A nurse is assessing a patient's visual acuity using the Snellen chart. Which finding would indicate normal vision?

20/20 vision indicates normal visual acuity, meaning the patient sees at 20 feet what a person with normal vision sees at 20 feet. Other options (20/40, 20/60, 20/100) represent varying degrees of reduced vision.

Core Nursing Explanation Key Concept Analysis: This question tests the fundamental understanding of visual acuity assessment using the Snellen chart. Visual acuity is a measure of the eye's ability to distinguish shapes and details at a given distance. The Snellen chart is the standard tool for this assessment. The notation (e.g., 20/20) is a fraction where the numerator is the testing distance (20 feet) and the denominator is the distance at which a person with "normal" vision could read the same line. Therefore, 20/20 vision is defined as normal visual acuity.

Answer Rationale: Key Point! The correct answer is 20/20 vision in both eyes. This result means the patient can see at 20 feet what a person with standard normal vision can see at 20 feet. It is the benchmark for normal distance vision. For nursing documentation and patient assessment, this is the expected finding for a patient without visual impairment.

Distractor Analysis:
Watch out for confusion! The other options all indicate some level of visual impairment.
- 20/40 vision: This means the patient must be at 20 feet to see what a person with normal vision can see at 40 feet. This is worse than normal and often the minimum requirement for an unrestricted driver's license in many states.
- 20/60 vision: The patient sees at 20 feet what a normal-sighted person sees at 60 feet. This represents moderate visual impairment.
- 20/100 vision: The patient sees at 20 feet what a normal-sighted person sees at 100 feet. This indicates significant visual impairment and may qualify as legal blindness if it is the best-corrected vision in the better eye.

Related Concepts: Understanding visual acuity is part of a comprehensive Physical assessment. Nurses also assess other aspects of vision, such as visual fields, extraocular muscle movement (EOM), and pupillary response. A finding of reduced visual acuity (e.g., 20/40 or worse) should prompt further assessment, referral to an ophthalmologist or optometrist, and consideration of patient safety in activities of daily living (ADLs) and mobility.

Concept Summary

Term	Meaning	Clinical Implication
20/20 Vision	Normal visual acuity	Standard for normal distance vision.
20/40 Vision	Mild reduction	May need correction for driving; common finding.
20/200 Vision or worse (best eye)	Legal blindness	Qualifies for legal blindness definition.
Snellen Chart	Standardized eye chart	Tool for measuring distance visual acuity.

Side-by-Side Comparison!

Assessment Tool	Purpose	Normal Finding
Snellen Chart	Distance Visual Acuity	20/20 vision
Rosenbaum Pocket Card	Near Visual Acuity	14/14 vision (or equivalent)
Ishihara Plates	Color Vision	Ability to identify all numbers/patterns
Confrontation Test	Visual Fields (Peripheral Vision)	Patient and nurse see examiner's finger simultaneously in all quadrants

Anatomy, Physiology & Pharmacology Points - The Snellen chart primarily tests the function of the central retina (macula and fovea) and the clarity of the eye's optical system (cornea, lens, vitreous). - Visual acuity can be affected by refractive errors (myopia, hyperopia, astigmatism), cataracts, macular degeneration, and diabetic retinopathy. - Some medications (e.g., corticosteroids, anticholinergics) can cause blurred vision as a side effect, which would negatively impact Snellen chart results.

Memory Tips - Think of the fraction: "Top number is YOU, bottom number is NORMAL." 20/20 means you see at 20ft what normal sees at 20ft. 20/100 means you see at 20ft what normal sees at 100ft (so your vision is worse). - Mnemonic for impairment levels: "40 can drive, 200 is blind." 20/40 is often the cutoff for driving without correction; 20/200 is the threshold for legal blindness.

High-Frequency NCLEX Topics Visual acuity assessment is a core Health assessment skill. The NCLEX-RN frequently tests: 1. The meaning of Snellen chart results (normal vs. abnormal). 2. Key Point! The priority nursing action when a patient has reduced visual acuity: ensuring patient safety (e.g., fall prevention, orienting to environment). 3. Understanding that 20/200 vision in the better eye with best correction defines Legal blindness.

Watch Out for Question Variations! - Instead of asking for the normal finding, a question might ask: "A patient has a Snellen chart result of 20/100. Which nursing intervention is the priority?" Answer: Ensure a safe environment to prevent falls and injury. - A question could combine this with medication side effects: "A patient on long-term prednisone therapy reports blurred vision. What should the nurse assess?" Answer: Visual acuity using a Snellen chart. - A pediatric variation: "When assessing a 3-year-old's vision, which method is most appropriate?" Answer: Using picture charts (e.g., Allen cards) or the "tumbling E" game, not the standard Snellen letters.

Nursing Clinical Practice Guide Clinical Scenario: You are a nurse in a primary care clinic. Mr. Jones, a 68-year-old patient with a history of type 2 diabetes mellitus (DM), is here for his annual physical. As part of your assessment, you need to check his visual acuity.

Nursing Intervention Strategy: 1. Assessment: - Explain the procedure: "Mr. Jones, I'm going to check how well you can see the letters on that chart on the wall. Please cover your left eye with this occluder and read the smallest line you can see clearly." - Position the patient 20 feet from the Snellen chart in a well-lit room. - Test each eye separately, then both eyes together. Record the smallest line where the patient correctly identifies more than half the letters (e.g., "OD 20/30, OS 20/40, OU 20/30"). - Ask about any difficulty with near vision (reading) and if he wears corrective lenses. If he does, test with them on (recording as "corrected vision"). 2. Nursing Diagnosis & Planning: If the finding is abnormal (e.g., 20/60), a potential nursing diagnosis could be Risk for injury related to impaired vision. The plan includes safety education and referral. 3. Implementation: - For a diabetic patient, a finding of reduced acuity should raise suspicion for Diabetic retinopathy. Document findings accurately and report to the provider. - Provide patient education on the importance of regular dilated eye exams with an ophthalmologist. 4. Evaluation: Evaluate the patient's understanding of safety precautions and ensure follow-up is scheduled.

Patient Safety and Precautions: - Ensure the pathway between the patient and the chart is clear to prevent tripping. - If the patient cannot see the largest letter (20/200) at 20 feet, move them closer (e.g., 10 feet) and record as "10/200" or "counts fingers at 3 feet." - Never diagnose the cause of vision loss; your role is to screen and refer.

Nursing Procedure & Medication Flow Procedure: Performing a Snellen Chart Assessment 1. Wash hands, introduce yourself, explain the procedure. 2. Have patient stand or sit with heels on the 20-foot mark. 3. Provide an occluder. Test the right eye (OD) first, then left eye (OS), then both eyes (OU). 4. Ask patient to read each line from top to bottom. 5. Record the smallest line where the patient reads more than half the letters correctly. 6. Document: OD: __/__, OS: __/__, OU: __/__ (with or without correction).

A Word from Your Senior Nurse "Remember, that Snellen chart isn't just a bunch of letters on the wall—it's a window into your patient's world and safety. A change from 20/20 to 20/40 might be the first clue to a cataract, worsening diabetes, or a medication side effect. In clinical practice, you're the detective who connects these dots. When you study, don't just memorize that 20/20 is normal; think about the patient behind the number. What does 20/200 vision *feel* like? How would you help that patient navigate their room safely? That kind of thinking builds the clinical judgment the NCLEX is testing and, more importantly, makes you a compassionate and effective nurse."