Block 10 Flashcards
What is the purpose of cover test
To asses the prescence and magnitude of phoria and tropia
Amount is determined with prism bars
Constant strabismus is seen
All the time
Intermittent strabismus is seen
Intermittently
Patient has moment of binocularity
Present during cover test
In strabismus, fixation can alternate between eyes or maintain fixation only with one eye
True
What do you record with cover test
Correction (sc, cc) Magnitude Eye (OD, OS) P or T Constant or (intermittent) Distance or near'
What is the purpose of EOM
To asses the ability to perform conjugate eye movements
What do you want the patient to inform you of during EOM
Pain or diplopia
What do you record in EOMs
Eye (OD, OS)
Ability of muscles
Diplopia
Pain
What is the purpose of Hirschberg?
To determine the position of the visual axes under binocular conditions
How is hisrchberg done
Have patient look at pen light
Then look at each eye monocularly
Then look binocularly
Angle lambda in ortho
0
Angle lambda in Exo
+
Angel lambda in Eso
-
Angle lambda in hyper and hypo
N/A
What is krimsky?
Done after hirschberg to find the magnitude of axes deviation
How is Krimsky done
Place prism over the eye that fixates
What corrects Eso?
What corrects Exo?
Eso: BO
Exo: BI
REMEMBER: BORE BIRX
What is recorded fro Krimsky
Eye
Magnitude (1 mm; 22 prism diopter)
Direction
What is Buckner test purpose?
To evaluate the symmetry of binocular fixation
Great for infants and young proverbal children
how is Bruckner test done
Have patient look at ophthalmoscope
Look at the red reflex
Bruckner test is done
Results: equally bright
Binocular fixation
Hirschberg: there is a deviation
Bruckner: the eyes are no equal reflex
Dim eye:
Brighter eye:
Dim eye: fixating
Bright: non-fixating eye
Hirschberg: normal
Bruckner: not equal
Dimmer eye:
Brighter eye:
Dimmer: media opacity
Brighter: retinoblastoma
You perform Bruckner and see a crest towards the head of the ophthalmoscope
Hyperopia
You perform Bruckner test and there is a crest toward the handle of the ophthalmoscope
Myopia
What are the 2 types of Torsion
Cycloversion
Cyclovergences
Cycloversions are
Conjugate movements
What are cyclovergences
Dis-conjugate movements
What is the purpose of double Maddox rod
To detect torsional misalignment and cyclodeviation
What is the downside of double Maddox rod
It does not differentiate between phoria and tropia
In NSUCO to test saccades you would
Have them look back and forth between red and white bead
How many cycles are tested for NSUCO saccades
5
How do you test pursuits in NSUCO
Have patient follow bead 2 cycles clockwise, 2 counterclockwise
How many cycles are tested in pursuits for NSUCO
2
And 2
What do you observe in NSUCO
Eye movement
Head movement
Body movement
How do you score NSUCO
Ability
Accuracy
Head movement
Body movement
What is the best score in any category for NSUCO
5
What is the purpose of the developmental eye movement test
Visual verbal ocular motor assessment
Accounts for difficulties in naming numbers
Check vision therapy progress
How is DEM tested
Pt calls off a series of numbers quickly
You compare the response times
And numbers of errors
Should you administer DEM if the child fails the pre-test (cant read off numbers in 12 seconds)
NO
DEM subtlest A and B tests
Vertical saccades
40 #s
Record time it took
DEM subtest C tests
Horizontal saccades
80 #s
Record time it took
DEM substitution
Cross out number if error made, unless there was an immediate correction
DEM test transposition
Place an arrow where # read out in sequence
DEM omission
Circle is number was omitted
DEM additions
+ when extra number has been added or repeated
DEM type 1
Average performance
DEM type 2
High horizontal time, normal vertical time
Oculomotor dysfunction
DEM type 3
High horizontal and vertical times
Normal ratio
Difficult in automaticity of number naming
DEM type 4
All normal
Deficit in oculomotor skills and automaticity
Combo of 2 and 3
What is the purpose of King-Devick test:
Verbal visual ocular motor assessment
Rapid number naming
Tests saccadic eye movements
Concussion detection
Assess neurological fxn
What is Hartman distance
Elbow to middle knuckle
How is King-Devick done
Patent calls off a series of numbers as quickly as possible
Compare to expected values
If test card 1 takes longer than 50 seconds do you move on to the next card?
NO
If the total time for card 1 and 2 is greater than 100 secs should you stop at card 2?
YES
If the pt is younger than 10 y.o. And cannot complete card 3 how do you score them?
