Vision: Cases and Questions

Contents

By Minna Saslaw, MD.

Learning Objectives:

  1. Know the AAP recommendations for eye evaluation and vision screening, and when to refer.
  2. Understand development of normal eye movements and visual acuity.
  3. Know the different physical examination techniques used in vision screening and the conditions they detect. Practice the cover/uncover tests. Know the treatment options for Strabismus and Amblyopia.
  4. Know special circumstances that require screening and/or regular follow-up by an ophthalmologist.


General:

Eye evaluation should start at the initial newborn visit and occur at every well child visit. This evaluation includes an ocular history, vision assessment, external exam, assessment of ocular motility, examination of the pupil and a red reflex examination. Visual acuity testing and attempt at ophthalmoscopy is recommended in children 3yo and older.


Definitions:

Strabismus – ocular misalignment. It is divided into "phorias" and "tropias" and the direction of the misalignment (exo-lateral deviation, eso-medial deviation, hypo-downward, hyper-upward). A "tropia" is an apparent misalignment that is readily visible. The affected eye always points in one direction. A "phoria" is a latent tendency to deviate. Sometimes this may be intermittent due to fatigue, illness or stress and may only be apparent at home or seen with the cover-uncover test.

Amblyopia - the loss of vision due to absence of stimulation of the retina secondary to opacities affecting the visual axis, strabismus or refractive error. Amblyopia can occur with or without strabismus.

Leukocoria – a white pupillary reflex

 

Case 1:  At a 4 year WCC visit the visual acuity testing shows 20/30 vision in both eyes, do you refer to ophthalmology? Would you refer if the R eye was 20/20 and L eye 20/40?

Case 2:  During a 1mo weight check visit a parent is concerned because the eyes sometimes appear cross-eyed what do you say? What would you say at the 6mo visit? The same parent asks when can the baby see and if he can see colors?

Case 3:  You are seeing a 2 month old for a well child visit. The father shows you the family holiday picture and you notice that only the right eye has red eye in the picture and the left eye looks white. Are you concerned? An 18mo seems to be cross-eyed, how do you evaluate this?

Case 4:  A post-doctoral fellow brings his 2month old for a well child visit and asks what developmental milestones should he look out for in order to know his daughter’s vision is developing correctly?

Case 5:  What other conditions or family history that may affect visual development should prompt an ophthalmology referral?


References:

  1. American Academy of Pediatrics, Committee on Practice and Ambulatory Medicine and Section on Ophthalmology et. Al. Policy Statement: Eye Examination in Infants, Children and Young Adults by Pediatricians. Pediatrics. April 2003; 111; 902-7. Statement reaffirmed in 2007.
  2. American Academy of Pediatrics, Section on Ophthalmology. Policy Statement: Red Reflex Examination in Infants. Pediatrics. May 2002; 109; 980-1.
  3. Broderick, Peter, M.D. Pediatric Vision Screening for the Family Physician. American Family Physician. Sept 1, 1998;58; 691-700. (All of the diagrams except for the Snellen and HOTV charts are from here).
  4. American Academy of Pediatrics, Surgical Advisory Panel. Guidelines for Referral to Pediatric Surgical Specialists. Pediatrics. July 2002;110; 187-191
  5. http://www.psych.ucalgary.ca/PACE/VA-Lab/Marcela/Pages/index.html (VISUAL DEVELOPMENT)
  6. Silbernagl, Stefan, et. Al. Color Atlas of Pathophysiology. 2000. 324. (COLOR VISION)
  7. "Red-Green Color Vision Defects". http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=gene&part=rgcb
  8. http://www.health.state.mn.us/divs/fh/mch/webcourse/vision/toc.cfm (GOOD TUTORIAL ON VISION SCREENING)
  9. Merck Manual. Sections on Strabismus and Amblyopia. 2007.
  10. US Preventive Services Task Force. Vision screening for children 1 to 5 years of age: US Preventive Services Task Force recommendation statement. Pediatrics. 2011;127(2):340–346
  11. Another good vision screening tutorial with cases, (Good cases with questions)
    http://one.aao.org/Flash/VisionScreening/PediatricVisionScreening.html
  12. Instrument-Based Pediatric Vision Screening Policy Statement. Pediatrics. 2012;130(5):983-986.