Ophthalmoscope diopter difficulties

[Groy]

We covered the fundoscopic exam in our clinical skills course this week and I seemed to be the only person in my class who had this problem:

When examining the retinal vasculature with a regular coaxial opthalmoscope, each student got to try on the same patient. Each of my peers had a diopter setting of about -1 to +1, and some with uncorrected vision reached the -3 to +3 range. I assumed this meant that the patient was not too nearsighted or farsighted. When I took my turn on the same patient, I could not see the vessels until about -8 or -9.

Just to make sure this was not some odd user error, I tried again on several more patients, with similar results. A few classmates and I tried together on another specific patient, and they all could visualize everything at about +1 or +2, and I had to put my settings on +15 before I could clearly visualize the optic disk, etc. I don't use any vision correction, I am not near or farsighted, and my last visual acuity test (1 month ago) was 20/20. Even our instructor was puzzled.

What is it that I'm clearly missing here? Thanks in advance!

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[DrRedstone]

You're missing the fact that ophthalmoscopes are literally the worst. Ophthalmologists hate them. Don't feel too bad if you can't get it down perfectly.

 

[Psai]

Unless you're planning on becoming an ophthalmologist, it doesn't matter.

 

[DoctwoB]

Here’s how you master the ophthalmoscope for med school. You aim it at the eye and get really close to the patients face. You say things like hmm, might be some A-V nicking, cup to disk ratio, etc.

The end. If they have a real eye issue call a real eye doctor.

 

[Groy]

Your points are all well-taken

I'll just carry on then!

 

[Doctor Strange]

I can guarantee you 95% of your classmates are lying when they say they see the fundus.

 

[curiousneuro]

With a regular opthalmoscope, I still have difficulties with non-dilated eyes. I carry the panoptic, which is plain awesome. Won't ever go back.

 

[treebeardette]

It sounds like your med school is way more rigorous about the physical exam than mine. I saw exactly one optic disc in medical school (and probably ever since I'll never use an ophthalmoscope again) and I was so shocked I immediately lost it. The rest of the time I was just happy to get a few vessels in focus. I certainly wasn't comparing diopter settings with my classmates. More likely your classmates are probably doing exactly what I did and aren't seeing much of anything important.

 

[UnicornOpt]

I'm an optometrist, and I'm pretty terrible with the direct ophthalmoscope. I'll use it on young children, mainly looking at their fovea, optic disc margins, visuoscopy, and Bruckner testing, but otherwise using condensing lenses is way superior.

If you are truly an emmetrope, then the diopter setting on your direct ophthalmoscope should equal the patient's refractive error to get a focused retinal image.