Cycolplegic Flashcards
what is cycloplegia
loss of accommodative function, hence cycolpegic dilation drops
what is mydriasis
pupillary dilation
what are cycloplegic drugs
agents which block the PNS in the iris and ciliary body, results in loss of accommodation and pupillary dilation
What are the 3 most common cycloplegic in the optometric field ?
atropine
cyclopentolate (0.5% and 1.0%)
tropicamide (0.5% and 15)
what is the association of scopolamine agent
found in motion sickness medication
side effect: no accommodation
what is amplitude of accommodation
the maximum amount a pt can accommodate
what are the indications to perform cycloplegic refraction
- pt cannot fixate steadily or reduce accommodation (young child)
- ocular deviation, esotropia
- a lot more plus power ( or less minus) found in ret than subjective
- amplitude of accomm doesnt fall within normal limits of pt age group
what is pseudomyopia
the increased distance blur during evening
what is latent hyperopia
hyperope who may have masked accommodation, thus the agent will find the excess accommodation
define far point
point conjugate with the retina of the unaccommodated eye
what are the symptoms of apparent refractive origin
transient blur
occasional horizontal diplopia
headaches after near work
what are the advantages to cycloplegic refraction
- makes latent RE manifest
- allows refractive assessment w/o accommodative fluctuations
- avoids off axis ret erros
- allows dilated fundus examination
what is the significance of cycloplegic for ret
parallel with their visual axis to get a more precise finding
what are disadvantages of cycloplegic refraction
- atropine > possible systemic poisoning in young children
- mydriasis > induce angle closure > increased IOP
- increased abberations from the pupil on ret, essential to only consider central reflex
- changes of crystalline lens shape vs normal conditions, but will come back to normal state once agent wears off
- photophobia (light sensitivity), decreasing VA and near work abilities
- potential for adverse rxn (allergic rxn)
adequate cycloplegia
an amplitude of accommodation less than 2D (pt closest distance of vision = 50cm)