The 20/25 Paradox for MDs and PAs: When the Eye Chart Says "Fine" and the Patient Isn't
/The 20/25 Paradox for MDs and PAs: When the Eye Chart Says "Fine" and the Patient Isn't
As physicians and PAs, we trust our instruments. The Snellen chart is fast, standardized, and tells us something real about a patient's central acuity. But for some patients, that single number quietly tells the wrong story—and the patient is left to argue against their own chart for years.
Consider a patient who reads 20/25 yet sees the world through roughly ten degrees of visual field: clear in the center, gone at the edges. On paper, that patient looks fully sighted. In life, they may be legally blind. Both can be true at the same time—and our intake forms rarely leave room for that.
This is the experience Mark G. Hubers describes in his essay The 20/25 Paradox.
Why It Matters
Legal blindness has two paths, not one. A patient qualifies if best-corrected acuity is 20/200 or worse, or if the visual field is 20 degrees or less. Conditions like retinitis pigmentosa take the periphery first and often spare the center until late—so a patient can have excellent acuity and a severely constricted field. Be aware that restricted fields create safety hazards, especially when early in the journey. Such as falls off loading docks, accidents while crossing the street, difficulty driving through tunnels, or changing lanes. RP and other peripheral loss conditions include the loss of being able to see in dim or bright light, so may express difficulty in movie theaters, or bars. This is often the first sign of RP.
The trouble is that acuity is almost always what gets tested first, recorded, and carried onto every form: insurance, disability, accommodations, license renewals. When the field number never makes it onto the page, a patient who is legally blind can spend a year fighting for a single piece of documentation—sometimes inside a specialist's own office.
A patient who reads the chart can still be unable to see the room it hangs on. Our job is to make sure the record reflects that. Even if you don’t have visual field testing equipment, you can use simple, low cost screening to determine who needs a referral. A ruler or even a paper on the wall, with a tape on the floor, with marks that are spaced in inch increments, with a center focus dot, can alert you to potential deficits. You can learn more about hot to do these screenings in the course. Understanding the Diversity of Legal Blindness, It’s Impacts & Solutions
What We Can Do—Starting at the Next Visit
Small, concrete changes close most of this gap:
Record both numbers. Put visual field next to acuity in your note and on any form the patient takes with them. "Best-corrected acuity: ___. Visual field (degrees): ___." One extra line captures the patients acuity alone misses.
Know both legal-blindness criteria—and make sure your staff do too. If front-office and technician colleagues only recognize 20/200, a field-based patient gets stuck. A ten-minute team huddle prevents a year of back-and-forth.
Don't let strong test stimuli reassure you prematurely. Bright, large perimetry targets can be detected even as real-world peripheral vision (dim, small, moving objects) is already failing. Pair the printout with what the patient reports living through.
Listen when a patient says the equipment seems off. Many of these patients are careful observers of their own vision. If a result doesn't match the clinical picture or the patient's lived experience, it's worth a re-test rather than a reassurance.
Give patients their own data—every visit, without being asked. Per-eye acuity, uncorrected vision, field measurements, scans. Patients who manage a progressive condition make better decisions when they can see their own trend line.
Sign the legal-blindness form when the field qualifies. For an eligible patient, this is often a thirty-second confirmation. Spare them the multiple-visit campaign to get there.
A Word on Language and Effort
It helps to retire labels that describe a symptom and pretend to explain the person. "Lazy eye" tells a patient their eye is at fault when the cornea may be damaged; "legally blind with 20/25" sounds like a contradiction only because the form has one box instead of two.
It's also worth remembering what these numbers don't capture: the cognitive work a patient does to stay functional. Brains performing real-time sensor fusion and filling in a constricted field spend real energy doing it—patients often describe being drained by mid-afternoon. There's no billing code for that, but acknowledging it changes how we talk with the patient in front of us.
The Takeaway
The eye chart is a good test. It simply isn't the whole test—and for patients with field loss, it can be the one that hides the diagnosis in plain sight. Recording the field, training the team, and handing patients their own data costs us a few minutes. Not doing it can cost a patient years.
Continuing the Mission of Access and Understanding
Adaptability for Life’s cultural competence - ethics continuing education courses provide engaging and practical skills in supporting their clients with vision/hearing loss.
Approvals - Accreditations:
OHA - Oregon Health Authority - Cultural Competence CE
CEP #18180 CA Board of Registered Nursing, Continuing Education Provider
NASW-OR Nat. Assoc. of Social Workers - Oregon Cultural Competence CE
CRCC - Commission on Rehabilitation Counselors Certification - Ethics CE
Who these courses are helpful for:
Nurses, Psychologist, LCSW, LFMT, PT, OT, SLP, ND, NP, PA, MD, DDS, LPC, Chiropractor, License Professional Counselor, Marriage and Family Therapist, Dentist, Dental Technologist, Dietitian, Emergency Medical Service Provider, Home Care Worker, Lactation Consultant, Long Term Care Administrator, Massage Therapist, Medical Imager, Midwife, Naturopathic Doctor, Occupational Therapist, Optometrist, Pharmacist, Polysomnographic Technologist/Respiratory Therapist, Social Workers, Caregivers and Families.
For those seeking to enhance their skills in communicating with those who have vision or hearing loss, consider enrolling.
2-Hour Cultural Competence CE: Effective Communication with Clients Who Are Hard of Hearing
4-Hour Cultural Competence and Ethics CE: Understanding the Diversity of Legal Blindness, Impacts & Solutions
6-Hour Cultural Competence and Ethics CE: Providing Culturally Competent Healthcare for Those Aging with Dual Sensory Impairments
Each course blends over 25 years of experience in rehabilitation counseling and disability services with lived insight and real-world examples. You’ll walk away with tools that help prevent social isolation, improve connection and communication, and foster hope—even in the face of progressive sensory loss.
What You’ll Gain
Strategies to prevent social isolation and despair
Tools to support clients experiencing progressive loss
Skills to improve communication and connection
Easy, low- or no-cost accessibility techniques
Real-world examples you can apply immediately
About the Instructor
Deb Marinos, MS, CRC, LPC, is a Certified Rehabilitation Counselor, Oregon Licensed Professional Counselor, and CMBM Mind-Body Skills Group Facilitator. She brings decades of teaching experience with health care professionals and other working with individuals navigating sensory loss and disability. Her courses are designed to be interactive, helpful, and will give you more comfort in your work.
Take the Next Step
If you’re ready to strengthen your skills, deepen your empathy, and make your practice more inclusive—join Deb and Olaf on this journey.
👉 Explore the Cultural Competence & Ethics accredited continuing education courses and sign up today at Adaptability for Life
Adaptability for Life LLC
21887 SW Sherwood Blvd. STE C
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deb@adaptabilityforlife.com