6 - Cycloplegics Flashcards
why do we use cycloplegics
- assessment of refrative error
latent hyperopia
- penalisation
- adaptation to specs
- anterior uveitis - dilating pupil + alleviating ciliary spasm
- corneal abrasion ^
what are the optometric indications from history &symptoms
- asthenopia
- reading difficulties
- manifest deviation
- FH of refractive error at early age
what are the optometric indications from clinical tests
** bv anomaly**
* manifest eso
* sometiems latent deviation
** fluctuating ret pic**
- large diff beween subjective and objective
- poor fixation
VA reduced
what are the ideal properties of a cycloplegic
- rapid onset
- adequate depth + duration
- no stinging
- no mydriasis
- no toxic effects
- local
- systemic
what are the effects of cycloplegics
- initilally mydriasis
- as iris located anteriorly to ciliary muscle (unnecessary side effect) - cycloplegia
- paralysis of the ciliary muscle, resulting in loss of accommodation. due to paralysis, curvture of lens can no longer be adjusted to focus on near - reduced tear secretion
what do anti muscarinic agents affect
- lacrimal gland
- iris sphincter muscle
- ciliary body
what advice should you give before instillation
explain need ot use, onset, duration, expected side effects, caution
if consent is denied?
parent
- explain adv and disadv
- note refusal on record
- if concern for child great, refer to GP
child
- gillick competent: can child agree themselves
- record all discussions
checking for cycloplegia
- measure accommodaton
- check ret reflex
does mydriasis indicate that cycloplegia has been achieved
no
Cycloplegic ret
- sit child on parent knee
- ask px to fixate upon light
- no need to fog other eye
- observe central movement, ignore periphery
abberations higher due to larger pupil
tropicamide is the weakest or stongest?
weakest. only effective in adults
1%, used as mydriatic
most commonly used cycloplegic
cyclopentolate 0.5% and 1%
what is atropine sulphate
- toxic agent
- POM
- used by IP
what are the preparations of atropine
- AS eye drops 0.5% and 1%
- AS eye ointment; 1%
- minims: 1% (bausch&lomb)
store below 25 and protect from light
what are the doses for atropine in adults and children >3months
1) eye drops
- one drop (1%) twice per day for 1-3 days before refraction
2) ointment
- two times a day 1-3 days before refraction
atropine- timing
what is the atropine tonus allowance
- allowance needs to be made for dependant tone
- spherical adjusted in LESS positive direction
- -1.00DS for low myopes annd hyperopes
- 0.00DS for moderate and high myopes
what are the contraindications of atropine
- known allergies
- narrow angles
cautions of atropine
- children <3 months
- elderly/ill
- down syndrome
- children with brain damage
- soft cl
- hyper sensitvity
-intermittent manifest deviations
atropine sulphate ocular side effects
- transient stinging
- blurring
- photophobia
- raised IOP
after repeated use
- hyperaemia
- oedema
- itching/irritation
- follicular conjunctivitis
atrophine suulphate general body side effects
- dry mouth/skin
- flushing/increased body temp
- cyclopegia
- ataxia, hallucinations, confusion, difficulty speaking
- tachycarida
death from respiratory depression (more likely in kids)
dry as a bone, red as a beetroot, blind as a bat, mad as a hatter
what are the additinal uses of atropine
to treat amblyopia
- instilled into better eye
- prevents accommodation
- used when child will not tolerate patching
- excellent resulys
cyclopentolate hcl
- commonly used cycloplegic
- synthetic drug
