Eye Movements Examination Examination Structure Sit on the right of the patient, your eyes and the patient’s eyes should be at the same level Speak whilst examining Ask children their age Look around the room for clues – spectacles, parents (for inherited syndromes) 1. Visual Acuity (Best Corrected) The worse eye is usually the affected one (may be amblyopic) 2. Spectacles It is easiest to estimate the script of spectacles by comparing the image of a line viewed through the lens and just around it. A distance line such as a doorway is perfect for this purpose. Hand Neutralise Minus lens → “With” movement Plus lens → “Against” movement Astigmatism Ground in Prism The image of the line through the lens has a fixed deviation away from the image of the line just around it. This cannot be compensated by moving the lens. The apex of the prism points towards the deviation. Fresnel Prism Method for easy check: turn spectacles side-on BO (CNVI palsy), BD (CNIV palsy on affected eye) 3. Inspection Have the patient fixate on a distant target- choose one line above their visual acuity Only comment on a strabismus if it is obvious (say “there appears to be an exo or eso deviation” in case the patient has a dragged macula and there is no tropia) 1. Abnormal Head Posture (AHP) Ask patient to “Please sit up straight” and stand back to inspect Face turn? In direction of action of paretic muscle Chin up / down? Up in elevator paresis, Down in depressor paresis Correct any AHP before cover tests (check for neck pathology) 2. ± Corneal Light Reflexes (Hirschberg) Shine a pen torch into the patient’s eyes and inspect the corneal reflexes. In patients with straight eyes, they should be symmetrical and lie over the same point on the cornea. In patients with strabismus, the corneal reflex of the fixing eye will lie centrally within the pupil, and the other will be displaced (1mm of corneal decentration = 15 Δ strabismus, Pupil margin = 30 Δ, Limbus = 90 Δ). Be aware that tropias can only be definitively diagnosed with cover testing. The Hirschberg test becomes more important when vision is poor (e.g. < 6 / 60 in either eye) and cover-testing is not possible. 3. Ptosis (CNIII palsy) 4. Pupils (Anisocoria) (CNIII palsy) 5. Globe Position Proptosis (axial vs. non-axial) 6. Other Nystagmus, facial asymmetry, hearing aids, scars (conjunctiva- squint surgery) 7. Ask Yourself “Could this be TED?”- proptosis, chemosis, injection, lid retraction 4. Cover-Testing Ensure the patient can fixate “Tell me if I block your view” If VA <6 / 60 can’t do cover! → Perform Hirschberg (corneal light reflexes) and / or Krimsky (corneal light reflexes through prism placed over the fixing eye) tests. The patient should wear their distance (& near) spectacles (unless they have prisms!) This helps the patient if they can’t fixate on a target uncorrected It is crucial in accommodative esotropia to test with and without spectacles Cover for tropia (manifest) Uncover for phoria (latent)

1. STRABISMUS
BY BABLI SHARMA
B.OPTOM , M.OPTOM

2. Eye Movements Examination
Examination Outline
• Visual acuity (best corrected)
• Spectacles
• Inspection
▫ Abnormal Head Posture (AHP)
▫ ± Hirschberg
▫ Ptosis?
▫ Anisocoria?
• Cover-Testing
• Ocular Rotations
• ± Saccades (Horizontal ± Vertical)
Visual acuity Abnormal Head
Posture (AHP)
Hirschberg Ptosis

3. Examination Structure
• Sit on the right of the patient, your eyes and the patient’s eyes should be at the same
level
• Speak whilst examining
• Ask children their age
• Look around the room for clues – spectacles, parents (for inherited syndromes)

4. 1.Visual Acuity (Best Corrected)
• Worse eye is usually the affected one (may be amblyopic)
2.Spectacles
Hand Neutralise
• Minus lens → “With” movement
• Plus lens → “Against” movement
• Astigmatism
Fresnel Prism
• Method for easy check: turn spectacles side-on
• BO (CNVI palsy), BD (CNIV palsy on affected eye)
Fresnel Prism

5. 3.Inspection
• Have the patient fixate on a distant target
• Choose one line above their visual acuity
• Only comment on a strabismus if it is obvious (there appears to be an exo or eso
deviation)
• Or there is no tropia
1. Abnormal Head Posture (AHP)
• Ask patient to “Please sit up straight” and stand back to inspect
• Face turn? In direction of action of paretic muscle
• Chin up / down? Up in elevator paresis, Down in depressor paresis
• Correct any AHP before cover tests (check for neck pathology)
Abnormal Head Posture

6. 2.± Corneal Light Reflexes (Hirschberg)
• Shine a pen torch into the patient’s eyes
• and inspect the corneal reflexes.
• patients with straight eyes, they should be symmetrical and lie over the same point
on the cornea.
• In patients with strabismus, the corneal reflex of the fixing eye will lie centrally
within the pupil, and
• the other will be displaced
• (1mm of corneal decentration = 15 Δ strabismus, Pupil margin = 30 Δ, Limbus = 90
Δ).
• Be aware that tropias can only be definitively diagnosed with cover testing.
• Hirschberg test becomes more important when vision is poor (e.g. < 6 / 60 in either
eye) and cover-testing is not possible.
Corneal Light Reflexes (Hirschberg

7. 3. Ptosis (CNIII palsy)
4. Pupils (Anisocoria) (CNIII palsy)
5.Globe Position
• Proptosis (axial vs. non-axial)
6. Other
• Nystagmus, facial asymmetry, hearing aids, scars (conjunctiva- squint surgery)
Ptosis (CNIII palsy)
Proptosis

