8 - EOMs 2
where would you look for a muscle weakness? - ANS-the position where the muscle is
maximally used
how do we test muscle weakness in ocular motility? - ANS-need to know which position
of gaze each EOM is maximally used
The further you go into this position the more subtle a weakness you can detect
what is dextroversion
- which muscles maximally used in this position? - ANS-looking to the right
- R lateral rectus + L medial rectus
what is laevoversion? - ANS-•look to the left
what is elevation? - ANS-•look up
what is depression? - ANS-look down
what is dextrodepression?
- which muscles maximally used in this position? - ANS-•Dextrodepression = down + to
the right
- R inferior rectus + L superior oblique
what is dextroelevation?
- which muscles maximally used in this position? - ANS-•look up + right
- R superior rectus + L inferior oblique
what is laevoelevation?
- what muscles maximally used in this position? - ANS-•up + left
- R inferior oblique + L superior rectus
what is laevodepression?
- what muscles maximally used in this position? - ANS-down + left
- R superior oblique + L inferior rectus
what muscles are working in primary position? - ANS-All muscles equally innervated by
a small amount
, which positions have 2 muscles being maximally used?
- why is this not a good position for detecting muscle weakness? - ANS-- elevation =
inferior obliques + superior rectus
- depression = superior oblique + inferior rectus
- we dont know which of the 2 muscles are weak
which positions are good for determining if an EOM is weak?
- what are these positions known as? - ANS-- dextroversion = R lateral rectus + L
medial rectus
- laevoversion = L lateral rectus + R medial rectus
- only 1 muscle in each eye is maximally used
- these are secondary positons
what would happen to the eye if you ask a px to look into dextroversion but their R
lateral rectus was weak? - ANS-px fails to aBduct the eye
•So the eye will be displaced inwards - the eye is esotropic compared to left one
what would happen to the eye if you ask a px to look into laevoversion but their R
medial rectus was weak? - ANS-•it fails to aDduct the eye
•So the RE would be exotropic in comparison to LE (would be more pulled out)
what are tertiary positions? - ANS-- dextroelevation + dextrodepression
- laevoelevation + laevodepression
where would we ask px to look if we wanted to investigate R inferior rectus weakness? -
ANS-dextrodepression - down + right
RADSIN
- recti ADDuct = look away from nose = to the right in RE
where would we ask px to look if we wanted to investigate a R superior oblique
weakness? - ANS-RADSIN
- recti ADDuct - so obliques - ABduct = towards nose = towards left
- superior obliques = depress eyes
- so we would ask px to look to laevodepression
where would you look for a muscle weakness? - ANS-the position where the muscle is
maximally used
how do we test muscle weakness in ocular motility? - ANS-need to know which position
of gaze each EOM is maximally used
The further you go into this position the more subtle a weakness you can detect
what is dextroversion
- which muscles maximally used in this position? - ANS-looking to the right
- R lateral rectus + L medial rectus
what is laevoversion? - ANS-•look to the left
what is elevation? - ANS-•look up
what is depression? - ANS-look down
what is dextrodepression?
- which muscles maximally used in this position? - ANS-•Dextrodepression = down + to
the right
- R inferior rectus + L superior oblique
what is dextroelevation?
- which muscles maximally used in this position? - ANS-•look up + right
- R superior rectus + L inferior oblique
what is laevoelevation?
- what muscles maximally used in this position? - ANS-•up + left
- R inferior oblique + L superior rectus
what is laevodepression?
- what muscles maximally used in this position? - ANS-down + left
- R superior oblique + L inferior rectus
what muscles are working in primary position? - ANS-All muscles equally innervated by
a small amount
, which positions have 2 muscles being maximally used?
- why is this not a good position for detecting muscle weakness? - ANS-- elevation =
inferior obliques + superior rectus
- depression = superior oblique + inferior rectus
- we dont know which of the 2 muscles are weak
which positions are good for determining if an EOM is weak?
- what are these positions known as? - ANS-- dextroversion = R lateral rectus + L
medial rectus
- laevoversion = L lateral rectus + R medial rectus
- only 1 muscle in each eye is maximally used
- these are secondary positons
what would happen to the eye if you ask a px to look into dextroversion but their R
lateral rectus was weak? - ANS-px fails to aBduct the eye
•So the eye will be displaced inwards - the eye is esotropic compared to left one
what would happen to the eye if you ask a px to look into laevoversion but their R
medial rectus was weak? - ANS-•it fails to aDduct the eye
•So the RE would be exotropic in comparison to LE (would be more pulled out)
what are tertiary positions? - ANS-- dextroelevation + dextrodepression
- laevoelevation + laevodepression
where would we ask px to look if we wanted to investigate R inferior rectus weakness? -
ANS-dextrodepression - down + right
RADSIN
- recti ADDuct = look away from nose = to the right in RE
where would we ask px to look if we wanted to investigate a R superior oblique
weakness? - ANS-RADSIN
- recti ADDuct - so obliques - ABduct = towards nose = towards left
- superior obliques = depress eyes
- so we would ask px to look to laevodepression