Sum of test cards 1,2 and errors
T/F you do not count the error in King Devick if the pt quickly corrects it
True
What is the purpose of Groffman tracings
Oculomotor assessment
Reading ability tested
Little cognitive ability
How is Groffman tracing test done
You have pt card
Harmon distance
Have them trace the line at A with ONLY their eyes, tell what number is at the end
Repeat for D
Do 5 more tracings
How do you score Groffman tracing
Incorrect number: 0
Correct number/used finger: 0
Correct number: score scale
Add scores together
Compare to normative data
How is Double Maddox rod tested?
Trial frames
OD red
OS: white
Lenses placed vertical
Make lines parallel
Right the angle that line must by rotated
Double Maddox rod: the red line tilts toward the nose
Eye is excyclodeviated
R SO underacting
What does the amblyoscope test
Obj/subj Angle of deviation
Cyclophoria, hyperphoria
Hor/vert vergences
In amblyoscpe the fixating eye sees the more detailed image? T/F
True
What does Parks 3 step look for
Muscle responsible for deviation
What are the 3 steps for Parks 3 step
- Which eye is hyper in primary
- Does it increase on R/L gaze?
- Does it increase on R/L head tilt
T/F the paretic muscle is the muscle circled 3 times on parks 3 step
True
How is Forced duction done?
Anesthesia
Pt looks toward limited gaze
Grab conj opposite dxn you are moving
Move eye toward limited gaze
If the eye moves in forced duction what does that tell you?
Paretic muscle
- forced duction
I’d the eye does not moved in forced duction what does that tell you?
Mechanical restriction
+ forced duction
How is Hess Lancaster test done
- Pt wears R/G glasses
- Gives the patient light wand
- on target tester hold their light at a point
- pt tries to match it with their light
- mark this on form
If the pt has green light
Tester has red light
Hess Lancaster
What eye are you testing??
Left eye
If the pt has the red light
Tester has the green light
Hess Lancaster
What eye are you testing?
Right eye
Hess Lancaster The eye with the smaller field is_______
Affected eye
Underaction
The eye with the greatest underaction is the affected muscle
Hess Lancaster larger field ______
Unaffected eye
Muscle with greatest overaction: contralateral synergist
2nd greatest overaction: ipsilateral antagonist
In Hess Lancaster if you have differing sized fields what does this tell you
Recent condition
In Hess lancaster if you have similar sized fields what does this tell you
Long standing condition
What is Hess Lancaster comitancy
Deviation is the same in all positions of gaze
In Hess lancaster what can a mechanical restriction be seen as
Narrow fields in opposing directions
A/V patterns can occur n HEss Lancaster
Yes
What is the most common sign of a neuromuscular problem
Dilation of visual axes (tropia/phoria)
What is required for proper alignment
Good sensory and motor function
What can abnormalities with sensory function cause?
Disruption in motor fusion
Deviation
What is a phoria?
Latent tendency for the eyes to deviate when fusion is broken
What is fusion needed for
Binocular vision
Prevent diplopia and suppression
What can break fusion
Alternating CT
Fatigue
Illness
Stress
What is a tropia
Manifest deviation of the eyes
When is tropia seen
Unilateral cover test
What does tropia cause?
Amblyopia
Diplopia
Suppression
What is a unilateral tropia
Patient fixates with other eye
What is a constant tropia
Fusion is inadequate to keep aligned
What is intermittent tropia
Fusion functions at some times, but not all times
Patients can have tropia or phoria both at different distances
True
To correct Exo
BI
To correct Eso
BO
You correct Hypo
BU
To correct Hyper
BD
T/F if both eyes have BU or BD and the value isn’t split what can it cause
A version
Why is the vertical prism split
You treat with the net binocular effect
BUT you DO have to keep the same base OU
What happens if BO and BI are given
Version created
Will not correct the deviation because they are yoked prisms
Effect will be cancelled out
What is torticollis
Abnormal head posture
Can been alone or in combination
Prolonged can cause permanent facial asymmetry and contracture of neck muscles
What is ocular torticollis
A compensatory response to an ocular problem
Attempts to maintain bonocularity, VA, or limited VF
What are some abnormalities that can cause ocular torticollis
Nystagmus Paretic strabismus Restrictive strabismus Supranuclear disorders A/V patterns Monocular blindess Ptosis Refractive error VF defect
What is comitancy
Deviations are comitant or non-comitant
Deviation size remains the same in all positions of gaze
Non-comitant:
deviation size is different in different positions of gaze
How do you determine comitancy
CT in all gazes
What can cause non-comitant
Innervation problems or mechanical restrictions
What do vergences play a role in
Neuromuscular anomalies
What are some sites of lesions
Supranuclear
Nuclear
Infrnuclear
Myogenic
What else can cause strabismus
Anomalies of the face or orbit
Hydrocephalus, craniosynostosis, cranial conditions
Congenital:
Onset at birth or during first 6 months of life
Acquired:
Any strabismus that developed after 6 months
Paralysis
Action o muscle or group of muscles completely eliminated
Paresis
Action of muscle or muscels is impaired
Palsy
General term for paralysis or paresis
When do paralysis, paresis, and palsy cause?
