Study of the Effect of Accommodative Insufficiency

109 Pages·2012·4.46 MB·English

Study of the Effect of Accommodative Insufficiency
(SEA IT)

THESIS

Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in
the Graduate School of The Ohio State University

By
Nahrain M. Shasteen, OD
Graduate Program in Vision Science

The Ohio State University
2012

Master's Examination Committee:
Marjean Taylor Kulp, OD, MS, Advisor
Michael J. Earley, OD, PhD
G. Lynn Mitchell, MAS
Donald O. Mutti, OD, PhD
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Copyright by
Nahrain M. Shasteen, OD
2012

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Abstract

Accommodative insufficiency is a binocular vision disorder characterized by a
decrease in age expected amplitudes of accommodation. This condition can result in
symptoms of headaches, blurred vision and asthenopia. Vision therapy has been utilized
in helping treat patients with accommodative insufficiency. The purpose of this study was
to evaluate the repeatability of the Convergence Insufficiency Symptom Survey (CISS) in
subjects with accommodative insufficiency. This study also examined the improvement
in CISS scores following 8 weeks of weekly 1-hour office-based vision therapy with
home reinforcement. Improvements in accommodation and vergence measures were also
examined as part of this study. Subjects ages 9 to 30 were enrolled in the study. Measures
of amplitudes of accommodation, accommodative facility, accommodative response, and
vergence function were evaluated at baseline and were repeated following 8 weeks of
vision therapy. Final outcome sensorimotor measures and CISS scores were collected by
examiners masked to the subject’s progress and compliance with vision therapy. Using
the method described by Bland-Altman, the CISS was found to be repeatable in subjects
with accommodative insufficiency. The mean difference in scores between two
administrations was 1.47 point with 95% limits of agreement of -5.19 and 8.13. Analysis
using student’s t or the Wilcoxan sign rank test showed a statistically significant
improvement in amplitudes of accommodation (AA) (p<0.001), monocular
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accommodative facility (MAF) (p0.0009) and amplitude scaled monocular
accommodative facility (MAF-S) (p0.034). Statistically significant improvements in
CISS scores were also noted (p=0.0003). Accommodative function is known to decrease
with increasing age. Therefore, differences in improvements between adults and children
were also investigated. The Kruskal-Wallis test showed statistically significant
differences in improvements between age groups in AA, MAF, and CISS. The results of
this study show that 8 weeks of weekly 1-hour office-based vision therapy and home
reinforcement results in a decrease of symptoms and increase in accommodative
measures in patients with accommodative insufficiency.

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Dedication

This document is dedicated to:
My grandparents
Avshalim & Pabronia Daniel and Franklin & Sadonna Shasteen;
who always believed in the great things I would accomplish,
but were unable to see them come to fruition on this earth.

And to my parents, Philip and Roza Shasteen, and my sister, Yasmine,
for their strength, encouragement, faith, and prayers throughout my life.

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Acknowledgments
I wish to thank my advisor, Dr. Marjean Taylor Kulp, for encouraging me to pursue the
advanced practice fellowship when I was completing my optometric education. Thank
you for your unyielding commitment to this project, sharing your expertise, and for your
constant encouragement, assistance, and patience throughout this process.

To my remaining committee members:

o Dr. Michael Earley, who has been a steadfast mentor since my first days in
optometry school. Thank you for always challenging me clinically and
professionally.

o Professor Lynn Mitchell, thank you for your support and immense help in
navigating the statistical waters for this project.

o Dr. Donald Mutti, for sharing your vast knowledge, guidance, and assistance in
the wide world of accommodation. Thank you also for your always ready
“emergency tech support.”

I would also like to thank:

Dr. Kathryn Richdale for sharing this idea and research opportunity with me.

Dr. Marjean Taylor Kulp, Dr. Andrew Toole, and Dr. Aaron Zimmerman for serving as
masked examiners.

Dr. Melissa Bailey for use of the Visante OCT and in helping whenever I was in need.

Mr. Kevin Guckes, Dr. Andrew Toole, Dr. Marjean Taylor Kulp, and the host of student
workers who lent a hand in keeping an eye on “Fred” the PowerRefractor.

Ms. Kerri Mctigue, for your work in designing the beautiful recruitment brochures.

To ALL my family, friends, instructors and colleagues; thank you for your prayers and
support throughout this entire process.

I could have never made it without you!

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Vita
2001................................................................Defiance Senior High School, Defiance, OH
2008................................................................B.S. Vision Science, The Ohio State
University
2009................................................................O.D. The Ohio State University
2010-Present .................................................Advanced Practice Fellowship, Binocular
Vision and Pediatrics, The Ohio State
University
2010-2011 ......................................................Graduate Teaching Associate, Optometry,
The Ohio State University
2011-Present ..................................................Auxiliary Faculty, Optometry, The Ohio
State University

Publications

Shasteen NM, Nguyen L, Kulp MT. 2011. Comparison of visual acuity testing at 5 versus
10 feet in school-aged children [Abstract]. Optom Vis Sci 2011:88:E-abstract 115788.

Fields of Study

Major Field: Vision Science

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Table of Contents

Abstract .............................................................................................................................. ii
Dedication ......................................................................................................................... iv
Acknowledgments ............................................................................................................. v
Vita .................................................................................................................................... vi
List of Tables ..................................................................................................................... x
List of Figures ................................................................................................................... xi
CHAPTER 1: INTRODUCTION .................................................................................... 1
Definition and Identification of Accommodative Insufficiency ............................. 1
Public Health Significance ...................................................................................... 4
Ocular Accommodation .......................................................................................... 5
Relationship between Accommodation and Vergence ........................................... 9
Treatments............................................................................................................. 11
Symptoms Associated with Accommodative Dysfunction................................... 23
Study Purpose ....................................................................................................... 24
CHAPTER 2: METHODS ............................................................................................. 26
Subjects ................................................................................................................. 26
Eligibility Requirements ....................................................................................... 26
Baseline Examination ........................................................................................... 28
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Sensorimotor Examination.................................................................................... 29
AC/A Ratio and Accommodative Response ......................................................... 31
Symptom and Academic Behavior Surveys ......................................................... 33
In-Office Therapy Sessions................................................................................... 34
In Office Therapy Procedures ............................................................................... 35
Home Therapy Procedures .................................................................................... 45
Final Outcome Examination ................................................................................. 49
Data Analysis ........................................................................................................ 49
CHAPTER 3: RESULTS ............................................................................................... 51
Enrollment and Completion of Study Visits ......................................................... 51
Demographics and Refractive Status .................................................................... 51
Baseline Measures ................................................................................................ 52
CISS Repeatability ................................................................................................ 57
Final Outcome Measures ...................................................................................... 58
Sensorimotor Examination Measures ................................................................... 58
Improvements of Clinical Measures and Symptoms ............................................ 62
Effects of Age on Improvement ............................................................................ 67
Correlation Between Signs and Symptoms........................................................... 71
Compliance ........................................................................................................... 72
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CHAPTER 4: DISCUSSION ......................................................................................... 73
Study Strengths ..................................................................................................... 79
Study Limitations .................................................................................................. 79
Future Study Considerations ................................................................................. 80
CHAPTER 5: CONCLUSION....................................................................................... 82
Appendix A ...................................................................................................................... 83
Appendix B ...................................................................................................................... 85
Appendix C ...................................................................................................................... 87
Appendix D ...................................................................................................................... 89
REFERENCES ................................................................................................................ 91

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