Authors
Kim, Sang-Yeob PhD; Cho, Hyun Gug PhD; Moon, Byeong-Yeon PhD; Yu, Dong-Sik PhD

Fusional Single Vision with Prism-induced Vergence Has More Influence than Diplopia on Postural Stability

publication date
October 21, 2019
Category
see more

Abstract/Introduction

SIGNIFICANCE 

Prism-induced convergence and vertical vergence for maintaining binocular fusion induced postural instability to a greater extent than diplopic conditions. This finding has important implication in relation to postural control of patients with large exophoria or vertical phoria in optometric clinic.

 

PURPOSE 

The purpose of this study was to examine whether binocular single vision with prism-induced horizontal and vertical vergence and diplopia might affect the static postural stability.

 

METHODS 

Forty-two subjects with a mean ± standard deviation age of 23.79 ± 2.81 years were enrolled in this study. To simulate convergence and divergence, base-in and base-out (BO) prisms of 4 and 8 Δ were added, respectively. To simulate vertical vergence, vertical prism of 2 Δ was added in a trial frame that corrected for the subject's refractive error during far distance (6 m) gaze. The prism power necessary to break fusion in each subject was detected and applied to induce diplopia in horizontal and vertical directions. Indices of general instability and sway power were measured under visual conditions using Tetrax and compared with normal viewing without the prism. Correlations between general instability indices and the ranges of break point in convergence and divergence were analyzed.


Conclusion/Results

RESULTS 

Postural instability was increased significantly when convergence induced by BO 4 and 8 Δ and vertical vergence induced by 2 Δ were stimulated. The correlation coefficient between ranges of BO break point and indices of general instability was −0.308 in the BO 4 Δ and −0.306 in the BO 8 Δ condition.

 

CONCLUSIONS 

Although binocular input is recognized as an important factor in postural stability, binocular input with excessively stimulated convergence and vertical vergence during a far distance gaze is a latent factor affecting postural stability. On the other hand, diplopia did not influence postural stability.


Testimonials


  • I haven't actually used the optometrist side, so my review is limited to the vision therapy offered.  This office was recommended by my occupational therapist for the treatment of my double vision following a stroke.


    Claire A.

  • Love this location. I had a brain injury accident from day one one. All the team make you feel you still important and hope in the horizon after when the medical system fell you miserably. Dr. Ikeda very professional and very understanding about your issue. Two tombs up.


    Jim K.

  • My husband and I were immediately impressed with Dr Ikeda. I was hit by a car while cycling which caused broken bones and three brain injuries. The brain injuries caused double vision. Dr. Ikeda examined my eyes and got me started on vision therapy with his occupational therapist who specializes in vision therapy.  She (Chris) is absolutely great.  I am impressed with the array of tools used to help recover my binocular vision.  I am doing things I never thought were possible (balance boards etc).  Chris pushes me and keeps me motivated. I really enjoy my sessions with her.  The office staff is always friendly and they have a wonderful appointment reminder tool that makes it easy to keep my calendar up to date. I am happy the rehab center at Little Co. of Mary recommended them!!


    Teresa S.

  • The Vision Therapy is handled in a separate office through a different door from the shared waiting room. Chris, the vision therapist, has a wide and varied assortment of tools, equipment and resources to best evaluate and treat most vision issues. After just a few visits, my double vision became easier to control, using exercises developed during the therapy process. It was time well-spent.


    Joe M.

  • I have been coming here since I can remember. I love it here. The staff is so amazing and nice. They explain everything they gonna do and never make you feel rushed. Dr. Ikeda has always been my doctor and I would never want another one. He is the doctor for my whole family and is always asking how everyone is doing. I am also so crazy about picking out my frames and have to try so many and each person who helps me take the time and lets me try them all on. I would never want to go anywhere else! I definitely would recommend this office to anyone looking for a great eye doctor.


    Kayla W.

Blog

Lighting-Assessment---Intensity-1

Lighting as Part of A Low Vision Evaluation

A low vision evaluation is in some ways similar to a regular eye exam, and in other ways entirely different. […]

Read More
josh-applegate-p_KJvKVsH14-unsplash

Can ADD/ADHD be a Vision Problem?

According to a study, approximately 20% of 4.5 million children currently identified as having ADHD may have been misdiagnosed. Furthermore […]

Read More
pexels-monstera-6186146

Are all magnifiers the same? The difference in optics between handheld magnifiers

Hand magnifiers are hand-held devices that can be placed over an object or text to enlarge or magnify what you […]

Read More
see all blogs

Contact Us To Amplify Your EyeCare

Working Hours

Monday - Thursday
8:00 am - 5:15pm
friday-sunday
Closed
Location
16816 Clark Ave, Bellflower, CA 90706, United States
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