Investigation and management of anomalies of convergence and accommodation - Miriam Flashcards
what are the different convergence anomalies? (4)
- convergence insufficiency
- convergence fatigue
- convergence paralysis
- convergence accommodative/spam
what is convergence insufficiency?
inability to obtain adequate binocular convergence without undue effort
what is convergence fatigue?
inability to maintain convergence over time
is convergence insufficiency primary or secondary?
may be both
is primary CI treatable?
yes
what risk factors for convergence insufficiency?
there are LOTS
- illness
- fatigue
- anti-depressants
- pregnancy
- students with exam stress
- change of jobs (lots of microscope work)
- computers
- constant distance vision
causes of a secondary cI?
- convergence weakness XOP
- uncorrected refractive errors
- accommodative insufficiency
- latrogenic weakened medial recti (treated SOT)
-PARKINSONS* - THYROID EYE DISEASE*
- INTER NUCLEAR OPHTHALMOPLEGIA*
*REFER
which BV test is best to use to see if there is a sinister cause for a finding?
ocular motility
symptoms of CI
- HAs
- eye strain
- difficulty changing focus
- asthenopia
- blurred vision (decomp. XOP)
- diplopia (XOT)
- convergence fatigue
cover test results for CI
XOP/XOT @ near
ortho @ dist
RAF rule results for CI
reduced or poorly maintained near point
how many times do you do RAF ?
3x
what happens to the near point if there is convergence fatigue on the 2nd or 3rd attempt of RAF?
near point reduction
how do you SUBJECTIVELY test for CI
- When patient reports diplopia
- Remember that the target will be blurred (test does NOT examine accommodation)
how do you OBJECTIVELY test for CI?
- watch the px’s eyes split
- note which eye diverges first, distance and if they could maintain convergence
- note if dip was noticed
do you use the px’s glasses when testing for CI?
if they need them to look at near - YES
explain jump convergence:
- hold 2 objects in front of px at different distances
- ## ask px to look from distance to neear object, bringing the near object closer each time
when carrying out prism fusion range in someone who has a convergence insufficiency, which result will be reduced?
base out at near
what does it mean is fusional reserves are oly abnormal on RAF rule?
children can occaisionally let their eye go on RAF rule
what do you do if you child let’s their eye go out on RAF rule?
put budgie stick close to their eyes and see if they converge
If they hold it for a long time - good fusional reserves `
how do you asess the near point?
RAF rule in dioptres
if accommodation is normal monocularly but not binocularly, what does this mean?
blur is not caused by lack of accommodation but lack of convergence
how do you measure a deviation?
prism cover test
what is reduced with accommodation insufficiency?
visual acuity
if a px has a latent or manifest deviation, what is reduced?
stereoacuity
what do you do if you see an incomitancy on ocular motility?
REFER
how do you manage a convergence insufficiency?
- treat any pathology
- significant refractive error corrected
- exercises
which orthoptic exercise is the first line of treatment for CI?
dot card
how do you use a dot card
place card at the end of the nose, line will appear double due to physical diplopia, ask px to keep each dot as single starting with the dot furthest away
name the exercises for CI
- binocuary convergence with a pen
- using a lollipop stick with letters
- jump convergence
- BO fusion range
- voluntary convergence
- stereograms
how do you use stereograms
- 2 similar pictures with some differing characteristics
- hold card at 33cm
- px stares at near object in front of the card
- position of the target is then changed until 3 figures are seen
how long should the px use exercises per day?
1-2 mins 3x a day
what must you do after doing exercises?
relax your eyes by either looking in the distance or closing your eyes
why must you close your eyes or look in distance after doing exercises?
reduces risk of convergence spasm
how do you treat secondary CI?
address the primary condition
what is convergence paralysis?
the ability to converge closer than infinity is entirely lost
what causes convergence paralysis?
primary
secondary to
- closed head injury
- viral illness
- occlusive vascular disease
- encephalitis feature of parinaud’s`
if someone has sudden onset of convergence paralysis what do you do?
