vision problems in the affected eye with esotropia.
Botox Injections: In minor instances of esotropia, botox injections aid in realigning the eyes and focusing clearly on objects close by and placed at a farther distance.
Surgery: Surgical procedures are usually performed in cases of infantile esotropia, to alter the length of the eye muscles to resolve the misalignment, but in some situations, are also carried out in adults.