Low Vision Rehabilitation/Zach Davis

Zach on his mountain bike

Nystagmus

You are very interested in your new patient, Zach Davis as he is the first patient you have seen with nystagmus. Zach will help you to refresh your understanding of nystagmus and through him you will learn the appropriate management strategies for patients with this condition.
There is an overarching question you will need to answer, and scenarios with supporting information to help guide your understanding and formulate your answer.

Question

How do I identify and evaluate a patient with nystagmus and select the appropriate management strategy?
Use the scenario and resources below to formulate your own response to this question. You will need to be able to discuss the principles of null point training and formulate a program to train a patient in the use of null point strategy.

Activities

Zach is 14 years old and attends See Well Australia with his mother. He was diagnosed with congenital nystagmus at the age of 5. His mum says he has had “dancing eyes” since birth. Zach attends main-stream school, in year 8 and is mostly keeping up with his schoolwork. Has a visiting teacher once a month now. Zach and his mum want more information about whether his vision can be improved as he is a keen bike rider and his mum is particularly worried about him when he is mountain-biking as he is starting to compete at state level.
POH:Glasses only. Ophthalmic diagnosis = Congenital motor nystagmus with decreased visual acuity.
Vert: R) +0.75DS L) +1.00/-0.50x 75
FH:Younger sister has congenital ET.
GH:Generally good, mild asthma. Rx ventolin PRN.

Your examination reveals the following information:

VA cc: R) 6/24 L) 6/36 (BEO cc/sc: 6/24, N10-12)
Contrast:1.05 log (moderately reduced contrast)

You notice moderate amplitude pendular nystagmus in the primary position. This becomes a right-beating nystagmus on right gaze and a leftbeating nystagmus on left gaze. There is no change to the amplitude when either eye is occluded.

Task 1
Refresh your understanding of nystagmus by watching the nystagmus playlist and answer the following questions:

1. What type of nystagmus do parents most often notice in their children?
   
2. List 3 things that could increase the amplitude of nystagmus?
   
3. Describe at least 3 symptoms of nystagmus.
   
4. Examination of a patient with nystagmus involves which tests?
   

Task 2

Read these two electronic resources about nystagmus which explain the low vision rehabilitation options.

1. Statewide Vision Resource Centre (SVRC) nystagmus page.
   
2. Royal National Institute for the Blind (RNIB) nystagmus page.

1. Briefly describe how to locate the null point.
   
2. Make a note of the class room modifications following the location of the null point so that you can inform a child’s parents, teacher or visiting teacher. (NB: the SVRC resource is particularly helpful for this question).
   

Task 3

Your mentor at See Well Australia suggests that Zach would benefit from null-point training. Working with your group, formulate a null-point training program for Zach.
Here are some resources to get you started:

• Null point training & eccentric viewing video
  
• Fitzmaurice K. (n.d.) Null point training manual. La Trobe University.