Paper presented by Marion Blazé - Visiting Teacher for Vision Impaired, Statewide Vision Resource Centre, August 11, 2000

Visiting teachers have all observed huge variation between skills of vision impaired students who use magnifiers. There are many non-users, some refusers, those who use them for reading labels and diagrams only and some who read everything with them. I knew one senior student who ‘wore’ his magnifier in his eye socket and used it to read everything!

So, why should students use magnifiers?

Disadvantages for users of large print

• Enlarging can emphasise the imperfections in print
• Pictures are in black & white ( and shades of grey)
• Labels on graphics or maths symbols may need further enlargement
• Large print is not readily available post school - students may become non-functional readers
• Large print books are very bulky, especially textbooks

Advantages for users of large print

• Little or no instruction is needed to use LP
• A Low Vision Clinical evaluation is not required for LP
• Student may be less self-conscious when reading LP (doesn’t need to use any special aids)
• LP books are funded by Resource, whereas parental or other funding is required for magnifiers

Disadvantages for users of magnifiers

• Magnifiers must be prescribed by Optometrist
• Magnifiers and clinical appointments are usually funded by parents
• The cosmetics of magnifiers may cause self-consciousness
• Optical problems associated with the optics of magnifiers need to be tolerated
• Instruction is required in use of magnifier
• Some time and commitment is required if student is to attain skill
• Reading speed and comprehension will probably be reduced in early stages of use

Advantages of Magnifiers

• Magnifiers allow immediate access to print anywhere
• Maps and graphics can be viewed in true colours
• Lower overall cost per child than LP
• Lighter and more portable than LP
• No ordering and waiting time for materials
• May be more cosmetically desirable than using huge books
• Allow greater independence (and choice in reading materials!)
• Can be used post school

What does research tell us about the efficiency of using magnifiers or large print?

• no significant difference in reading rates and comprehension found between individuals using large print and those using regular print with magnifiers (Corn, 1990)
• another study did find that reading speed declined with greater magnification
• shorter saccades lead to an increased number of fixations and slower reading speeds (Fotinakis & Dickinson, 1994)
• students with retinitis pigmentosa achieve better reading speeds when using cylindrical mirror magnifiers (with only vertical magnification) (Spitzberg, Goodrich & Perez-Franco, 1994)
• particular eye movements adopted by readers using magnifiers have greater influence on both speed and comprehension (Fotinakis & Dickinson, 1994)
• implications for teaching effective technique (Fotinakis & Dickinson, 1994)
• yet another study found that students who used magnifiers were more likely to progress beyond a ‘year 8’ reading level than those who used LP (Corn, 1990) This may be because the type of students who adapt to magnifier use are more likely to be brighter or more diligent students.

Prescription of magnifiers by an optometrist

These include:

• What is the intended purpose for the aid? - for reading books, labels, textbooks, just for maths, dictionary, telephone books, etc.
• What is its focal distance? (Distance from magnifier to page - see focal distance table.) - this is a fixed distance for stand or bar magnifiers.
• At what distance should the aid be held from the eye?
• Should it be used with or without spectacles?
• Is it intended as a monocular or binocular aid?
• Should the student have one eye closed or both eyes open? (For young students, the muscular strain of closing one eye can cause distortion in the open eye which may not be desirable. It may be preferable to leave both eyes open even while looking through a monocular aid.
• With which eye should the student use the aid?
• What magnification does it provide?
• (N.B.: Magnification = dioptres divided by 4. See table about magnification.)
• With what print size should the aid be used?
• What instruction has student already been given?

Focal distance chart

(Foundations of Low Vision pp129)

The ‘mechanics’ of reading with a magnifier

If the optometrist prescribes a magnifier to be used with spectacles, we need to ask if, for sustained reading it can be used without spectacles to decrease the distance from the eye to the magnifier.

Eye-hand coordination is another important skill for a magnifier reader and is one of the reasons that magnifiers are not often prescribed to children below about year 3. (The other reason being that young children can accommodate so close that they often get sufficient magnification from bringing the print very close.) Movement of an unsteady hand is ‘magnified’ on the page. The magnifier lens must remain parallel to the page. Any tilt will exaggerate lens aberrations. This may not be immediately apparent to a student with low vision.

Another important skill involves tracking and eye movements. Efficient, mature readers utilise smooth, rightward saccades with few regressions. Low vision readers using magnifiers have been found to adopt ‘saw-tooth’ eye movements. These are caused by the eye following the apparent leftward movement of the print as the magnifier is moved to the right. The ‘saw-tooth’ movement lowers reading speed and comprehension and increases fatigue (Fotinakis & Dickinson, 1994). Any training must attempt to minimise this. Also, the velocity of smooth eye movements must be well matched to that of the moving letters under the magnifier, otherwise comprehension is lost.

Lighting must also be considered. The magnifier may occlude light so the student must be made aware of where to position himself in relation to light when using the magnifier.

The teaching of reading with a magnifier

I stress again the importance of teaching the student about the mechanics of reading with a magnifier. Students must understand how to find the focal distance and how to vary their perceptual span. One optometrist suggests attaching a piece of string to the magnifier with a knot to indicate how far it should be held from the page. The student should also understand the implications of and the need for smooth, rightward eye movements. You should also explain that initially reading may be slower as the student concentrates on use of the device rather than the reading task.

