Authors
Ravikumar, Ayeswarya; Marsack, Jason D.; Benoit, Julia S.; Anderson, Heather A.

Simulated Keratometry Repeatability in Subjects with and without Down Syndrome

publication date
see more

Abstract/Introduction

Purpose 

To assess the repeatability of simulated keratometry measures obtained with Zeiss Atlas topography for subjects with and without Down syndrome (DS).

Methods 

Corneal topography was attempted on 140 subjects with DS and 138 controls (aged 7–59 years). Subjects who had at least three measures in each eye were included in analysis (DS: n = 140 eyes (70 subjects) and controls: n = 264 eyes (132 subjects)). For each measurement, the steep corneal power (K), corneal astigmatism, flat K orientation, power vector representation of astigmatism (J0, J45), and astigmatic dioptric difference were determined for each measurement (collectively termed keratometry values here). For flat K orientation comparisons, only eyes with >0.50 DC of astigmatism were included (DS: n = 131 eyes (68 subjects) and control: n = 217 eyes (119 subjects)). Repeatability was assessed using (1) group mean variability (average standard deviation (SD) across subjects), (2) coefficient of repeatability (COR), (3) coefficient of variation (COV), and (4) intraclass correlation coefficient (ICC).


Conclusion/Results

Results 

The keratometry values showed good repeatability as evidenced by low group mean variability for DS versus control eyes (≤0.26D vs. ≤0.09D for all dioptric values; 4.51° vs. 3.16° for flat K orientation); however, the group mean variability was significantly higher in DS eyes than control eyes for all parameters (p ≤ 0.03). On average, group mean variability was 2.5 times greater in the DS eyes compared to control eyes across the keratometry values. Other metrics of repeatability also indicated good repeatability for both populations for each keratometry value, although repeatability was always better in the control eyes.

Conclusions 

DS eyes showed more variability (on average: 2.5×) compared to controls for all keratometry values. Although differences were statistically significant, on average 91% of DS eyes had variability ≤0.50D for steep K and astigmatism, and 75% of DS eyes had variability ≤5 degrees for flat K orientation.


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.

Blog

group-of-small-nursery-school-children-with-teache-W2UF5RU

Vision Among Us

One of the challenges with visual impairments and visual deficits is that it's difficult to detect them just by looking […]

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

Vision Therapy for Neurological Conditions

Each year an estimated 1.5 million Americans sustain a traumatic brain injury (TBI). According to the Neuro Optometric Rehabilitation Association, […]

Read More
DSC_2077

Vision Therapy for Adults

Adults generally accept changes in themselves as part of aging, and think that there's nothing they can do about it. […]

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