Answers to All Questions

Parts of a Trial (Total) Box

1. Trial frame
2. Minus lenses (for myopia correction)
3. Plus lenses (for hyperopic correction)
4. Cylindrical lenses (for astigmatism correction)
5. Prisms
6. Occluder
7. Pin hole

Question 1: Discuss Adult History Taking with a Suitable Example

Components:

1. Reason for visit / Chief complaint - The primary concern bringing the patient in (e.g., "blurred vision," "headaches," "difficulty reading")
2. History of presenting complaint - Duration, onset (sudden or gradual), nature (constant or intermittent), severity, and associated symptoms
3. Ocular history - Previous eye conditions, spectacle or contact lens wear, previous eye surgery or treatment
4. General medical history - Systemic conditions (e.g., diabetes, hypertension) that affect eye health
5. Family history - Glaucoma, macular degeneration, refractive errors in family members
6. Drug history - Medications affecting vision (e.g., hydroxychloroquine causing maculopathy, steroids causing cataract/glaucoma)
7. Social history - Occupation, hobbies, driving requirements (helps determine visual demands and management goals)

Suitable Example:

• Chief complaint: Difficulty reading small print and computer work
• HPC: Gradual onset over 6 months, both eyes, worse at end of day, holding things further away to see clearly, no pain or redness
• Ocular history: Wore reading glasses since age 42, last eye test 2 years ago
• Medical history: Hypertensive, on amlodipine
• Family history: Mother had glaucoma
• Social: Works 8 hours/day on computer; drives

Question 2: VA Recording, Documentation, and Delayed Milestones

Visual Acuity (VA) Recording

• Snellen notation: e.g., 6/6 (metric) or 20/20 (imperial) - patient reads at 6m what a normal eye reads at 6m
• LogMAR notation: e.g., 0.00 (equivalent to 6/6), 0.30 (6/12), 1.00 (6/60) - preferred in research and clinical settings for statistical validity
• Decimal notation: 1.0 = 6/6, 0.5 = 6/12

• RE: 6/6 (20/20) N5 @ 40cm
• LE: 6/9 (20/30)
• BE: 6/6
• Recorded with: sc (without correction), cc (with correction), ph (with pinhole), or VA cc Rx / NVAcc

LogMAR Partial Line Scoring:

• e.g., reads 5/5 on 0.8 line + 3/5 on 0.7 line → VA = 0.8 - (3 × 0.02) = 0.74

Delayed Milestones in VA Documentation:

• Lower than age-expected norms
• Recorded alongside developmental context (e.g., preferential looking tests, Cardiff cards, Kay pictures)
• Compared against normative values for age

• Birth: light perception only
• 3 months: fixes and follows
• 6 months: ~6/60 (fixates on faces)
• 1 year: ~6/18
• 3 years: ~6/9
• 5 years: 6/6 (adult level)

Question 3: Pediatric History Taking - Birth History & Questions During Examination

Pediatric History Taking Framework

1. Was the pregnancy full-term or premature? (Prematurity is a major risk factor for retinopathy of prematurity, amblyopia, strabismus)
2. Were there any complications during pregnancy? (e.g., maternal infections - rubella, toxoplasmosis - can cause eye defects)
3. Was the birth normal/vaginal or caesarean?
4. Did the baby require NICU admission or oxygen therapy? (High O₂ in neonates → retinopathy of prematurity)
5. Birth weight? (Low birth weight associated with eye problems)
6. Was there any jaundice requiring phototherapy?

1. Does the child hold objects close to their face?
2. Does the child sit too close to the TV?
3. Have teachers noted any difficulty seeing the board?
4. Does the child have an eye turn (squint/strabismus)?
5. Does one eye close or squint in bright light?
6. Are there any concerns about the child's vision from parents/teachers?
7. Has the child been treated for lazy eye (amblyopia)?
8. Any history of patching or glasses?

• Squint, amblyopia, refractive errors, retinal dystrophies, congenital cataracts in family members?

1. Can you see the butterfly/picture? (For fixation during retinoscopy)
2. Which one is clearer - this one or that one? (During refraction, using pictures not letters)
3. Can you point to this letter/picture? (For children who cannot verbalise)
4. Which looks blurry? (To assist with duochrome/fogging tests)
5. Does anything hurt? (Rule out corneal abrasion, foreign body)
6. Ask parents: does the eye turn when the child is tired or unwell?

Question 4: VA Calculation - Patient Reads 3/5 Letters on 0.8 LogMAR Line

Calculation:

• Each letter = 0.02 log units
• The line score is the LogMAR value of the top of that line minus credit for each letter read correctly

• The patient reads 3 out of 5 letters on the 0.8 LogMAR line
• The next line (easier, higher VA) is 0.9 LogMAR (assuming they read this fully) - but we are told they are on the 0.8 line

VA (LogMAR) = Line value - (number of letters read correctly on that line × 0.02)

VA = 0.8 - (3 × 0.02) = 0.8 - 0.06 = 0.74 LogMAR

• 0.74 LogMAR ≈ 6/33 (approx), between 6/30 and 6/36

Question 5: Steps Involved in DVA (Distance Visual Acuity) Assessment

Steps for Distance Visual Acuity Assessment:

1. Ensure the chart is properly illuminated (well-lit, standardised illumination; LogMAR charts should be 80–160 cd/m²)
2. Confirm the correct test distance (typically 6 metres for Snellen; 4 metres for many LogMAR charts)
3. Use a mirror system if room is smaller than 6m (chart at 3m with mirror = effective 6m)

1. Seat the patient at the correct test distance with their usual distance spectacles (record as VA cc) or without (record as VA sc)
2. Occlude one eye (use an occluder - ensure no peeking)
3. Test the right eye first by convention
4. Ask the patient to read the chart from the top (largest letters) downwards
5. Encourage guessing - patients often under-read due to hesitation
6. Record the smallest line read correctly (for Snellen) or apply letter-by-letter scoring (for LogMAR)
7. Repeat for the left eye
8. Test binocularly if required
9. If VA is reduced, perform pinhole test to distinguish refractive error (improves with pinhole) from pathology (does not improve)
10. Record using correct notation (e.g., RE: 6/6, LE: 6/9 sc; or LogMAR RE: 0.00, LE: 0.18)

• Note: eye tested (RE/LE/BE), correction worn (sc/cc), test distance, chart type, any special conditions (e.g., dilated, difficulty cooperating)
• Example: VA cc: RE 6/6, LE 6/9, BE 6/6 - Snellen @ 6m