Amblyopia 3 Flashcards
Amblyopia is a diagnosis of _________
Exclusion
What are examples of some things that cause reduced VA in one eye but are not amblyopia
- corneal dystrophy
- macula schisis
- retinitis pigmentosa
What kind of detailed history should you obtain for someone that you think has amblyopia
- probing birth history (prematurity and low birth weight)
- family history of amblyopia
- history of patching or eye drops
What is the very first thing you want to test on a patient in an eye exam?
Visual acuity
What does the exam overview look like for someone suspected of having amblyopia
- detailed history
- VA
- Cover test
- ocular motility
- pupils
- accommodation
- binocular function (stereo, W4D, fixation)
- cycloplegic refraction
- anterior and posterior segment eval
Why do you want to do a cycloplegic refraction?
Completely knock out accommodation so you can get the best refractive error. Gives true picture
Why do you want to check the anterior and posterior segments on someone suspected of having amblyopia
Rule out disease
Why do you want to check pupils on someone suspected of having amblyopia
Make sure there is nothing wrong with ONH, sensory input
Amblyopia treatments
- optical treatment
- occlusion therapy
- vision therapy
What is the first step in the management plan for a patient with amblyopia or strabismus
Determination of refractive error
Retinoscopy on a deviated eye
May not yield the correct amount of refractive error because the retinoscopy is done off axis. Cover the good eye to have the off axis eye swing back onto axis
What is the method of choice to determine the refractive error in children?
Cycloplegic refraction
How is optical correction done?
Glasses or contact lenses
What is the difference between the two eyes that is a point of concern in someone who is anisometropic hyperope
Difference of 1.00D or more
What is the difference between the two eyes that is a point of concern for someone who is anisometropic myope
More than 3.00D
What is the difference in eyes that is a point of concern for someone who is an anisometropic astigmat
More than 1.5D
When does it become likely that a hyperope with be isoametropic
Greater than +5.00D
At what prescription is it likely that an astigmat will be isoametropic
More than 2.50D
When is it likely that a myope will be isoametropic
More than 6.00D
How does amblyopia affect the subjective refraction
The visual system is not able to respond well during the subjective refraction. The amblyopic eye is insensitive to the small changes to discriminate during subjective refraction
What helps give the best objective measurement of the refractive error present?
Completely relaxing accommodation, usually with an anti-muscarinic such as cyclopentolate
What is a tough question even for the most seasoned eye care professionals?
How much prescription they should give
How should prescribing practices be done?
Based on the case you are treating
After the retinoscopy and subjective refraction, the prescription to issue is based on the ________ and ___________
- findings
- other relevant information
Things to think about when prescribing glasses for kids
- is refractive error still changing
- is there accommodative strabismus that has developed
- will full Rx interfere with emmetropization
- will full correction give been better acuity than partial correction
- is this child still in critical period
- how early do i treat this child
- what is prognosis
- what is the treatment goal for the child
What is the goal for optical treatment
- clear retinal image for each eye to allow for binocularity
- stopping any amblyogenic process
Accommodative ET sc in vision therapy
This is dumb because they should be corrected before they ever have to consider vision therapy
Start with ______first before introducing other management for amblyopia
Prescription
Why do we start with prescription first before introducing other management for amblyopia?
- allows child to adapt to the prescription
- allows you to determine the amount of clarity that is gained by correction only
- allows you to see how aggressive you may have to be
- improves compliance and the acceptance of subsequent management that may be introduce
- f/u could be 3-4 months, depending on case
If hyperopic anisometropic amblyopia is present without esotropia, what can be prescribed?
A partial balanced prescription can be issued
If an accommodative esotropia is present, what needs to be prescribed?
Close to the full prescription should be considered
What is he goal when prescribing?
Balance between the two eyes and alignment
Occlusion therapy
Concluding the better seeing eye to stimulate the amblyopic eye and force it to improve visual function
-also eliminates eccentric fixation
What types of occlusions are there?
- direct (over better seeing eye or alternating)
- full time or part time
- with occluded or by penalization
Penalization
A form of occlusion where atropine is used to blur the vision in the better seeing eye
Barriers and concerns about occlusion therapy
- compliance
- development of strabismus
- occlusion amblyopia (will happen to better seeing eye if it is patched too much)
- cosmesis
- skin irritation
- atropine side effects
Atropine side effects
- hot as a hare
- dry as a bone
- blind as a bat
- red as a beet
- mad as a hatter
Vision therapy
- visual tasks and procedures to improve vision
- improves visual efficiency (eye movement, accommodation, and binocularity)
- does not replace optical correction, it augments it
Case considerations and trends of deprivation amblyopia
- remove any obstructions to minimize binocular disruption
- refractive error corrected for best vision
- amblyopia treatment initiated after reevaluation
Case considerations and trends for isoametropic amblyopia
- correction as soon as possible
- reevaluate after 4 months
- amblyopia treatment initiated
- VT
Case considerations and trends for anisometropic amblyopia
- correction
- reevaluate 4 moths
- amblyopia treatment
- VT
Case considerations and trends for strabismic amblyopia
- correction
- reevaluate VA and bino
- amblyopia treatment
- VT
- prism
- surgery
When is surgery contraindicated when there is a strabismic amblyopia?
Contraindicated in most accommodative esotropia