8. 4.COVER TESTING
• Ensure the patient can fixate “Tell me if I block your view”
• If VA <6 / 60 can’t do cover! → Perform Hirschberg (corneal light reflexes) and
/ or
• Krimsky (corneal light reflexes through prism placed over the fixing eye) tests.
• The patient should wear their distance (& near) spectacles (unless they have
prisms!)
• This helps the patient if they can’t fixate on a target uncorrected
• It is crucial in accommodative esotropia to test with and without spectacles

9.  Cover for tropia (manifest)
 Uncover for phoria (latent)
• Perform cover, uncover tests slowly
• Hold the cover in place during the cover test for an adequate period of time
• Speak out loud “On covering the right eye, there is a small / moderate / large left
esotropia”.
• Tropia may be unilateral or alternate between eyes (fixation switches after each
cover).
• During cover testing, look closely for latent nystagmus and / or dissociated vertical
deviation (DVD).
• The uncover test is only useful if the cover test has demonstrated orthotropia in the
other eye
 Alternate Cover for Tropia & Phoria
• Perform alternate cover tests with fast “switch” (then pause) to break fusion

10. Cover-test Distance (CTD) in Primary
• If vertical deviation / height (“R over L” or “L over R”; hyper / hypotropia if 1 eye
fixing)
• And possible CNIV palsy → Perform Parks 3 step test
• If horizontal deviation in primary and possible CNVI palsy →
• Check for incomitance in left / right gaze
• ± Chin up / down for alphabet patterns (“V” pattern think of: Browns, IOOA, bilateral
CN IV palsy).
• Ask yourself where the eso or exo is worst:
Eso deviation worst (points to apex of letter) in chin-up (downgaze) = V pattern
Exo deviation worst (points away apex of letter) in chin-up (downgaze) = A pattern
Cover-test Near (CTN) in Primary
• You must use a good accommodative target (not a finger, light)
• ± Reading add

11. Notes on Cover-Testing
• Cover the fixing eye first
• Freely alternating tropia suggests similar visual acuity in both eyes
• When checking for incomitance,
• only do alternate cover test (not cover, uncover).
• Keep the patient dissociated by keeping one eye covered at all times
Prism cover test:
• Cover the deviating eye with a prism & cover,
• Move the paddle to cover the fixing eye,
• increase the prism until there is no longer refixation
• When measuring CTN with prism,
• Get the child to hold the target on your nose or
• Put a small sticker on your nose!
• When measuring DVD, place prism apex up in front of the affected eye Prism cover
test

12. 5. Ocular Rotations
• Either a fixation target or a pen torch may be
used.
• A pen torch has the advantage that corneal
reflexes can be viewed
• But some examiners don’t like this technique.
• Unlike cover testing for near,
accommodation doesn’t have to be controlled.
• Gently hold your hand out near the patient’s
chin or forehead (this “reminds” the patient to
keep their head still)
• And make your movements slow but
deliberate
• Avoid multiple passes
• The upper eyelids may need to be elevated
when the patient is in downgaze.
1.Horizontal pass (twice)- watch lids / pupils for
aberrant regeneration / Duane
2.“H” pattern
3.± Straight up / down (thyroid eye disease TED,
A/V patterns)
4.± Convergence
Ocular Rotations
“H” pattern

13. Notes on Ocular Rotations
• You must know which eye is fixing
• Grading: - 8 :eye looking in opposite direction to
attempted extreme gaze
• - 4 : eye looking in primary on attempted extreme gaze
• 0 : normal
• Say “- 2 defect of elevation in
abduction…”, not “restriction” (unless you have
demonstrated this first)
• Check ductions (cover the contralateral eye)
• If there is a defect (goes further if palsy is present, unlike
restriction)
• Record versions and ductions (in square brackets) e.g. -
4[0]
• For all muscles other than the medial / lateral rectus,
• Look for a vertical movement on cover testing at
extremes of gaze
• An up / down movement on attempted horizontal
movement is an “up / downshoot”
• For SR / IR, SO / IO over / underaction look for vertical
movement
• When alternate cover testing at the ends of the “H”
• You can only say “there is suggestion of e.g. IOOA”
• Prior to performing an alternate cover test
SR / IR, SO / IO

14. Grading and Documenting Ocular Rotations
A: Grade 0 is normal.
• For horizontal versions a grade of -4 indicates that the eye remains in primary
• when attempting to fully abduct or adduct.
B: When testing ocular movements at the extreme corners of gaze (at the ends of the
“H”),
• +4 indicates overaction to vertical,
• -4 indicates underaction to horizontal).
C: two eyes are drawn and points of gaze are graded.
Versions versus Ductions
• If ductions (monocular) have a different grade to versions (binocular),
• They are written in square brackets

15. 6.Saccades (Horizontal ± Vertical)
• Test monocularly
• Easier to inspect one eye at a time
• Use finger & pen ~20cm apart in field of expected deficiency.
• Don’t “wiggle” the targets
i. Normal (Fast)
• Occurs in restrictive disease
• up to the point of restriction
ii. Abnormal
• Occurs in neurological
• and myogenic disease
 Hypometric
• “Undershoot”
• Generalised slow saccades occur in supranuclear palsy
• Parinaud- worse up
• Progressive supranuclear palsy PSP- worse down,
• CPEO and myaesthenia gravis (“intra-saccadic fatigue”)
• Uni-directional slow saccades occur with CN palsies and INO
 Hypermetric
• Cerebellar Disease

16. THANK YOU