eyescope

My dusty 1998 Edmund Scientifics catalog, there is an item called an
eyescope.
It says that you can "see the inside of your own eye".
Apparently they no longer sell it
I see a similiar item, no longer available:
http://boreal.com/category.asp_Q_c_E_537867

Do you know where to purchase an eyescope (or the equivalent)?
Can you see the retina?
Can you see the optic nerve?

bill

On 1 Mar 2007 15:04:15 -0800, bill wrote:

> My dusty 1998 Edmund Scientifics catalog, there is an item called an
>eyescope.
>It says that you can "see the inside of your own eye".
>Apparently they no longer sell it
>I see a similiar item, no longer available:
>http://boreal.com/category.asp_Q_c_E_537867
>
> Do you know where to purchase an eyescope (or the equivalent)?
>Can you see the retina?
>Can you see the optic nerve?
>
>bill
I have an eyescope from Edmund Scientific. I bought it out of
curiosity and not as a substitute for an ophthalmologist's exam. It
contains a battery and light bulb, a parabolic mirror, and a very
small lens. They claim that it forms a virtual image of the inside of
your eye. An instruction booklet shows typical images of healthy and
unhealthy eyes. They state that it is not a diagnostic tool, but a
means of self-examination, like a mirror.
I can see lots of floaters in my eyes. Also I can see the scleral
buckle in one eye from a 1976 operation for retinal detachment. I
cannot see the optic nerve. The images do not have enough resolution
to see any detail.
Since I'm not a doctor, I cannot interpret what I have seen any better
than I've stated.

Uncle

>,
> The only
> way you could see the inside of your own eye is to have someone take a
> photo of it:
>

Dear Dr. Stacy,

Not exactly true. There are entoptic phenomena where the eye can
see within the eye. For example, a patient having a slit lamp exam
can momentarily see his retinal vasculature. Or the observation of
white cells against a blue (say sky) background has been documented.
And there is the blue arcs phenomena (Purkenje) that one doctor has
proposed (patented) a means of observing glaucoma changes. Etc.
So....depends how you define see.

Don W

On 3/2/07 7:49 AM, in article
(E-Mail Removed) om, "Don W"
<(E-Mail Removed)> wrote:

>> ,
>> The only
>> way you could see the inside of your own eye is to have someone take a
>> photo of it:
>>
>
> Dear Dr. Stacy,
>
> Not exactly true. There are entoptic phenomena where the eye can
> see within the eye. For example, a patient having a slit lamp exam
> can momentarily see his retinal vasculature. Or the observation of
> white cells against a blue (say sky) background has been documented.
> And there is the blue arcs phenomena (Purkenje) that one doctor has
> proposed (patented) a means of observing glaucoma changes. Etc.
> So....depends how you define see.
>
> Don W
>
>
>
>
Sometimes, I see the vasculature spontaneously without trying. I do not
remember the exact conditions.

Bill
-- Fermez le Bush--about two years to go.

Uncle,
Does the eyescope view the eye directly, or are you looking at a
projection of the eye, similiar to this:
http://www.exo.net/~pauld/summer_ins...ur_retina.html

thanks,
bill

On Mar 2, 7:26 am, Uncle <u...@erehwon.inv> wrote:
> On 1 Mar 2007 15:04:15 -0800, bill wrote:
>
> > My dusty 1998 Edmund Scientifics catalog, there is an item called an
> >eyescope.
> >It says that you can "see the inside of your own eye".
> >Apparently they no longer sell it
> >I see a similiar item, no longer available:
> >http://boreal.com/category.asp_Q_c_E_537867
>
> > Do you know where to purchase an eyescope (or the equivalent)?
> >Can you see the retina?
> >Can you see the optic nerve?
>
> >bill
>
> I have an eyescope from Edmund Scientific. I bought it out of
> curiosity and not as a substitute for an ophthalmologist's exam. It
> contains a battery and light bulb, a parabolic mirror, and a very
> small lens. They claim that it forms a virtual image of the inside of
> your eye. An instruction booklet shows typical images of healthy and
> unhealthy eyes. They state that it is not a diagnostic tool, but a
> means of self-examination, like a mirror.
> I can see lots of floaters in my eyes. Also I can see the scleral
> buckle in one eye from a 1976 operation for retinal detachment. I
> cannot see the optic nerve. The images do not have enough resolution
> to see any detail.
> Since I'm not a doctor, I cannot interpret what I have seen any better
> than I've stated.
>
> Uncle

