Instructional Guidelines for Near Devices

Instructional Guidelines for Near Devices: Microscopes, Magnifiers (hand held & stand), Telemicroscopes

General Guidelines for Instruction

Make the environment as relaxed as possible. Observe the client/student and look for signs for stress such as clenched fists, shallow breathing, nervous laughter etc.. may be signs they are not ready for training. The amount to time spent at the first meeting may vary depending on factors such as fatigue or age. The first session should begin by using large-print with excellent contrast. The main objective is to enable the user to achieve success, then gradually work toward their desired print goal. Its helpful to provide the client/student with written directions to take home in case they forget something. Provide a variety of reading materials, typically found in the household, such as prescription bottles, price tags, newspapers, magazines, mail, etc. Allow the client/student to guide instruction by bringing their own materials or choosing from your materials. Provide the client/student with materials to bring home that will enable success. Practice materials should be in various sizes, fonts, and contrast, and should include single and double spaced lines. Consider the reading level as well. The client/student should be focusing their efforts on correctly using the devise and not broverwhelmed by trying to comprehend difficult material.

Goal - To read (client specified print size) utilizing a prescribed near device.

Materials:

- Device - Cleaning equipment - Lighting to include various lamps and light bulbs - Near acuity chart - Continuous text acuity chart - Reading materials of various size, font, and contrast (i.e. newspaper and grocery item prices.) - Reading stand and clipboard - Written summary for instructions for the client - Typescope - Acetate Filters Training Sequence

I. Preparation for Training A. Assemble information about the client/student 1. Medical health history 2. Eye Condition a. Pathology b. Onset c. Acuities d. Fields e. Refraction f. Prescribed low vision aides used B. Create an outline for training C. Prepare the environment (lighting) D. Gather materials

II. Initial Encounter: Discussion A. Identify the client/students goals/priorities for using the device 1. Did they bring a sample of text they would like to read? 2. Discuss typical client/student goals to elicit other desired reading tasks B. Discuss visual condition, functional implications, or visual concerns C. Eccentric viewing 1. Does the client/student eccentric view? 2. Explaining eccentric viewing, assessment (clock face w/nose as target) determine if further instruction is required D. Discuss lightening 1. Preferred or typically used lighting 2. Does vision fluctuate from day to day or morning to night 3. Are they affected by glare and in what places E. Use of low vision aids

III. Presentation of Low Vision devises A. Examine devise visually and tactually B. Describe the aid, its uses, advantages, disadvantages, and care of aid

III. Visual skills for low vision aids A. Page orientation B. Focal distance C. Fixation, eccentric viewing D. Localization E. Keeping ones place F. Eye and head movements G. Scanning H. Tracking I. Speed and ease of reading IV. Techniques Specific to Microscopes and Telemicroscopes

Note: Telemicroscopes require the user to add a cap of the objective so they can read or write. They are typically more difficult to use because of their smaller field of view, depth of focus, and apparent displacement of the material to be viewed. Students must lower their head more than it seems necessary to find the target.

A. Discuss importance of correct focal distance 1. Lower-powered microscopes, the client/student should bring materials closer to them until a clear focus is found 2. High-powered microscopes, the client/student should start by touching the material to their nose and push it away until a clear focus is found. 3. Telemicroscopes: typically have an increased working distance B. Client/student should look directly though the center of the lens C. Materials should be on a flat surface D. Materials should be scrolled before the eye (moving your head or eyes will change The focal distance resulting in blur or distortion

V. Problem Solving for Microscopes/Telemicroscopes A. Material out of focus 1. Check proper focal distance and reinforce 2. Check that material is flat. (Use clipboard)

B. Postural Fatigue 1. Try a reading stand 2. Change seating to firm back and arm support C. Asthenopia 1. Shorten reading times or allow for frequent breaks 2. Reinforce eccentric viewing 3. Check to see if binocular system is used, investigate monocular use or occlude D. Losing place while reading 1. Use typoscope or finger and reinforce scanning technique 2. Practice eccentric viewing E. Double vision 1. Occlude poorer eye 2. Possible need base in prism or amount of prism checked 3. Are they using a bifocal: check they are not looking though the edge of the lens F. Distortion 1. Check position and orientation of material 2. Clean lens 3. Limit eye movements and head movements 4. Reminder materials should be scrolled before the eye G. Glare 1. Change direction of lighting 2. Use a typoscope 3. Investigate acetate filters H. Dimness of reading material 1. Bring lighting closer to material 2. Get rid of shadows 3. Use yellow acetate filter

