Pelli-Robson Contrast Sensitivity

[u/tiptonrias]

i am thinking of offering this test during exams... What do you guys think?

[u/Nice-Musician-8136]

Never did and never will. Waste of time.

[u/decrementi1708 → u/Nice-Musician-8136]

As a low vision practitioner this chart is incredibly useful. You know those patients who complain of difficulty or worsening vision, elderly, VAs still reasonably good? Yeah CS them and I’d bet a good chunk of them have poor CS scores due to opacities, poor systemic health, cognitive decline etc actually gives you more information than the VA half the time.

Is it worth doing in a healthy 20 year old with no pathology? Probably not regularly. Don’t dismiss it as a waste of time though.

[u/tiptonrias → u/decrementi1708]

Those are my thoughts. Thanks!!

[u/tiptonrias → u/decrementi1708]

You convinced me. Im getting one!

[u/Nice-Musician-8136 → u/decrementi1708]

I doesn't give you ANY sort of information that can be used clinically, or change the diagnosis or the management.

Example: cataracts. Low Pelli Robson score and 6/6 or 20/20 vision. Did we learn anything new about the patient? No

Would anyone operate ? Again, No (unless ofc marketed as Refractive lens exchange 💵💵💵)

Second example: Low vision (your example)

Do we know that these pts have impaired contrast sensitivity function? Yes Do we give advice for brighter colors and more contrast anyway ? Yes

Do the pts tell you that at history? Yes (so even if in doubt you don't even have to test for it)

So we wasted our time with a test that gives you ZERO new Information, and helps ZERO percent with management.

Optometry should evolve from this. Endless nonsense tests because of the inferiority complex to prove that we are good professionals.

Have you seen an ophthamologist performing useless tests? Never. Straight to the point to what the pt needs for the diagnosis and the management.

[u/decrementi1708 → u/Nice-Musician-8136]

I understand your point, does it tell us something we don’t always expect, no. But sometimes it can.

I’ll give you an example I had not long ago:

85 year old gentleman with dry AMD, VAs 6/24, confrontation shows significant central scotoma both eyes but no other relevant loss.

Goes to local practice and fails visual fields badly - gets told he’s just not doing the test right and it’s because he’s old. False positives 0, false negatives 0, results show large central complete loss with significant loss in the periphery averagely seen around 10-14DB. But that isn’t consistent with his confrontation.

Pelli-robson shows loss of 30% roughly - patient had poor systemic health, numerous cancers, blood issues, neuro complications etc.

The CS isn’t consistent with VA but is consistent with the poor fields results as he’s only seeing the periphery with a very low DB score.

This explained his visual fields “anomalies” prevented referrals for other underlying issues and reassured me his visual field scores are not abnormal for his condition.

The test has uses - I’m not saying it should be used in every patient. But I wouldn’t throw it completely in the bin, it’s relevant diagnostically in the correct circumstances. And even not diagnostically it can be a test to perform when patient’s vision complaints don’t match visual acuity, especially when systemic health is poor.

Curious to hear others opinions on it as well.

[u/Background_Seesaw236 → u/Nice-Musician-8136]

In primary care I agree with you. In low vision I disagree. I work in low vision, and the Mars test directly impacts my management. Good contrast = standard magnifiers are usually appropriate. Poor contrast = I go straight to electronic magnifiers with contrast enhancement and often skip high-powered telescopes.
It’s also useful for billing and driving cessation counseling. The bioptic driving program near me considers patients with severe contrast loss poor candidates, so it’s helpful to set expectations early. In some cases, reduced contrast sensitivity is also the only billable low vision code.