Author Topic: Questions about Snellen chart  (Read 5811 times)

Offline OtisBrown

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Re: Questions about Snellen chart
« Reply #15 on: April 15, 2013, 07:12:24 AM »
Dear Aparna,

Subject: I agree that the plus must be "comfortable" and understood.

The key issue ( which is admittedly difficult ) is to have the child "push" the reading away - so that the child is reading at the "just blur" point.  That is the real issue, and that is why a +1.5 can be as effective as a +2.0 - if used correcty.



Thanks John and Otis. It helps clarify where we stand now.
John, we asked him to wear atleast the +1.5 in school as he forgets to put his chin on his hand sometimes.
Just trying what we can to prevent it from getting worse.

Offline OtisBrown

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Re: Questions about Snellen chart
« Reply #16 on: April 15, 2013, 07:18:53 AM »
Subject:  Preventing it from "getting worse".

Regarding:  Getting to a point, where you can avoid wearing any minus lens.

One thing is certain - if he wore that -4.75 diopters, it would get profoundly worse.

But I am always an optimist.  I would included getting his Snellen clear - to the extent that both of you verify 20/60 on your own Snellen.  Don't pressure the child - but have it up.

My goal would not be to "stop it from getting worse" - but to "get out of it" at a reasonable level - at to avoid wearing a minus lens.  I think that is possible.  If he gets to 20/60, then the real goal, of getting to 20/40 (and better) is possible.  But I do agree to all the difficulties of doing this.

Offline johnlink

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Re: Questions about Snellen chart
« Reply #17 on: April 15, 2013, 09:26:44 AM »
John, we asked him to wear atleast the +1.5 in school as he forgets to put his chin on his hand sometimes.

Since he can read at 10 inches with a +2.00 lens with a +1.50 lens it is important that he read at 11 inches or more.

Al of my advice is based on the idea that extended periods of close work ought to be done at the edge of blur.