OPTOMETRIC CLINICAL PRACTICE GUIDELINE OPTOMETRY: THE PRIMARY EYE CARE PROFESSION Doctors of optometry are independent primary health care providers who examine, diagnose, treat, and manage diseases and disorders of the visual system, the eye, and associated structures as well as diagnose related systemic conditions. Optometrists provide more than two-thirds of the primary eye care services in the United States. They are more widely distributed geographically than other eye care providers and are readily accessible for the delivery of eye and vision care services. There are approximately 36,000 full-time equivalent doctors of optometry currently in practice in the United States. Optometrists practice in more than 6,500 communities Care of the Patient with across the United States, serving as the sole primary eye care providers in more than 3,500 communities. Strabismus: The mission of the profession of optometry is to fulfill the vision and eye care needs of the public through clinical care, research, and education, all Esotropia and of which enhance the quality of life. Exotropia OPTOMETRIC CLINICAL PRACTICE GUIDELINE CARE OF THE PATIENT WITH STRABISMUS: ESOTROPIA AND EXOTROPIA Reference Guide for Clinicians Prepared by the American Optometric Association Consensus Panel on Care of the Patient with Strabismus: Robert P. Rutstein, O.D., Principal Author Martin S. Cogen, M.D. Susan A. Cotter, O.D. Kent M. Daum, O.D., Ph.D. Rochelle L. Mozlin, O.D. Julie M. Ryan, O.D. Edited by: Robert P. Rutstein, O.D., M.S. Reviewed by the AOA Clinical Guidelines Coordinating Committee: David A. Heath, O.D., Ed.M., Chair NOTE: Clinicians should not rely on the Clinical Diane T. Adamczyk, O.D. Guideline alone for patient care and management. John F. Amos, O.D., M.S. Refer to the listed references and other sources Brian E. Mathie, O.D. for a more detailed analysis and discussion of Stephen C. Miller, O.D. research and patient care information. The information in the Guideline is current as of the date of publication. It will be reviewed periodically Approved by the AOA Board of Trustees, June 28, 1995 and revised as needed. Revised 1999; reviewed 2004; revised 2010 © American Optometric Association, 2011 243 N. Lindbergh Blvd., St. Louis, MO 63141-7881 Printed in U.S.A. Strabismus: Esotropia and Exotropia iii iv Strabismus: Esotropia and Exotropia TABLE OF CONTENTS b. Signs, Symptoms, and Complications ............. 21 c. Early Detection and Prevention ....................... 21 INTRODUCTION ................................................................................... 1 6. Intermittent Exotropia ................................................ 21 a. Natural History ................................................ 21 I. STATEMENT OF THE PROBLEM ........................................... 2 b. Signs, Symptoms, and Complications ............. 21 A. Description and Classification of Strabismus ........................ 4 c. Early Detection and Prevention ....................... 22 1. Esotropia ...................................................................... 5 7. Mechanical Esotropia and Exotropia ......................... 22 a. Infantile Esotropia .............................................. 5 a. Natural History ................................................ 22 b. Acquired Esotropia ............................................ 5 b. Signs, Symptoms, and Complications ............. 23 c. Secondary Esotropia .......................................... 7 c. Early Detection and Prevention ....................... 23 d. Microesotropia ................................................... 8 8. Microtropia ................................................................ 23 2. Exotropia ..................................................................... 8 a. Natural History ................................................ 23 a. Infantile Exotropia ............................................. 9 b. Signs, Symptoms, and Complications ............. 23 b. Acquired Exotropia ............................................ 9 c. Early Detection and Prevention ....................... 24 c. Secondary Exotropia ........................................ 10 9. Sensory Esotropia ...................................................... 24 d. Microexotropia ................................................. 11 a. Natural History ................................................ 24 B. Epidemiology of Strabismus ............................................... 11 b. Signs, Symptoms, and Complications ............. 24 1. Incidence and Prevalence .......................................... 11 c. Early Detection and Prevention ....................... 24 2. Risk Factors ............................................................... 12 10. Sensory Exotropia ...................................................... 25 C. Clinical Background of Strabismus ..................................... 12 a. Natural History ................................................ 25 1. Accommodative Esotropia......................................... 12 b. Signs, Symptoms, and Complications ............. 25 a. Natural History ................................................ 12 c. Early Detection and Prevention ....................... 25 b. Signs, Symptoms, and Complications ............. 13 c. Early Detection and Prevention ....................... 14 II. CARE PROCESS ........................................................................ 26 2. Acute Esotropia and Exotropia .................................. 14 A. Diagnosis of Strabismus ...................................................... 26 a. Natural History ................................................ 14 1. Patient History ........................................................... 26 b. Signs, Symptoms, and Complications ............. 15 2. Ocular Examination ................................................... 27 c. Early Detection and Prevention ....................... 15 a. Visual Acuity .................................................. 27 3. Consecutive Esotropia and Exotropia ........................ 15 b. Ocular Motor Deviation ................................... 28 a. Natural History ................................................ 15 c. Monocular Fixation .......................................... 28 b. Signs, Symptoms, and Complications ............. 16 d. Extraocular Muscle Function ........................... 28 c. Early Detection and Prevention ....................... 16 e. Sensorimotor Fusion ........................................ 29 4. Infantile Esotropia ..................................................... 19 f. Accommodation ............................................... 29 a. Natural History ................................................ 19 g. Refraction......................................................... 30 b. Signs, Symptoms, and Complications ............. 19 h. Ocular Health Assessment and Systemic c. Early Detection and Prevention ....................... 19 Health Screening .............................................. 30 5. Infantile Exotropia ..................................................... 20 B. Management of Strabismus ................................................. 30 a. Natural History ................................................ 20 1. Basis for Treatment ................................................... 31 Strabismus: Esotropia and Exotropia v vi Strabismus: Esotropia and Exotropia 2. Available Treatment Options ..................................... 31 a. Optical Correction ............................................ 31 b. Added Lens Power ........................................... 32 c. Prisms .............................................................. 33 d. Vision Therapy ................................................ 34 e. Pharmacological Agents .................................. 35 f. Extraocular Muscle Surgery ............................ 36 g. Chemodenervation ........................................... 38 3. Management Strategies for Strabismus ..................... 38 a. Accommodative Esotropia ............................... 38 b. Acute Esotropia and Exotropia ........................ 40 c. Consecutive Esotropia and Exotropia .............. 40 d. Infantile Esotropia and Exotropia .................... 41 e. Intermittent Exotropia ...................................... 42 f. Mechanical Esotropia and Exotropia ............... 44 g. Microtropia ...................................................... 44 h. Sensory Esotropia and Exotropia ..................... 45 4. Patient Education ....................................................... 45 5. Prognosis and Follow-up ........................................... 46 CONCLUSION ..................................................................................... 47 III. REFERENCES ......................................................................... 48 IV. APPENDIX ............................................................................... 66 Figure 1: Optometric Management of the Patient with Strabismus: A Brief Flowchart ............................ 66 Figure 2: Frequency and Composition of Evaluation and Management Visits for Esotropia and Exotropia ... 67 Figure 3: ICD-10-CM Classification of Esotropia and Exotropia ............................................................. 69 Abbreviations of Commonly Used Terms ................................. 71 Glossary ..................................................................................... 72 Introduction 1 2 Strabismus: Esotropia and Exotropia INTRODUCTION