management of concomitant esotropia Flashcards
1
Q
how will you correctly diagnose someone with the correct type of esotropia with refraction
A
Refraction with cycloplegia
- 0.5% cyclo under 6/12 of age
- 1% cyclo over 6/12 of age
2
Q
as well as cyclopegic refraction and glasses with correction, what else must you do in order to correctly diagnose someone with a concomitant esotropia
A
by reviewing the px after the cyclo refraction and carrying out a fundus check to rule out any pathology
3
Q
how is vision taken in order to manage a patient with a concomitant esotropia
A
- Best possible visual acuity in either eye
- Full hyperopic correction with glasses
- Treat amblyopia with patching if need be or glasses - aim is equal VA ( but may not always be possible if had poor vision to begin with, treatment can be difficult)
4
Q
why must you improve the alignment of the visual axes when managing a concomitant esotropia
A
To:
- Restore Binocular Single Vision (BSV) - if they have late onset esotropia
- Enhance Abnormal Retinal Correspondence (ARC)
OR
- Achieve an acceptable cosmetic outcome (if no potential for BSV or ARC, can use botox or do surgery etc)
5
Q
list the 3 things needed to be taken into consideration for the management of esotropia
A
- Cycloplegic refraction
- best possible VA’s in either eye
- improve the alignment of the visual axes
6
Q
list the 5 possible management options for treating a concomitant esotropia
A
- Optical - Full hyperopic correction too all px with esot/prisms
- Orthoptic Exercises
- Surgery
- Botulinum Toxin Type A injections
- Combination of the above
7
Q
when is orthoptic exercises a good management option for a concomitant esotropia and why
A
- it is good especially if the patient has a decompensating deviation
- because they have more potential to correct the angle of deviation
- especially in those with a near or distance esot
8
Q
for which type of concomitant esotropia is surgery a good option for and for which is it not a good option for
A
- good for all esotropias except for accommodative esotropia
- it is good for large angle esotropia and convergence excess esotropia
9
Q
on which type of patients will you carry out botox on more and under which procedure conditions
A
- carried out on children more than adults
- patient has to be on general anaesthetic if they’re below the age of 12
10
Q
why is a full hyperopic correction given to patients with an esot and which group of patients is it given to more
A
- Relax accommodation and thus reduce convergence
- Most common in children
11
Q
which 3 possible effects will a full hyperopic correction/glasses have on a squint when worn
A
- 1/3rd children fully correct squint
- 1/3rd partially correct squint
- 1/3rd have no effect on angle of squint
12
Q
on which type of squint will a hyperopic correction fully correct
A
- a child with a fully accommodating esot
- this type of child will have BSV/ESOP with the spectacle correction on
- no exercises or surgery is needed
13
Q
on which type of squint will a full hyperopic correction only partially correct the squint
A
- a child with a partially accommodating esot
- this type of child will still be manifest
- however the squint will be reduced and hence not as noticeable with glasses
14
Q
on which type of squint will a full hyperopic correction have no effect on the angle of the squint
A
- a child with a non-accommodating esot
- this type of child will be manifest with the same amount of angle with or without the correction
15
Q
which type of prism will you give to a patient with a concomitant esotropia
A
- base out prism
- either as Fresnels prisms or incorporated into glasses
16
Q
which type of patients will you give a prism to for correcting their esot
A
- patients with a late onset esot, where they will have diplopia
17
Q
which type of patients is prisms rarely used on
A
- in paediatric patients
- as we don’t want them to get used/dependent on them
18
Q
other than to permanently correct someone with an esot with prisms, which 2 other occasions will you use prisms on a patient with an esot
A
- Investigate binocular function before proceeding with surgery i.e. on a patient with a late onset esotropia: done using fresnel prisms, if when angle of deviation is corrected by surgery, are they still going to get double vision?