Non-comitat deviation because of over or under action of involved muscles
If there is difficulty moving the eye is a certain direction what should you consider?
Mechanical restriction
What can cause fusion disruption by sensory impairment
Trauma
Disease
What can cause mechanical restrictions
Agenesis Abnormal insertion of EOM Abnormal adhesions at tissue Fibrosis of muscles Tumor Sarcoidosis
What can uncorrected refractive error cause?
Esophoria
What does vestibular abnormalities cause
VOR
T/F a patient may have a small phoria, but no symptoms because the sensorimotor system is able to cope with the deviation
True
What are vertical deviations likely to cause symptoms
Vertical fusional amplitudes are naturally limited
What can poor fusion be associated with
Fatigue Asthenopia HA avoidance Diplopia Suppression
Is infant ocular instability normal?
When should you be concerned?
Yes
If it persists and is constant and large
What is an ESP phoria
Latent esodeviation controlled by fusional vergences so the eyes are aligned in binocular conditions with fusion
What is an esotropia
A manifest deviation that is not controlled by fusional vergences
What can cause an esodeviation
Innervation Anatomical Mechanical Refractive Accommodative Genetic
What do fusional vergences allow
Fusion and alignment
What is pseudoesotropia
Appearance of ET when eyes are actually straight
HB and CT will be normal
Seen in children with wide, flat nose bridges and prominent epicanthal folds
What is infantile ET
Onset is between birth and 6 months
Large constant ET
Family history?
What do most children with infantile ET also have?
Neurological or developmental conditions
Cerebral palsy, hydrocephalus, prematurity
What is cross fixation in relation to infantile ET
Using the adducted eye to look in to the contralateral view
What can develop from a constantly deviate eye
Amblyopia
Low hypertrophic
What can develop from infantile ET
Amblyopia AV pattern DVD Over action of IO Nystagmus AHP
What can you do to manage strabismus
Correction of refractive error
Add power Prism Occlusion- amblyopia treatment Vision therapy Botox? Surgery (large angles) Full cycloplegic refraction Comprehensive exam
What is accommodative esotropia
Deviation associated with accommodative reflex
6mon-7yrs (avg: 2.5 yrs.)
It starts intermittently and can become constant
What can cause accommodative esotropia
Hereditary
Trauma
What can be present with accommodative ET
Amblyopia
Diplopia (active suppression)
What are the types of accommodative esotropia
3
Refractive
Non-refractive
Mixed
____% of all esotropia have an accommodative component
50%
What is refractive accommodative ET due to
High hyperopia (forces pt to accommodate) Insufficient fusional vergences to diverge
What is non-refractive accommodative ET due to
High AC/A
Increase in accommodation at near drives convergence but there is insufficient vergence to diverge
What is mixed accommodative ET due to
High hyperopia
High AC/C
What does refractive accommodative ET lead to
Accommodative convergence
Pt doesn’t have enough fusional divergence to counter the increased convergence
What is the average hyperopia that can cause refractive accommodative ET
+4.00
+3.00-+6.00
What can occur is hyperopia is higher than +6.00D
Isometropic amblyopia
Patient has too much blur and will not be able to accommodate
How would you manage refractive accommodative ET
Comprehensive exam
Cycloplegic refraction
Full hyperopic correction for full time wear, can reduce plus later
Start amblyopia treatment if VA doesn’t improve with Rx
What is ET greater at near in non-refractive accommodative ET
Because of the need to accommodate at near
What is accommodative convergence/accommodation ratio (AC/A)
Amount of convergence induced by a change in accommodation, can be accompanied by a change in vergence
What do accommodation and vergences allow for
Clear, stable single binocular vision across a range of viewing distances
What does AC/A help evaluate
The strength between the accommodative and vergence systems
When are abnormal AC/A ratios seen
In binocular problems
How do you calculate AC/A ratio
AC/A: absolute change/(absolute change in accommodation)
How do you manage non-refractive accommodative ET
-Treat refractive error
-Bifocals (segheight bisect pupil) to reduce accommodation and accommodation convergence
- cyclo exam yearly
No surgery
How do you mange mixed accommodative ET
Full hyperopic correction
Bifocal (based on AC/A)
NO surgery
What is partially accommodative ET
Accommodative contributes to but does not account for the entire deviation
There is a reduction in the angle (residual ET remains after treatment)
Constant unilateral
What is common in partial accommodative ET
Suppression
