What is pseudostrabismus?
Pseudostrabismus is a condition where a child’s eyes appear to be misaligned but are not. Children who have pseudostrabismus usually have nose bridges that are flat and inner eyelid folds that are larger than normal. This creates less white space between the colored iris and the inner eyelid, and this results in the appearance of the eyes looking in different directions, being crossed, or being misaligned, despite them being correctly aligned.
There are four main types of pseudostrabismus:
- Positive Angle Kappa: This type of pseudostrabismus occurs when reflected light is not centered on the pupil even as the pupil looks directly at the light source. This makes the eye appear as though is it turning outward.
- Pseudoesotropia: The most common form of pseudostrabismus. Typically, the eyes appear crossed.
- Pseudoexotropia: The eyes appear to be turned outward.
- Pseudohypertropia: There is an illusion that the eyes are vertically misaligned, meaning that one eye appears higher than the second eye.
Psuedostrabismus Risk Factors
A handful of risk factors may lead to pseudostrabismus. These include:
- Premature birth: Children who are born prematurely may have folds in their macula, a part of the eye that processes what is seen. This is referred to as macular dragging. This can result in pseudohypertropia.
- Facial structure: Asian children are at a higher risk of developing pseudoesotropia due to the upper eyelid folds above their eye.
- Orbital tumors: Orbital tumors (abnormal tissue growth around the eye) may result in pseudohypertropia.
- Orbital trauma: In some cases, eye displacement resulting from an injury to the skull can cause pseudohypertropia.
- Eyelid retraction: A retraction in the eyelid can cause psuedohypertropia.
- Toxocariasis: A parasitic infection caused by roundworms, this disease can lead to pseudohypertropia.
- Chorioretinal infections: These types of infections may result in the scarring of the choroid and in retina and macular dragging. This can lead to pseudoexotropia.
Pseudostrabismus vs. Strabismus
In cases of pseudostrabismus, the eyes only appear to be misaligned. In contrast, strabismus occurs when the eyes are looking in different directions or are misaligned. Misalignment of the eyes may cause one eye to stray inward while the other eye remains straight or focused. Other symptoms included uncoordinated eye movements and vision in only one eye.
Strabismus will occasionally affect newborns, but most outgrow it. That being said, a failure to address this condition early could result in permanent vision loss. Treatment for strabismus includes eye patches, glasses, or even surgery.
Pseudostrabismus, on the other hand, is harmless and does not lead to any vision loss. In fact, as a child grows with pseudostrabismus, the condition often goes away as their features, particularly the nose and eyes, change.
Diagnosing Pseudostrabismus vs. Strabismus
A quick method of differentiating between pseudostrabismus and strabismus is by capturing a flash photo of your child and examining the photo carefully. Ensure that the child's face and eyes are aimed directly at the camera. Observe where the light is reflecting in your child’s eyes. If your child has psuedostrabismus, then the light should be reflected at the same place in both eyes. On the other hand, in cases of strabismus, the light will be reflected in different areas of each eye.
However, this method is not perfect, and a self-diagnosis for this condition should be taken with a grain of salt. It’s also important to note that a child’s eyes may become misaligned for a short period of time before returning to a correct alignment without intervention.
Since accurately diagnosing this condition can be difficult, an eye exam conducted by an eye doctor is recommended. Since strabismus may result in permanent vision loss, it’s important to make a proper diagnosis as soon as possible.
During the evaluation process, the eye doctor will perform a thorough examination, asking questions about the patient’s medical history, when the symptoms began, and how long they have been occurring. A total eye exam will also be needed and will consist of the following tests:
- A test to evaluate how light reflects off the cornea
- A cover-uncover test
- An eyedrop test
- An external eye structure examination
These tests can help determine whether your child has pseudostrabismus or strabismus. In addition, an eye exam can also pick up on other conditions that children with strabismus often have, such as amblyopia, also known as lazy eye, or refractive errors such as farsightedness.
It's important to have your child’s eyes examined as soon as possible to rule out strabismus. Strabismus can affect your child’s vision, and the sooner your child receives treatment, the better their chances of developing normal vision become.
Pseudostrabismus does not require any treatment and usually clears up on its own. This is because this condition usually reveals itself in infancy, and as your child grows, their facial features change. In the end, this improves the appearance of misalignment.
The general outlook for pseudostrabismus is good. Most cases resolve on their own as a child reaches the age of 2 or 3 years old.
There are also some cases that persist into adulthood, though. For instance, those of Asian ethnicity may retain a broad nasal bridge into adulthood and could thus also carry pseudostrabismus into adulthood.
Since pseudostrabismus could cover up an authentic case of strabismus later in life, it’s important to have annual eye exams if you or your child has either condition.