- Assess risk of diplopia post-operatively: if they will get diplopia or are they suppressing with a prism bar
19
Q
what will orthoptic exercises be used to improve
A
- negative relative convergence
- due to patients with over accommodation, to help them diverge more
20
Q
which type of esot/squint will orthoptic exercises work on only
A
Only used in INTERMITTENT convergent squint
21
Q
name 2 appliances that can be used for orthoptic exercises to improve negative relative convergence
A
- stereo grams
- dot pad
22
Q
on which acting muscles will surgery for correcting an esot be performed on, and which type of surgery on which type of muscles
A
- Usually performed on horizontally acting muscles
Recession (weakening) of medial rectus
Resection (strengthening) of lateral rectus
23
Q
which type of surgery is conducted on someone with a esot greater at near
A
Both medial rectus recessions
24
Q
which type of surgery is conducted on someone with a esot greater at distance
A
Both lateral rectus resections
25
which type of surgery is conducted on someone with a esot where near angle = distance angle
MR recession and LR resection on one eye/each eye
26
what type of treatment is a Botulinum Toxin Type A injection (BTXA)
an outpatient treatment
27
what is Botulinum Toxin Type A
a neuro-toxin which paralyses muscle into which it is injected
28
how is Botulinum Toxin Type A used to treat a strabismus
- strabismus it is injected into one or more of the EOM to cause paralysis thus giving the antagonist an advantage
- injected into the medial rectus for esotropia
29
how will Botulinum Toxin Type A be used on a patient with a small esot and a moderate esot
- small esot: inject into one MR of the affected eye
| - moderate esot: inject into MR of both eyes
30
list 4 advantages of Botulinum Toxin Type A for use in esot
- Preferred by many patients with consecutive /residual or secondary deviations
- Useful in cases where previous surgery undertaken
- Very useful if diplopia is suspected (post-op diplopia test)
- Used when patient is unfit for GA
31
what is the post-operative management for an amblyopic esotropic child
Monitor amblyopia until the end of visual development (8 years)
- maintenance occlusion
i.e. we still want to continue with occlusion treatment if are undergoing already, so want to carry on to get the best outcome
32
what is the post operative management for Residual and Consecutive deviations
they may need treatment in the future
- Residual: their post-operative esotropia will be better than their pre operative deviation, however they can suddenly decompensate and get a large angle esotropia, therefore may need more treatment in the future
- Consecutive: they can become an executive exotropia post operatively, and if it's fairly small angled then you don't need to do anything about that
33
what is the two classifications of primary esotropia
- constant
or
- intermittent
34
what is the management of an intermittent accommodative esotropia, and name the 2 types of accommodative intermittent esotropia that this management falls into
Order full plus, allow only for working distance
- Fully accommodative esotropia: when they're straight and binocular with their specs, and esotropic without their specs
and
- Convergence excess esotropia: they're straight and binocular at distance with their full +ve rx, but esotropic at near when they're accommodating but could be straight at near when looking at a non-accommodative target (e.g. to a light)
35
what do children who have an intermittent accommodative esotropia usually do if they're 5 y/o
- if under 5 years old, the child will usually suppress when removing their glasses
- if over 5 years old, the child may complain of diplopia when removing their glasses
36
what are fully accommodative esotropias able to do without their glasses
able to relax accommodation (BSV but vision blurred)
37
what will happen if a fully accommodative esotropia exerts accommodation without their glasses
they will have an esotropia
38
which power of glasses will a child with fully accommodative esotropia need to wear their glasses forever
If >+3.00 DS and 1 DC
39
what can you teach a fully accommodative esotropic px that is wearing glasses less than +3.00DS and 1 DC to do to make their eyes look straight and what are the 3 ways of achieving this
can teach control without glasses i.e. straight eyes without glasses for photos etc
- Recognition of diplopia
- Relaxation of accommodation to give ONE blurred image “misty and clear” (makes the image blurry and hence the eyes straight)
- Improve BVA by exertion of negative relative convergence using exercises
40
what can you teach a fully accommodative esotropic px that is wearing glasses of more than +3.00DS to do to make their eyes look straight
