Primary Infantile Esotropia
Primary infantile esotropia is the inward deviation of one or both eyes. It usually begins at birth or early in life when the part of the brain that controls the ability to use the two eyes together does not develop completely. Despite the many hypotheses made, the real cause remains unknown. Can present:
- Abnormal head position
- Hyperfunction of Small Oblique Muscles in 70% of Cases
- Disassociated Vertical Deviation (DVD) in 75% of Cases
Therapy For Esotropia
The main treatment of this type of strabismus is surgical. Standard surgery involves the recession (weakening) of the medial muscles of both eyes. In a mono-lateral deep amblyopia, one-sided surgery may be performed with a recessive medial muscle recession associated with a rectal muscle resection (reinforcement) of the amblyopia eye. If oblique small muscles are hyper-functional, they can be recessed at the same time. It is recommended to intervene after two and a half years of age, to have a somewhat stable angle of deviation. At times, injection of type A botulinum toxin into the medial rectus muscles can be effective.
Accommodative Esotropia is the most common type of strabismus, resulting in a hyperactivity of the convergence reflection associated with accommodation. It is a converging strabismus type caused by the strain that the eyes make to see in focus. Children with this form of strabismus are hypermetropic. This means that the eyes must exercise a great amount of effort to see sharply, especially close. A side effect of accommodation is convergence. Therefore, in general, the greater the hypermetropia, the greater the accommodative effort and the risk of developing the esotropia. However, not all affected by hypermetropia become squinters. Some are, in fact, more sensitive to the accommodative effort. In most cases, it is entirely due to a hypermetropic refractive defect and refractive accommodative esotropia, where the total correction of the defect detected in cycloplegia resolves the strabismus with a total recovery of the binocular vision. It usually rises to 2-3 years when the accommodation is mature.
The basic treatment is the prescription of wearing glasses. The prescription must correct the entire refractive defect. The eyeglass relaxes the child’s accommodative effort and the eyes can straighten. It is normal for the eyes to continue to converge without glasses. Sometimes strabismus can also be more visible than before, but only when the baby is without glasses. The important thing is that the child’s eyes are straight when glasses are worn. In cases where there is a minor angle esotropia, we refer to it as partially accommodative esotropia, whose treatment involves the prescription of glasses and the recessive surgery of the medial muscles of both eyes to correct the residual angle. Surgery is only indicated when the eyeglasses do not straighten the eyes to help improve the eye alignment. In general, surgery does not eliminate the need to wear glasses but solves the strabismus that is still present with wearing eyewear.
Accommodative esotropia from an altered relationship between accommodative convergence and accommodation
A particular type of accommodative esotropia is the accommodative esotropia from the altered relationship between accommodating and accommodating convergence (AC / A). These children are affected by the excessive convergence of the eyes when they focus on nearby objects and their eyes are perfectly straight when they focus on a distant object. These children can benefit from a bifocal glasses to have their eyes even when focusing on nearby objects.
Transcription of the video.
Esotropia means the convergence of strabismus so the eyes point to the nose, one or both eyes. Esotropia can be infantile, the one that rises in the very first years of age when both eyes can be crooked. In that case, what can be done is to surgically operate the baby after two years of age for safety issues, to be more secure. The other most frequent case of esotropia is the accommodative esotropia. It is the case that is fortunately totally corrected by the use of glasses. Without the eyeglasses, the child will have crooked eyes to the nose. It will be possible to completely correct the strabismus with the use of glasses. The other strabismus is the partially accommodative esotropia. In this case, the eyeglass corrects only a part of the strabismus: the eyes will only be slightly straighter but will remain a bit crooked and the rest of the strabismus can be corrected surgically. Then there is the esotropia from an altered relationship between accommodative convergence and accommodation, wherein the eyes will be straight when the child looks away and will be diverted inward as he or she looks at something closely. In this case, the patient will use a pair of special glasses that are bifocal, where the lower part is the louder part of the lenses that will help avoid convergence when looking at something closely.