Unit 2/3 Flashcards
Most common working distance for Ret
Arms length (2/3m or 66.7cm)
Three movements with retinoscope
-Against movement (minus lenses are added)
-With movement (plus lenses are added)
-The whole pupil glows (neutralised)
When you are working at 66cm what WD power would you add?
+1.50
When you are working at 50cm what WD would you add?
+2.00
3 phases of retinscope
- Initial lens selection
- Identification of the principal meridians
3.Neutralisation of the refractive error along the two principal meridians
what does BVS stand for?
Best vision sphere
When neutraising the meridians
- Neutralise the more positive “MOST WITH” (or least negative/least against) meridian first
-Use 0.50D intervals until the first meridian is neutralised - Neutralise the remaining AGAINST movement with a concave cylinder lens - lines orientated in the directin of this meridian
Purpose of doing needs assesment
- Figure out why the px has come to office
- Develop a database of info (ocular and health)
- Develop rapport (relationship)
FOLDAARS
F- Frequency
O- Onset
L- Location
D- Description
A- Associated symptoms
A- Aggravating factors
R- Relief
S- Severity
What type of questions should you avoid with pxs?
Leading questions
ex. “Your eyes dont get fatigued , do they?”
When to inform patient expectations
Cataracts
Cataract surgery
Macular degeneration
Retinal disease
Corneal disease
Amblyopia
High rx errors
Manangment of px expectations can be broken down into 5 steps
- Communication
- Fidelity / Honesty
- Broker (negotiate)
- Consensus
- Documentation
Communication - px expectations
-Really listen to what patients are stating
-Listening to what the px wants is crucial, this is the foundation for making any other treatment recomendations
Fidelity - px expec
-pxs eyes may be limiting factors for their visual aspirations
-time should be spent explaining why a procedure or lens is not a good idea so that the px can fully appreciate their own reality
Broker - px exp
-Negotiate refractive distances and lens options to best accomodate pxs needs
-Pxs need to know where they gain and where they give up something
Consensus - px exp
Agreement about how to proceed
Explain the course of action to pxs and then have them repeat back in their own words
Documentation - px exp
-brochures that lightlight risks and benefits should be the last thing pxs have in hand when they leave office
when to refer (RX..)
When there is a large change in RX
-exceeding +/- 1.00 in the last 6 months
-exceeding
+/- 2.00 since the most recent RX
When to refer (other parameteres)
Large changes in keratometry, IOP, VA and visiual field
When to refer (va)
-best corrected visual acuituy will be less than 20/25 in either eye
-Not satisfied with the best corrected vision after 2 independed refraction have been conducted
Would you refer a px if their best corrected visual acuity is OD: 20/30 and OS: 20/40 after your refraction?
Yes, it is less than 20/25
Two types of dominance tests
Sighting dominance
Sensory dominance
What is sighting dominance
Hole in the card, or hands form a triangle
-Test is carried out with the px fully corrected for distance
Monovision eye dominancy
‘Near point add’ is provided in the non-dominant eye
What is sensory dominance
“Fog method”
-Test is carried out with the px fully corrected for distance
-Px is asking to observe a distance target binoculary
-A +2.00 DS trial lens is held in front of each eye in turn
-Whatever eye the is more blurry with a +2.00 is your dominant eye
Can you predict a reading add based on age?
Yes you can - age is relevant to presbyopia
Can we predict changes in RX
Yes we can predict the amount of RX change by drop in VA
-ex. Degradatiom of 1 line of vision corresponds to approximately -0.25 but also depends on pupil size and blur tolerance
If VA drops 4 lines how much RX change is there ?
-1.00 because each line is considered -0.25
Objective refraction
Does not requrie pxs co-operation, will not need feedback from px
When is objective refraction appropriate
-Noticeably significant VA change
-Language/verbal barriers
-Pediatrics
Prescription benchmarking
More appropriate for cases where
-Minimal rx change is expected
-Benchmark vision is 20/20
Would you refer if you find a shift of -1.50D when comparing pxs RX from 6 months ago?
Yes you would refer because it is exceeding +/- 1