the "misty and clear" method (taught to older children)
if the px takes their glasses off and makes the image clear, then this means their accommodating and hence will be squinting, however if they take their glasses off and keep the image blurry, their eyes will be straight
you can also get the patient to recognise the real image of their diplopia without their glasses, if they do appreciate the diplopia, then the eyes are over accommodating and hence will be turning in
41
what treatment is never indicated in children with fully accommodative esotropia and why
surgery is never indicated
| because the full hypermetropic rx is perfectly controlling their esotropia
42
which type of esotropia can be managed my optometrists and why
fully accommodative esotropia
| because the patient does not need any further treatment apart from their full hypermetropic correction
43
what should be treated with a convergence excess esotropia, even if theres any or even slight (due to it being intermittent esotropia)
any amblyopia
44
what is the reason for someone having a convergence excess esotropia
they have a high AC/A ratio
45
what is the aim of treatment for someone with a convergence excess esotropia
to give BSV at all distances with the glasses if hypermetropic i.e. turn into fully accommodative esotropia
46
why is amblyopia rare or slight in a convergence excess esotropia
because it is an intermittent esotropia
47
when does the esotropia occur in a convergence excess esotropia
on accommodation at near
48
when is no deviation seen with a convergence excess esotropia
- when fixating on a light at near, as the px is not accommodating
and
- on distance fixation with hyperopic correction
49
what does the high AC/A ratio present in someone with a convergence excess cause
esotropia at near on accommodation
50
which type of treatment is suitable for patients with convergence excess esotropia and how is this treated
- Executive Bifocals – give minimum extra +ve for reading to achieve a BVA of 6/6 with reduced Snellens
- The amount of add is slowly reduced e.g. by –0.50DS every 6 months (on average), this is done by putting up a -0.50D lens in front of reading rx and see if px is still orthophoric
51
what is the aim of bifocals which are reduced by -0.50D every 6 months to treat a convergence excess esotropia
to achieve BSV for near and distance with a single focus lens
52
what is the contra indication of using bifocals to treat a convergence excess esotropia
If there's a large deviation and very high level of the AC/A >10:1
you can't give the patient any bifocal add
53
as well as bifocals, what else is available as treatment for a convergence excess esotropia and what type
- surgery
| - both medial rectus recessed (weakened as larger angle for near than distance)
54
when may a patient need further surgical operation for a convergence excess esotropia
if the px still has a manifest deviation
55
what is considered to be a normal AC/A ratio
2-4:1
56
when may a convergence excess esotropia px still need to use bifocals post-operatively
if they're still becoming esotropic for near on accommodation
they will be straight at distance but will have a small esot at near
therefore treatment can be a combination of surgery and bifocals if surgery not 100% successful (in cases of very high AC/A ratios)
57
what is normal in a non-accommodative esotropia and what is the symptom/sign of a non-accommodative esotropia
Normal AC/A ratio
straight and binocular for distance but manifest and suppression at near
58
what is a non-accommodative esotropia for near not related to and what is it more commonly related to
- not related to accommodation
- convergence excess is much more common
if you shine a light into the px eye, they will still be esotropic, these patients have a normal AC/A ratio (which is the difference with non-accommodative and convergence excess esotropia)
59
what is the treatment option for someone with a non-accommodative esotropia and which type
Surgery
| Recess both medial recti
60
which group of patients is a non-accommodative distance esotropia usually found in
adults
61
what happens to someone with a non-accommodative distance esotropia over time
gradually increases
62
what must you ensure that a patient with a non-accommodate distance esotropia does not have and how is this seen
a LR/6th nerve palsy i.e. their abduction should be full
63
what 2 things is a non-accommodative distance esotropia associated with
- age
or
- myopia
64
what are the 2 treatment options for someone with a non-accommodative distance esotropia
Prisms - Base out
| Surgery - Resect both lateral recti
65
why will you use base out prisms to treat a patient with a non-accommodative distance esotropia and when will you use this over surgery
