Authors
Asper, Lisa; Leung, Andrew; Tran, Catrin; Suttle, Catherine M.; Watt, Kathleen

The Effects of Vertical Yoked Prism on Horizontal Heterophoria

publication date
Category
see more

Abstract/Introduction

Purpose 

Vertical yoked prisms (VYPs) have been recommended for the remediation of vergence dysfunction, but the evidence base for their use is mostly low level. This study investigates the effect of VYP on horizontal subjective dissociated heterophoria.

 

Methods 

Phoria measurement was performed in primary gaze with the Modified Thorington technique at 3 m and at 40 cm on 40 nonpresbyopic young adults. Subjects were seated and head position was held constant. Baseline measures (without yoked prism) of distance and near phoria were measured. Phorias were measured again through the following range of VYP, randomly presented: 2 prism diopters (Δ) base up (BU), 2Δ base down (BD), 5Δ BU, and 5Δ BD. Twenty-six subjects also had their phorias measured with control lenses of +0.125 DS OU (because of unavailability of Plano trial lenses) randomly presented along the other conditions.


Conclusion/Results

Results 

There was no significant difference overall between phoria measured in any of the yoked prism conditions, including the baseline measure, at distance or near. Neither was there evidence of a predictable esophoric or exophoric shift with either BU or BD prism.

 

Conclusions 

Vertical yoked prisms did not exert any immediate effect on horizontal phoria in young adults when posture was controlled. This suggests that, if VYPs do indeed improve horizontal vergence problems, they do not do so by a direct or immediate impact on horizontal phoria.


Testimonials


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.


Amanda T.

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.


Alexa H.

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!


Charlotte M.

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!


Olivia C.

Seems much less frustrated with life

Reads non-stop and fast

Spelling abilities have been hugely improved

Seems much more confident

Thank You!!!


Kelly O.

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!!!


Alice M.
1 2 3 10

Blog

frustrated-millennial-businessman-having-strong-headache-tired-from-laptop-work

The impact of screen time on dry eye: tips for prevention

According to a recent study, people who spend more than 2 hours a day on digital devices are 2.5 times […]

Read More
pexels-katerina-holmes-5905492

Chattanooga pediatric eye doctor shares how children with vision problems can struggle academically

Many people believe that good eyesight is simply the ability to read the "20/20" line on an eye chart, but […]

Read More
medicine-health-care-eyesight-concept-unrecognizable-female-shows-her-inflated-red-eye-with-blood-capillary

Is there a difference between a scratched eye and a scratched cornea?

Corneal abrasions, or scratched corneas, are a common occurrence and make up a significant portion of eye injury cases. In […]

Read More
see all blogs

Contact Us To Amplify Your EyeCare

Working Hours

Monday - Thursday
8:00 am - 5:15pm
friday-sunday
Closed
Location
1043 Executive Drive Suite #101 Hixson, TN 37343
Website Accessibility Policy
Safety protocols page
phone-handsetarrow-uparrow-right linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram