Week 1.11 Management Options Flashcards
At what angle of deviation, suggests what treatments
> 20PD - surgery
15-20 - other factors must be favourable for orthoptics
<15 - orthoptics?
<6 - microtropia, no orthoptics
What are the different types of optical management methods?
Refractive error
Refractive modification (extra+/-spheres)
Prisms
What are orthotic exercises examples?
- ramp vs step
- Vergence in sync with accommodation or extend ability to dissociate from accommodation
Pharmacological management method
Surgical
How does ramp Vs step exercises work?
Ramp is pen to nose - constant change
Step is jump convergence - looking at pen then distance
What is the purpose of orthotic exercise exercises?
- overcoming suppression
- Control an intermittent deviation.
- Extend fusional amplitudes
- Improve relative (fusional) convergence
- Improve NPC
Suppression: bar reading
Need to be able to identify 2PX they’re seeing a different image out of one eye compared to the other
Must be done when eyes are not strabismic
Read sample of text with the finger in front .
Should still be able to read it
If close one eye finger is covering some of words, but with both eyes open, you can read .
Suppression: red filter method
- Red filter before dominant eye
- Trace a picture with red pen
- Drawing is seen by poor eye but paper by both eyes
- Or sort coloured beads - must be using suppressing eye as red filter distorts the colour
What are some examples of ramp vs step exercises
Pen to nose
Dot card
Brock string
How to do pen to nose exercise
Move pen close to nose tell me when it goes double
Hold it and trey to keep it single
Move back few cms goes single again
Move back in try to make it single
problem with this is px doesn’t see double and goes straight to the nose if they’re only using one eye. So one way to improve is by using a second pen as the supression check. So the pen that is further away is the supression check, they look at the front one moving towards them making sure they’ve still got two of the pens further away. If the pen further away goes one that’s when they know the eyes wandered off.
How to do dot card exercise
Line of dots on a4 paper
Px starts looking at far dot - make sure they got cross in the line
Then look at next dot
Brock string
Piece of string with beads on it and this loop tie on a door handle and you could stand at other side of the room
Move beads closer towards you and string appear to cross
What’s the formula for AC/A ratio
PD + (N-D)/ A
Muscle performance can be trained to…
Extend vergence amplitudes
Increase relative fusional convergence
How to extend fusional vergence amplitudes
Prism bar - keep doing it again and again until their limit increases bit by bit
Base out - increase prism until convergence fails
Encourage to make single
Aim for 40-46 at near and 20-25 at distance or enough to satisfy sheards criterion
Base in - harder to do, need to demonstrate improvement from baseline
Relative fusional convergence: free space technique
Involve fusion of two stereo pairs by over converging or under converging
3 cats
2 cats shown and px has to over converge to see three cats and hold for 10s move the cats away look at window and do it again
