What Is Strabismus & How It Affects Eyewear Measurements?12/08/2021
Strabismus has to do with visual alignment which plays a vital role in how a person can see. Various problems of the eyes such as nystagmus, crossed eyes, amblyopia, or better known as lazy eye…they are all forms of strabismus. Many of these are easy for an Optician to spot prior to getting eyewear measurements.
Right now, let’s define strabismus in very basic terms.
Strabismus occurs when one or more of the muscles of the eye don’t function as they should leading to misalignment or eyes that don’t move as they should. This could cause double vision(diplopia) and more. Sometimes people are born with strabismus and other acquire strabismus through injury, however, it can be treated in a variety of ways by an Ophthalmologist.
One of the more common types of strabismus is lazy eye, or amblyopia. The more proper term for it is strabismic amblyopia. Just above, it is stated that some babies are born with this condition. Being born with any condition is termed congenital.
As the child ages, it may become more noticeable as newborns generally have weakened extraocular muscles, thus harder to see. As they get older though, even before their first birthday, the muscles should work together fine, however, for some, they don’t, thus, the diagnosis. Ophthalmologists, again, have several treatments, and for this type of amblyopia, early treatment is key to gaining “control” of the lazy eye. For example, some children wear a patch over the more dominant eye in order to strengthen the weak eye. It forces the child to use it.
There are many more examples of strabismus, but for now, it is generally abnormal muscle function of the extraocular muscles that cause strabismus. It does have many treatments while being overall painless, however, causing much difficulty with vision.
As far as the Optician, he or she doesn’t diagnose, but must measure properly for eyewear when it comes to patients with strabismus. The optical centers must be measured properly on the eyewear. It’s possible that the laboratory will confirm the OC to be certain the measurement isn’t erroneous because most of the time, OC’s are within one to two millimeters of each other. When a patient has strabismus, the OC’s of each individual eye could differ by more than 5 millimeters.