Posted on June 12, 2017
Neuro-Ophthalmology Perspective of Strabismus
Guest post from our Neuro-Ophthalmology partner Dr. Krista Kinard, MD.
We are so blessed here at the Spokane Eye Clinic to have the support of many ophthalmology sub-specialists that are willing to help us as needed with kids. Without them we might have to send more patients to Seattle or Portland for some specialized services. One example is Dr. Krista Kinard, our Neuro-Ophthalmologist, who specializes in the connections between the eyes and the brain. She is the only Neuro-Ophthalmologist in the Inland Northwest region. She has been kind enough to share with us her perspective on strabismus...
"Double vision (diplopia) is when a person see's two of the same object instead of one. Diplopia can be monocular or binocular. Binocular diplopia occurs when an image falls on non-corresponding parts of the two retinas because of ocular misalignment. Binocular diplopia is typically not caused by a problem with the eye. The double vision is binocular if it completely resolves with closing either eye. Monocular double vision persists if one eye is closed and can be in one or both eyes. Monocular diplopia is typically due to an eye problem and is not caused by a neurological problem. Monocular diplopia is typically seen as a “ghost image” or an overlap of images.
Strabismus is the term used when the two eyes are misaligned. Strabismus can be congenital or acquired. Acquired strabismus is typically caused by a neurologic or muscular abnormality whereas congenital strabismus is something people are born with or starts at an early age. Congenital strabismus is typically comitant, meaning that the misalignment between the eyes is the same in all directions of eye movement and the eyes are able to move fully in all directions. Acquired strabismus is typically noncomitant, meaning that the misalignment is different in certain directions of eye movements and/or eye movements are not full/complete in both eyes.
People can be born with their eyes perfectly straight or misaligned. If misalignment of the eyes is present in a child (typically under the age of 7 but up to the age of 12), they will not see double like an adult will because their visual system has not yet developed. Many people are also born with their eyes appearing straight but when vision is relaxed, there is a tendency for the eyes to drift out of alignment. In these people, the majority of the time the brain and eyes work together to keep the eyes straight and to keep an image single. Over time or with injury or illness, this ability to keep the eyes straight can break down and double vision can develop. This is called decompensated congenital strabismus. Strabismus in children should be treated to help prevent “lazy eye” known as amblyopia. Strabismus in adults can be fixed with prism or surgically. Eye contact is one of a human’s major methods of communication, so aligning the eyes can greatly improve not only vision and depth perception but also a person’s ability to communicate, all of which are important for normal function and improved quality of life."