- because they're adults, base put prisms is needed to manage their diplopia
- prisms used over surgery especially if the esotropia is gradually increasing
66
when will surgery be suitable for a person with a non-accommodative distance esotropia
if its a large stable esotropia
67
what is non-specific non-accommodating esotropia
Esotropia intermittently occurs for near and distance
68
which group of patients is a non-specific non-accommodating esotropia more common in
adults
69
what can be used to treat a non-specific non-accommodating esotropia if the deviation isn't too large
If glasses are worn may be able to use base out prisms
70
other than base out prisms in glasses, what other treatment option is there for a non-specific non-accommodating esotropia
- BTXA but surgery more likely
| Surgery on one eye medial rectus recession and lateral rectus resection
71
what type of surgery is carried out on someone with a non-specific non-accommodating esotropia
on one eye medial rectus recession and lateral rectus resection
72
when will BTXA be used on a patient with a non-specific non-accommodating esotropia and which muscles will it be injected in
- if its a large angle and decompensating more readily compared to it being straight and binocular
- BTXA is injected into the medial rectus muscle to correct this
73
what is a cyclic esotropia
- a esotropia thats related to time
- The “cycle” is usually 24hrs initially
i. e. esotropia one day and straight with BSV/suppression the next day
- Pattern becomes disrupted over time and the deviation becomes constant
74
what can happen to a cyclic esotropia over time
the 24 hour pattern becomes disrupted and the deviation becomes disrupted
75
when will you manage a patient with cyclic esotropia and that will the management be
- when the patient's esotropia becomes constant esotropia from the cyclic esotropia
- Surgery is indicated on one eye
Medial rectus recession and lateral rectus resection
76
what type of surgery is indicated on someone with a constant esotropia from having a cyclo esotropia first
Medial rectus recession and lateral rectus resection on one eye only
77
at what age is the onset of a constant non-accommodative esotropia most commonly found
Esotropia onset >6 months of age – usually onset at approx 1 year
78
what is not found in a constant non-accommodative esotropia
no hypermetropic correction
79
what is the aim of surgery in a child who has a constant non-accommodative esotropia and why
Surgery in childhood aiming to leave slightly esotropic/under corrected to delay the risk of consecutive exotropia and encourage development of ARC
80
what is the treatment option for an older child and adult patient with a constant non-accommodative esotropia
BTXA
for younger children, can do under general anaesthetic
81
what is the aim of surgical treatment for a constant non-accommodative esotropia/infantile/early onset esotropia
to align the eyes surgically within the first 2 years of life as may develop some anomalous BV
so want to rectify the esotropia as quickly as possible
82
what are the 2 surgery options for someone with a constant non-accommodative esotropia/infantile/early onset esotropia
Either:
- bi-MR recessions
OR
- MR recession and LR resection (surgery preference)
83
when will a bi medal rectus recession be done on a child with a constant non-accommodative esotropia/infantile/early onset esotropia
if the esotropia is greater at near than at distance
84
when will a MR recession and LR resection be done on a child with a constant non-accommodative esotropia/infantile/early onset esotropia
if the esotropia is equal at distance and at near
85
why is it important to monitor a child who had a constant non-accommodative esotropia/infantile/early onset esotropia post operatively
as surgery often disrupts pattern of alternation – amblyopia develops and so need occlusion therapy
86
list 4 reasons why the follow up monitoring of a child who has undergone surgery for a constant non-accommodative esotropia/early onset/infantile is important
- Occlusion: to rectify any amblyopia they have post-operatively and regular refraction: annually under cycloplegic refraction
- Development of Inferior oblique overreaction
- Development of Dissociated Vertical Deviation (DVD) which may need surgery (where the eye elevates under the cover)
- Development of latent nystagmus: which is present with both eyes open
87
when does a constant non-accommodative late onset esotropia usually present
over the age of 4 years old
88
what is the 2 treatment options for a patient with a constant non-accommodative late onset esotropia and explain under what conditions each treatment is done