VI. Techniques Specific to Magnifiers

A. Focal distance 1. hand held magnifiers should be placed flat on the text and moved back until clear focus is achieved 2. Stand magnifiers should be placed directly on the material

B. Make sure client/students wear their glasses C. Discuss field of view: increases as the material and lens are brought closer to the eye D Illumination: demonstrate how to direct the source of light without causing glare or shadows. May need or use a illuminated magnifier E. Magnifier lens (hand held) should be parallel to the reading materials. The client/student line of sight must pass perpendicularly to the center of the lens (stand) F. Instruct the client/student to move their eyes and the magnifier together G. The most curved side of the lens should be held toward the eye

VII. Problem Solving with Magnifiers

A. Material out of focus 1. Check focal distance and reinforce 2. Reading material must be kept stationary 3. Should the client/student be wearing their glasses 4. The distance between the eye and the magnifier may need adjustment

B. Postural Fatigue 1. Hand held: brace arms and wrists 2. Use reading stand 3. Hand held: microscope of stand magnifier may be more effective 4. Change seating to firm back and arm support

C. Loses Place While Reading 1. Use typoscope or finger to mark place 2. Instruction on scanning 3. Instruction on eccentric viewing D. Distortion 1. Move magnifier and reading material closer to the eye 2. Magnifier must be held parallel to the materials 3. Hand held: most convex surface of the magnifier must face the eye 4. Consider a high quality or equivalent power magnifier’ 5. Reinforce looking though center of the lens

E. Small Field of View 1. Move magnifier closer the eye 2. Consider a high quality or equivalent power magnifier with a larger lens 3. Consider using microscope of equivalent power

F. Inverted Image (hand held) 1. Material is being held outside the appropriate focal distance

G. Pulling magnifier off page (stand) 1. Increase the power of the magnifier 2. The power of the bi-focal may need to be increased

H. Reflections off the lens surface 1. Consider using illuminated magnifier 2. Change direction of lamp lighting 3. Consider magnifier with anti-reflective coating

I. Glare 1. Consider magnifier with anti-reflective coating 2. Demonstrate typoscope 3. Address position and level of lighting 4. Evaluate for acetate filters 5. Reposition magnifier 6. Consider tinted magnifier

H. Dimness of reading material 1. Bring lighting closer to material 2.Use illuminated magnifier 3. Use yellow acetate filter

VIII. Termination of Training

A. Has the client/student reached their desired goal B. The client/student has reached a level where the goal can be pursued with practice and without the instructor C. The client/student has reached plateau, further instruction will not help

IX. Follow-up A. Call or visit the client/student a week after the first session B. Client/student returns to the site where skills are demonstrated 1. Skills are satisfactory 2. Skills are not satisfactory

X. Additional Training

A. A problem is identified and the instructor can provide additional training/techniques B. The client/student vision changes, change in goals, or new devices

Resources

Envision II: Vision Enhancement Program Using Near Magnification Devices Students 10 and younger Students 11 and Older

American Print House For The Blind, INC. 1839 Frankfort Ave Louisville, KY, 40206 1-800-223-1839

Chrissy Cowan and Renae Shepler. Carol Activities and Games for Teaching Children to use Magnifiers. . In Mary D’Andrea, Frances & Farrenkopf. (2000) Looking to Learn: promoting literacy for s tudent with low vision. NY, NY: AFB Press168-186

Matchinski, T., Brilliant, R. L., and Bednarski, M. Low vision near systems I: Microscopes and magnifiers. In Brilliant, Richard L. (Ed.). (1999). Essentials of low vision practice. Boston, MA: Butterworth Heinemann, 201-237.

Watson, G. & Berg, R. V. Near training techniques. In Jose, Randall T. (Ed.). (1999). Understanding low vision. NY, NY: AFB Press, 317-362.