ARC
What is early onset non-accommodative Esotropia
Similar to infantile ET, onset is later (6mo-2yrs)
ET same at D and N, comitant
No accommodative component
Insignificant amount of hyperopia
How do you manage early onset non-accommodative ET
Correct refractive error (prisms, bifocals)
Amblyopia treatment
Vision therapy
Surgery
Neuro causes
What is acute acquired ET
Comitant
3-5 yrs
Unilateral, constant
What can cause acute acquired ET
Illness, stress, aging
How do you manage acute acquired ET
NEURO eval ASAP
Correction
Prism/surgery
Amblyopia treatment if needed
What is sensory ET
ET that develops due to vision loss in one eye
Prevents clear, focused retinal images
Prevents symmetrical visual stimulation OU
Poor VA
Constant unilateral deviation
Poor cosmesis
What can decreased vision loss n sensory ET be due to
Congenital cataract Corneal scarring Optic atrophy Prolonged blur Retinal/macular disease Anisometropia amblyopia Ptosis PHPV
How do you manage sensory ET
Eliminate Pathology in critical period
Polycarbonate lenses for full time wear
Treat secondary amblyopia
Surgery can used for residual deviation
What is divergence insufficient ET
Non accommodative
Greater at distance then near
Comitant Adults Decreases fusional divergence at D Diplopia at D HA
Refractive error present
No sensory adaptations
How do you manage divergence insufficiency ET
NEURO REFERRAL
Through evaluation (trauma, elevated ICP)
Correct error BO for diplopia at D VT Botox No surgery
What is consecutive ET
After exo strabismus surgery
Could be symptomatic
Amblyopia can develop
Magnitude varies
Unilateral or alternating
Spontaneous improvement can occur
Treat error
Try BO prism or plus lenses
Repeat surgery for very large derivations
What is non comitant esodeviation
6th nerve palsy
Duane’s syndrome
What is an XP
Latent exodeviation controlled by fusional vergences
Treatment is needed if there is asthenopia or diplopia
What is XT
Manifest deviation
T/F exodeviations can vary among ethnic groups
True
What is pseudoXT
There is proper alignment but postive angle kappa
Wide interpupillary distance makes it look like there is exodeviation
What is divergence excess type XT
In childhood
Larger at D
What is basic XT
In adults
XT same at D and N
What is convergence insufficent XT
In adults
larger at near
What is the most common XT
Intermittent
What is intermittent XT
Deviation is latent at times and then it becomes manifest
Before 5 yoa
When is intermittent XT manifest
During visual in attention Fatigue Stress Fusional factors are not active Later in the day Day dreaming
What effect can bright light have on intermittent XT
Reflex closure of one eye
What can intermittent XT be associated with
Small hypers
A/V patterns
What can untreated intermittent XT lead to
Constant XT
Reduced stereo
Amblyopia (no common unless constant in early life)
How do you evaluation intermittent XT
Comprehensive history (age of onset, frequency)
CT at D and N
Control assessment
Sensory test
What is good control of IXT
XT only manifest on CT
Resumes fusion rapidly
What is fair control of IXT
XT on CT, fusion regained after blinking or refixating
What is poor IXT
XT manifest spontaneously nad for an attended period of time
Slide 40
How do you manage IXT
Correct significant error, mild myopia, moderate (greater than +4) hyperopia
Correcting mild hyperopia can make deviation WORSE Patching for amblyopia VT (fusional vergence training) Prisms Surgery Botox
What is convergence insufficient XT
XT greater at N than D Intermittent alternating at N Low AC/A Poor near fusion convergence Receded NPC
What are some symptoms of convergence insuffiency XT
Asthenopia
Diplopia
Blurred near vision
Common during reading
What is a treatment option for convergence insufficiency XT
Vision therapy
BI reading glasses
What is constant XT
Commonly seen in older patients with sensory XT or patients with longstanding XT that has decompensated
Enlarged VF
Surgery could be used
What is infatnile XT
Large, constant angle Could alternate Less common than infantile ET Present before 6 mo of age Likely to have neurological issues or craniofacial disorders
Poor adduction on version
How would you treat infantile XT
Neuro consult
Treat refractive error
Treat amblyopia
Surgery in children
What is sensory XT
Any condition that causes vision loss in one eye
What are some symptoms of sensory XT
Poor VA
Poor cosmesis
Constant or unilateral
Large angle
What should you determine in sensory XT
If VA can be improved since this may improve alignment with peripheral fusion
If VA is improved, surgery can be useful
If VA does not improve, misalignment could occur again after surgery
What is constructive XT
Common post surgery
Months-years after surgery