REFERRRRRR
what are the signs of convergence paralysis?
nil convergence
XOT
crossed diplopia
blurred near VA if accomm affected
pupillary response may be absent for convergence but present for light
normal ocular movements
absent positive fusion range (BO)
management for convergence paralysis?
urgent referral
occlusion/patching
botox
BI prisms to correct XOT
Near ADD if accommodative insufficiency
adapt to symptoms
which muscle is contracted in a convergence spasm?
medial rectus
which muscle is contracted in accommodative spasm
ciliary muscle
if you get convergence spasm, what else will you get?
pupil miosis
aetiology of convergence/accommodative spasm?
- over treatment of CI
- uncorrected hypermetropia
- intermittent distance XOT
- organic - drugs, inflammation, alcohol, problems within the brain
- non-organic - psychological
signs and symptoms of convergence/accommodative spasm
- SOT
- SOT > distance and lateral positions of gaze
- blurred vision in the distance
- mactopsia
- constricted pupils
- pseudomyopia
- headache
- lead on dynamic ret
what is pseudomyopia?
too much accommodation and rays of light fall in front of the retina
what is the differential diagnosis for convergence/accommodative spasm?
6th nerve palsy
- normal pupils
- normal VA
- abnormal dolls head
management of convergence/accommodative spasm
- treat pathology
- cyclo or atropine refraction to elicit full hypermetropic Rx
- any hypermetropic refractive error corrected
- atropine intillation
- patching
- botox
- psychiatric counselling
- improving nergative fusion amplitude
name 3 accommodative disorders
- accommodative insufficiency/fatigue
- accommodative paralysis
- accommodative inertia
aetiology of accommodative insufficiency/fatigue
- high hyperopia
- children with down’s syndrome
- illness (infection, glandular fever)
- drugs (hypertensive and antidepressats)
- trauma
signs/symptoms of accommodative insufficiency/fatigue
- blurred vision @ near
- asthenopia
- micropsia
- remote NP association for age
- can develop SOP bc effort to accommodate
- lag on dynamic ret
assessment of accommodative facility
flipper lenses
what is the normal number of cycles for a young adult?
10 cycles of +/- 2.00
clinical signs of accommodative fatigue
- unable to maintain NP of accommodation 3x
- reduced accommodative facility
- dynamic retinoscopy normal to begin with then a lag
- distance vision normal, near vision initially normal but then reduces over time
- CT reveals SOP for near over time
management of accommodative insufficiency/fatigue
- treat any pathology (do fundus exam)
- cyclo refraction
-correct any RE even hypermetropia - exercises
- down’s syndrome
- extra convex lenses for reading (CRUTCH)
name 2 exercises for accommodative insufficiency/fatigue
- lend flippers and increase the number of rotations and power
- accommodative push ups - with letters on lollipop sticks mono and bioc
aetiology of accommodative paralysis
- associated with convergence paralysis
- drugs (cycloplegia in the conjunctival sac)
- psychosomatic
- neurological (diptheria, parinauds, total 3rd nerve palsy)
- trauma (blunt causing paralysis of ciliary muscle, closed head injuiries, whiplash)
how do you manage accommodative paralysis
refer urgently if recent onset
treat pathology
aetiology identified and treated
refraction in children
in unilateral paralysis attempt to match the near points of the 2 eyes by use of multifocal reading ADD
is accommodative paralysis easy to treat?
no
what happens in accommodative inertia
- difficulty changing focus
- difficult relaxing and exerting accommodation
- occurs in both eyes
aetiology of accommodative inertia
associated with presbyopia
cataract
symptoms of accommodative inertia
- blurred vision when changing focus
- distance and near vision - both reduced until significant time has passed
- take lots of time to investigate near point of accommodation
management of accommodative inertia
- treat pathology (fundus exam)
- correct even minimal hypermetropic correction
- bifocal reading ADD of +1.00D
- orthoptic exercises
which orthoptic exercises would help eith accommodative inertia
accomodative flippers
push up accommodation
jump accommodation
how do you measure accommodative facility? (4)
- RAF rule
- Dynamic ret
- flipper lenses
- cover test