Should the student move the page or move the magnifier and eyes? This depends on the task and the type of material. It is OK to move a single page flat on a table top or reading stand. This becomes a bit too difficult with books.

The student will need to do some reading exercises with the magnifier to build up their skills. I would not recommend isolated letter or word exercises as the student should be trying to maximise his/her perceptual span.

Start with the print size recommended by the optometrist. Try larger print if the student is not coping, or go smaller if s/he is coping well. The student should be able to reduce the initial print size with practice.

The first exercise should comprise short phrases, well spaced between columns and lines. (See reading exercise charts.) The student can start with one column, moving to several columns, practicing smooth rightward movements. We should always try to spark the interest of our students. Make up phrases which will amuse, take phrases from a favourite book or pick a pet topic e.g. football.

If the student has difficulty tracking, use an ‘aperture’ - a piece of cardboard which occludes all but one line of print. First use a black aperture on white paper, then grey, then a fine line under the print, then a ‘white’ mask so the student is reading only one line. (Use white cardboard on the white page to occlude all but the one line without giving a contrasting aperture.) This will move the student away from concentrating on the aperture for tracking, and onto tracking the line of print.

Use a pointer at the beginning of the line, if movement from one line to the next causes difficulties.

Move to columns of text (of interest to the student). For this, one can use magazine articles about footy stars, kids magazines articles or any short, factual, interesting stories. Again use ‘apertures’, if needed. Aim not to use these permanently as the magnifier is enough to handle.

Finally, move to normal reading materials. Hard backs are easier than paper backs as the student needs to sit the book flat and paper backs don’t open absolutely flat. As manual skills increase, give the student a specific purpose for reading (e.g. find out answer to question) so that his/her focus moves away from the magnifier and onto the reading task.

Reading Exercise Chart

Link to Harry Potter reading exercises

Increasing reading speeds

Oral & silent reading rates (in words per minute)

Year level reading rates	Minimum oral reading rates	Typical silent reading rates
1	60	less than 81
2	70	82-108
3	90	109-130
4	120	131-147
5	120	148-161
6	150	162-174
7	150	175-185
8		186-197
9		198-209
10		210-224
11		225-240
12		241-255

(Foundations of Low Vision pp259)

Reading rates for people with low vision (in words per minute)
 

(Foundations of Low Vision pp284)

Teachers often believe that low reading rates are a natural outcome of having low vision and hence do not attempt to provide training to improve skills. Suggesting that the low vision student does every second question or reads fewer books because of time limits, whilst often practical, perpetuates the low vision student’s poor skills and stamina and disadvantage in exposure to reading. Good readers become so through reading!

Strategies for increasing reading fluency and speed

Repeated readings:

• short, interesting stories (3-5 min.)
• read and time
• re-read and re-time
• make student aware of rate increase
• repeat several times

Paired reading:

• choose classmate with similar reading level but faster rate
• have VI student read a passage on own (silently will do)
• let classmate read passage aloud while VI student follows text
• then two read together
• VI student will try to match speed of classmate

Choral reading:

• select easy reading material for a small group of children including VI student
• read aloud together
• since no-one is ‘on stage’ this is a comfortable way for slower students to try to match speed of faster readers

Echo reading:

• similar to choral reading, but teacher and student read together
• direct student to disregard meaning and concentrate on smooth eye movements
• teacher gradually increases rate of reading as passages are repeated

Fatigue

• take short breaks
• close eyes
• look into distance
• change task - listen to audio book for a while
• shift physical position of arms, neck, back, shoulders, etc.

Graphics

For graphs, the student needs to look at it without the magnifier first. Although the student won’t see detail, s/he can see the overall shape of the graph. If you use a photocopy of graphs in books, the teacher can circle specific parts to teach certain concepts. Again, the student may need an ‘aperture’ to track to points. Also, as with tables, ensure that the student understands the conventions of labels on graphs. There are some good mainstream books available to teach graphing skills. Use these as part of your student’s magnifier training, if the student requires this.

For pictures and diagrams, again it helps to look at diagrams without the magnifier first. Diagrams are difficult to perceptualise in small chunks and there are few conventions to rely on. The student’s instructions may need to be specific to individual diagrams. For example, instruct the student to use the key, read labels and follow arrows to diagram part, whether the diagram is shown with or without perspective.

The beauty of using a magnifier with diagrams is that the student can use the colour copy instead of a black & white enlargement.

What to tell teachers when your student reads with a magnifier

Teachers need to know that, whilst the aid will solve many problems it may create a few, too. Visual and postural fatigue may be increased at least in the early stages of using the magnifier. The student’s field of view will be reduced by the aid. This is especially important when viewing graphics.

Conclusion

References

Corn, A. & Koenig, A. Ed., Foundations of Low Vision: Clinical & functional perspectives, AFB Press, New York, 1996

Fotinakis, V. & Dickinson, C., ‘Reading with magnifiers’ in Low Vision - Research & new developments in rehabilitation by Kooijman, Looijestijn, Welling 7 Wildt, IOS Press, Netherlands, 1994

Spitzberg, L., Goodrich, G. & Perez-Franco, A. ‘Reading with vertical magnification with Retinitis Pigmentosa’ in Low Vision - Research & new developments in rehabilitation by Kooijman, Looijestijn, Welling 7 Wildt, IOS Press, Netherlands, 1994

Marion Blazé
Statewide Vision Resource Centre
 

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