Low Vision Final Study Guide Part 2 Flashcards
Assistive technology/Optical devices & ADL's & Adaptive Equipment
Assistive technology/optical devices
Define the term “magnification.”
The process of enlarging the apparent size not physical size of something
Assistive technology/optical devices
Describe what is meant by “relative distance magnification.”
If you move** closer** to the object, the object becomes **relatively bigger **
Assistive technology/optical devices
Describe what is meant by “relative size magnification.”
- Size of object is made larger
- If viewed at the same distance, it appears relatively larger
Assistive technology/optical devices
How does angular magnification work?
- achieved using am optical lens
- makes objects at a distance appear closer to the eyes, therefore larger.
Assistive technology/optical devices
What shape of lens do angular magnifiers use?
Traditional magnifiers use convex lenses
Assistive technology/optical devices
What will happen if a visual object falls outside of the focal range of a magnifier?
If an object is outside the focal range, it will appear upside down.
Assistive technology/optical devices
What is the name for the visible area inside the magnifier?
Field of view
Assistive technology/optical devices
What are the three general rules of magnifier strength?
- shorter the focal distance
- smallest field of view
- heavier the magnifier
Assistive technology/optical devices
Describe the proper technique for positioning a magnifier.
It is okay to hold the magnifier anywhere in relation to the ye as long as the object being viewed is within focal distance of the magnifier.
* focal distance must be maintained
* viewing distance can be flexible
Assistive technology/optical devices
The refractive strength (power) of a magnifier is measured in what units?
Refractive strength of lens is measured in diopters (D)
Assistive technology/optical devices
Be able to calculate the diopter strength of magnifier given its focal length.
Divide by 100 by the focal length of the magnifier.
100/5= 20 diapters of strength
Assistive technology/optical devices
Are X-units equivalent to diopters?
- Strength of magnifiers is sometimes given ‘X Units’ instead of diopters
- There is NO standardization of X units, however, 1X = approximately 4 diapters
Assistive technology/optical devices
Should a person wear their eyeglasses when using a magnifier?
Yes!! Person should always wear their eyeglasses when using any magnifier
Assistive technology/optical devices
Be able to tell if an eyeglass prescription corrects for nearsightedness or farsightedness.
- Concave lens- Corrects for myopia (nearsighted)
- Helps see things in distance
- Convex lens- Corrects for hyperopia (farsighted)
- Helps see thing near
Assistive technology/optical devices
Know the proper technique for using a handheld magnifier.
- Find the focal distance
a. Begin by laying the magnifier on the page, then pulling it away until the print comes into focus - View through the distance portion of eyeglasses (if worn)
- Move the magnifier across the line of text you are reading
- Trace the line just read back to the left side of page
- Drop down to next line of text
Assistive technology/optical devices
What are the advantages of using a stand magnifier.
- Self-maintains the focal distance
- Can use stronger powers
- Less hand strength and coordination
Assistive technology/optical devices
Know the proper technique for using a monocular telescope.
- Locate the target without using the telescope
- Bring the telescope to the eye
- Hold the telescope as close to the eye as possible
- Stabilize the support arm
- Blur out the object, then slowly bring it into focus
- If client has difficulty locating target, you can eliminate all light sources except telescope window, occlude the other eye, occlude peripheral vision in viewing eye.
Assistive technology/optical devices
What are some considerations for recommending a desktop CCTV?
- Requires dedicated space (not generally portable)
- Requires practice – person must now look up at screen while reading or writing instead of down
- Ergonomics – how to setup to support sound body mechanics
- Cost – Expensive
Assistive technology/optical devices
What are some considerations for recommending a portable electronic magnifier?
* Screen size may not accommodate all text, depending upon how large – Means person may have to move device around
* Often not efficient for handwriting tasks
* Typically for near tasks only, no distance viewing
* Must remember to charge device (also where it was placed)
* **Cost **– Midrange
Are ADLs and IADLs equally impaired by low vision conditions? Why?
**IADLs are more impaired **by low vision conditions than basic ADLs because they are more vision
dependent.
Should the initial OT evaluation only focus on ADL and IADL performance? What additional 2 factors should be included?
No – Goes beyond ADLs and IADLs to address self management of chronic diseases and safety
Be able to provide examples of secondary safety factors for assessment.
1. Factors that increase risk for disability
– High blood pressure
– Smoking
– Sedentary lifestyle
– Obesity
– Nutrition
– Falls
– Depression
2. Safety
– Ability to accurately identify medications
– Spoiled food/food safety
– Dial emergency numbers
3. Emergency procedures
– Dialing 911 and emergency contacts
– Fire evacuation
– Severe weather safety
4. Unsafe areas of house
– Poor repair
Is the R-SRAFVP an objective assessment? How is ADL performance assessed by the R-SRAFVP?
- No – Subjective
- Administer is a quiet environment – 20 minutes to administer
- Explain the rating scale to the client
– May want to develop a cheat sheet - Describe each ADL task – description is included with the form
- Instruct the client to rate ability to complete the task using the rating scale
- Circle the corresponding number
- If there is a discrepancy in reporting – complete the observational assessment, observation is
confirmatory
Be able to select an appropriate interview and observational task for assessment of blood pressure, smoking, and medication management.
Blood Pressure
* Interview
– Tell me your average blood pressure reading?
– How often do you measure your blood pressure?
– How do you measure and record your blood pressure?
– Tell me why it is important that you control your blood pressure?
– What medication do you take to control your blood pressure?
– Tell me about health behaviors you follow to help control your blood pressure
* Observation
Smoking
– Have client demonstrate use of home blood pressure cuff and method to record reading.
* Interview
– Do you smoke?
– What do you smoke?
– How often do you smoke or how many cigarettes do you smoke daily?
– How long have you smoked?
– Why do you smoke?
– Tell me why you think it is important to not smoke?
– Have you tried to quit smoking in the past? What have you tried in order to quit?
– Would you like to quit smoking?
* Observation
– If possible, observe safety of smoking- attending to ash, attending to cigarette disposal.
Medication Management
* Incorporates subjective information and direct observation of medication taking behavior
– Knowledge of medications
– Ability to take medications
– Ability to procure medications