> > Don W
>
> Sometimes, I see the vasculature spontaneously without trying. I do not
> remember the exact conditions.
>

Well, if for some reason the light may enter the eye so as to be
reflected off the inside of the eye so as to move the shadow off its
normal position, then the "new" shadow can be seen. The text Bennett
and Rabbett, "Clinical Visual Optics" shows this in one of their
figures. But the conditions have to be just right. Like not too much
"other" light.

Don W.

On 2 Mar 2007 11:29:25 -0800, bill wrote:

>Uncle,
> Does the eyescope view the eye directly, or are you looking at a
>projection of the eye, similiar to this:
>http://www.exo.net/~pauld/summer_ins...ur_retina.html
>
>thanks,
>bill
>
It most likely works on the same principle as your above link shows.
The eyescope surface that goes in front of the eye is dull black
surrounding the light, which is very small and dim. So the image must
be formed on the dull black surface.

Uncle

On Mar 2, 5:51 pm, Uncle <u...@erehwon.inv> wrote:
> On 2 Mar 2007 11:29:25 -0800, bill wrote:
>
> >Uncle,
> > Does the eyescope view the eye directly, or are you looking at a
> >projection of the eye, similiar to this:
> >http://www.exo.net/~pauld/summer_ins...he_eye/seeing_...
>
> >thanks,
> >bill
>
> It most likely works on the same principle as your above link shows.
> The eyescope surface that goes in front of the eye is dull black
> surrounding the light, which is very small and dim. So the image must
> be formed on the dull black surface.
>
> Uncle

I was under the impression that the upper surface (of the Edmund
Scientific device) was a reflective concave mirror. And it used that
kind of optics for the viewing. Truth??

Don W

Uncle wrote:

> I can see lots of floaters in my eyes. Also I can see the scleral
> buckle in one eye from a 1976 operation for retinal detachment. I
> cannot see the optic nerve. The images do not have enough resolution
> to see any detail.

I don't doubt you can see floaters, as anyone with them can plainly see
them without the help from any device at all. But you cannot see your
own scleral buckle with that piece of junk, that's for sure. You're
seeing something I'm sure, but it sure as hell isn't the buckle.

w.stacy, o.d.

Don W wrote:

>>,
>> The only
>>way you could see the inside of your own eye is to have someone take a
>>photo of it:
>>
>
>
> Dear Dr. Stacy,
>
> Not exactly true. There are entoptic phenomena where the eye can
> see within the eye. For example, a patient having a slit lamp exam
> can momentarily see his retinal vasculature. Or the observation of
> white cells against a blue (say sky) background has been documented.
> And there is the blue arcs phenomena (Purkenje) that one doctor has
> proposed (patented) a means of observing glaucoma changes. Etc.
> So....depends how you define see.
>
> Don W
>

No, it's exactly true, at least with today's available instrumentation.
Entoptic phenomena are certainly "visible" in the sense that you can
"see" the shadows of structures within the eye, but you are certainly
not viewing the structures themselves (the floaters and the blood
vessels) as you would be able to do with an ophthalmoscope, a fundus
camera, or directly on the dissection table.

It's just like another entoptic phenomenon, the phosphenes of digital
pressure on the globe. You are not seeing the physically stimulated
retinal receptors that are causing the appearance of the lights, just
the projected image of them in space.

w.stacy, o.d.