Is foggy vision troubling you? Let our experienced optometrist restore your sight – book an appointment today and see the […]
Purpose.
To study the orbicularis oculi muscle response to asthenopia-inducing conditions.
Methods.
Twenty subjects (18–36 years) screened for 20/20 vision in each eye participated in the study. Subjects read passages under different asthenopia-inducing conditions. The inducing conditions were glare, low contrast, small font size, refractive error, up gaze, accommodative stress and convergence stress. Surface electromyography (EMG) was used to study the orbicularis oculi response from the right eye. Palpebral fissure height was measured from recorded video images of the right eye. At the end of each condition subjects were asked to rate the severity and type of visual discomfort experienced.
Results.
Outcome measures for the asthenopia-inducing conditions were compared with their respective nonstress controls. Repeated measures analysis of variance was used to analyze the data. Refractive error (p = 0.0001), glare (p = 0.0001), low contrast (p = 0.007), small font (p = 0.034), and up gaze (p = 0.001) resulted in a significant increase in EMG power. Refractive error (p = 0.0001) and glare (p = 0.0001) also caused significant reduction in aperture size. Reading a low contrast text caused a reduction in blink rate (p = 0.035), whereas refractive error (p = 0.005) and glare (p = 0.01) caused an increase in blink rate. All conditions induced significant visual discomfort (p < 0.001).
Conclusion.
Refractive error and glare, which reduce image quality and benefit from eyelid squint, caused increased EMG power, eyelid squint response and increased blink rate. Low contrast and small font, which reduce image quality but do not benefit from eyelid squint, resulted in increased EMG power without changes in aperture size and reduced blink rate (for low contrast). Accommodative and convergence stress (in subjects with normal accommodative and vergence abilities) did not cause changes in EMG power, aperture size or blink rate. These results suggest that contraction of the orbicularis oculi is a part of the asthenopia mechanism related to compromised image quality.
Vision therapy is well worth the response, time and effort. Our Son had a hard time focusing and writing neatly. After vision therapy Seth could complete a task in half the time if previously took. His abilities to focus improved greatly and so did his handwriting.
Also, he was better at listening. As a parent, we wanted learning to be fun for our Son, and vision therapy made this possible.
Vision Therapy is well worth the expense, time and effort. Our son had a hard time focusing handwriting neatly. After vision therapy Seth could complete a task in half the time it previously took his abilities to focus and improved greatly and so did his handwriting.
Also, he was better at listening. As a parent you wanted learning to be fun for our son and vision therapy made this possible.
Vision Therapy has given or son the tools he needs to be able to scan and read the written word more effectively and efficiently.
He love working with John and these working sessions give him the motivation to gladly work on his homework assignments.
It amazed us to see the difference in the tracking of his eyes and along a line of it's from the beginning to the end of the treatment.
Dr. McBryar , Kristen and John are all marvelous and we would recommend them to anyone I only wish that we would have found them sooner!
Prior to coming to the institute for vision development my son complained of daily headaches. Therapy has eliminated his headaches completely. I love knowing my son is able to learn pain-free for the rest of his life because of the work that has been done over just a few weeks in this office. He he absolutely loved coming that didn't even feel like going to a doctor or therapy. We are grateful for the relief he was able to find by coming here.
Thank you!
Seems much less frustrated with life
Reads non-stop and fast
Spelling abilities have been hugely improved
Seems much more confident
Thank You!!!
When we first came to the practice, my son did not have huge issues, but lots of small ones- trouble with reading, sports (hitting the baseball consistently), coordination, etc- that were not easily detectable,but when put together presented issues. The staff here were all very professional and loving towards him. While I was concerned in the reading, my son was concerned with the athletic side. Seeing improvement night off the bat gave him confidence that i have nor seen in him and made him want to not only Come to therapy, but also made him want to work hard. He has surpassed his grade level and above in reading and hit his first home run this year! Thank you!!!
Is foggy vision troubling you? Let our experienced optometrist restore your sight – book an appointment today and see the […]
According to the National Eye Institute, nystagmus affects approximately 0.24% of the general population in the United States. This means […]
Are you tired of dealing with eyelid inflammation? Well, there's good news for you! Hypochlorous acid, a natural bactericidal compound, […]