- In sudden onset esotropia without any pathology, BTXA is used with excellent results for restoring BSV, but px still needs a cycloplegic refraction and fundus examination
- Surgery if esotropia returns after toxin wears off
MR recession + LR resection
but if once the botox has worn off and the eyes are still straight and binocular, then nothing else needs to be done
89
what type of surgery is done on a px who has a constant non-accommodative late onset esotropia
MR recession + LR resection
90
what is a constant accommodative esotropia sign
Esotropia which reduces but is not fully corrected when wearing hypermetropic correction
91
what other esotropia is a constant accommodative esotropia more common than
than non-accommodative esotropia
92
what must be treated for a child with a constant accommodative esotropia
amblyopia - by patching
93
what 2 things does further treatment of a child with a constant accommodative esotropia depend on
- size of squint
| - retinal correspondence
94
when do you not need to do anything in terms of treatment with a patient who has a constant accommodative esotropia and why and what just needs to be done instead
- do not need to do anything regarding a small angle esotropia with ARC
- this is because they should have good cosmesis and some form of retinal correspondence
- just make sure the patient has up to date glasses and any amblyopia is corrected
95
what is there a risk of with surgery for someone who has a small angle less than 20 prism dioptres of constant accommodative esotropia if treating with surgery and what should be done instead to avoid this
theres a risk of consecutive divergence/exotropia with surgery so BTXA injection indicated to medial rectus
96
what are larger deviations of someone with a constant accommodative esotropia unlikely to have and therefore what treatment option is best for these patients
- ARC or NRC
- surgery is indicated to improve cosmesis
- MR recession and LR resection
97
what type of surgery is done on a patient with a constant accommodative esotropia
MR recession and LR resection
98
what 2 reasons may you use BTXA in older patients with a constant accommodative esotropia for
- BTXA diagnostically to assess risk of post-operative diplopia
and
- therapeutically as alternative to surgery
if they do have a high risk post operatively, you don't want to do anything regarding that initial angle of squint, all you need to do is to wait for the injection to wear off and once its worn off, the squint will go back to its original angle and the patient will be suppressing
99
what cases is BTXA useful in for patients with a constant accommodative esotropia
where the patient has had multiple surgical procedures and still remains significantly esotropic
100
what is a consecutive esotropia
Esotropia as a result of surgical overcorrection of an exotropia
101
what 2 types of consecutive esotropia are there, and which type is more common
- constant
or
- intermittent
more common/most likely to be constant
102
what does a patient with a consecutive esotropia have no form of and what is done to avoid this problem
- they have no binocular vision ARC or NRC when they have a consecutive esotropia
- Aim: Slight esotropia is the desired outcome of a surgery, so over correct the patient if the patient is exotropic, this is because exotropia tends to become more divergent over time
103
why should you watch carefully in a child who has had an intermittent exotropia that is now is a consecutive esotropia
as BV can be lost and amblyopia develop
104
what is 3 possible treatment/management options for if a large angle consecutive esotropia deviation persists and is cosmetically unacceptable
- Duction exercises if abduction limited
- Botulinum toxin injection (to correct it post operatively)
- Further surgery
105
what is a secondary esotropia
Esotropia secondary to loss or impairment of vision
106
what are the 2 treatment/management options for someone with a secondary esotropia and why
Surgery and/or BTXA
for cosmetic alignment
107
what type of procedure is surgery for a secondary esotropia
- a uniocular procedure
- MR recession and LR resection (in one eye) as near and distance angle is fairly similar in both eyes and in adults adjustable sutures are used
108
what is the aim of surgery on someone with a secondary esotropia and why
Eso deviations tend to reduce with the passage of time so aim to leave slightly eso to delay development of consecutive exotropia
109
overall, what 2 things is the various methods to manage esotropia dependent on
- potential binocular status
and
- cosmetic alignment
110
having previous surgery to treat an esotropia does not.....
prevent further surgery later in life, it is normal to have three or more procedures over a life time
111
BTXA can be used as an alternative to.....
surgery
