Case Studies

Low Vision Resources

Case Study 1: Adult with Retinitis Pigmentosa

This is an interactive case on how to examine a patient with vision impairment

History

Patient:

A 30-year-old female, diagnosed with RP when 15 years old with gradually reducing vision over time.  She is unable to see at all at night now. She has previously not been aware of what might have been available to her and rarely went for ophthalmological review due to being scared of the outcome.  She has just booked an ophthalmological review and visual field test with the ophthalmologist she had first seen when 15yo.

She recently met someone else with RP who mentioned Vision Australia.

Question 1: Which of the following questions would be most important to ask the patient to assist with conducting a targeted low vision workup?

Further information:

She is currently working and would like to know more information about RP, recent developments in the field, what is available to her in the way of supports.  She reports struggling with travel to and from work.  She is not currently using any specific technology and is also interested in a worksite assessment.  She is needing Orientation and Mobility support and thinking about the possibility of a Seeing Eye Dog.

General Health:

Good

Family Ocular Health: 

No relevant issues

Referral source:

Self

Goals identified:

  • I want to feel comfortable to travel independently in a range of different settings
  • I want to explore getting a Seeing Eye Dog to see if it is right for me
  • I would like to be able to continue to work
  • I would like to develop my skills with meal preparation
  • I want to explore volunteering options at Vision Australia

Clinical Assessment

Refraction:

  • Unaided VA:

RE: 6/36   

LE: 6/48

  • Subjective refraction:

RE: +0.75/-1.25×175   6/24

LE: +1.00/-.75×180    6/36

VFT:

Central visual field of less than 20 degrees in diameter 

Fundus examination:

Fundus signs consistent with RP including attenuated arterioles, macula changes and peripheral bone spicule pigmentation both right and left. Fundus images taken for an on-going tracking of change.

Management:

  • National Disability Insurance Scheme (NDIS) – Preplanning support
  • Primary Service Provider – Services discussion and Canadian Occupational Performance Measure Tool used to identify goals and priorities. Main contact person.
  • Optometrist – Functional vision assessment
  • Orientation and Mobility (O&M) – Independent travel
  • Occupational Therapy (OT) – Cooking assessment and support / home assessment/ ergonomic setup
  • Employment Services – Advocacy and workplace support
  • Vision Australia library membership
  • Seeing Eye Dog Instructor (SEDI)

Outcomes

Q2: What are the diagnostic criteria for RP:

Q3: Outline the treatment and management options available for someone with RP.

Following diagnosis of a retinal dystrophy the patient should receive annual or biannual dilated fundus examination, Goldmann perimetry, ERG testing, fundus autofluorescence imaging and, if desired, the patient’s family could receive a medical genetics consultation.

In adult patients with retinitis pigmentosa the following therapies have been considered:

Medical

Vision

Aids and training

Q4: Explain the use of electronic low vision aids as part of a management plan for patients with restricted visual fields and reduced visual acuity.

One of the exciting developments in low vision is the use of new technology to provide access to information. Some involves the use of existing mainstream technology and others use purpose-built devices for low vision. Vision Australia provides a comprehensive overview on their website of how different technologies can be applied. https://www.visionaustralia.org/information/adaptive-technology

Choose the correct statement.

A summary of the devices listed on their website is below:

  • Mobile or smart phones with the following features: keypad buttons that make a noise when pressed, screens with adjustable brightness, contrast and colour, voice activated or speed dial contact lists, good size screen, lockable, easy to hang up, screen magnification software.

 

  • Ebook readers and enhanced audio books. E-readers allow fully adjustable print size and screen illumination and enhanced audiobooks include software to allow easier navigation within the book, for example the ability to place bookmarks or skip to particular chapter or sections.

 

  • Computer enhancers may range from choosing from large size hardware (monitors and keyboards) to software which enhances the screen magnification and contrast.

 

  • Computer screen readers use a voice synthesiser to convey what appears on the screen.

 

  • Electronic magnifiers like handheld video magnifiers are like portable electronic magnifying glasses that can be held over the text or page of interest to allow easier reading.

 

  • Tablets, notebooks and notetakers allow computer technology to be portable and compact.

 

  • Print scanners that convert text into audio.

 

  • Braille technologies such as braille embossers and translators and tactile refreshable braille display devices that can translate text on a computer screen to braille.

 

  • Talking GPS systems to allow pedestrian navigation in unfamiliar areas.

 

  • Large print and talking calculators may allow students to complete their maths studies.