Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Binocular vision 2 > Heterophoria mangement > Flashcards

Heterophoria mangement Flashcards

1
Q

which 2 types of patients with heterophoria are appropriate to treat

A
  • Symptomatic patients

- Asymptomatic and decompensating (under 8 yrs old)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

why must you immediately treat an asymptomatic and descompensating heterophoria patient under the age of 8

A

they can end up with a constant tropia and can develop amblyopia and suppression
if they develop suppression, they won’t have any stereo vision and will struggle with driving, writing etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what 4 things does a complete full investigation consist of prior to deciding to treat a patient with symptomatic heterophoria

A
  • Diagnosis understood
  • Full BV work up
  • Fundus exam
  • Post refraction (cyclo for children)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

why must a full BV work up be investigated before treating someone with a heterophoria

A

if your going to manage with prisms, then you must be sure of the diagnosis and that your not making something worse underneath

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

which 3 things can help determine if someones symptoms are truly related to a phoria

A
  • From the history
    Convergence weakness XOP symptoms >near
  • Diagnostic occlusion
    Do symptoms stop after monocular occlusion?
    suggests heterophoria is decompensating
  • Diagnostic prisms
    Do symptoms stop after corrected
    suggests heterophoria is decompensating
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

list 6 clinical signs and symptoms that can indicate decompensation

A
  • Increase in symptoms
  • Increase in size of phoria
    speed of recovery reducing
  • Reduced fusional reserves
  • Reduced binocular controlled acuity
  • Reduced convergence
  • Reduced stereo-acuity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the 2 types of conservative treatment methods of a decompensating heterophoria

A
  • optical

- orthoptic exercises

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are the 2 types of optical treatment methods to treat a decompensating heterophoria

A
  • Manipulation of Rx
  • Prisms
    Fresnel
    incorporated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how will you manipulate an Rx for someone in order to reduce an esophoria and an exophoria and what does this Rx actually manipulate

A

Esophoria = +ve/convex lenses

Exophoria = -ve/concave lenses

manipulates accommodative convergence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the advantage of a fresnel prism

A

it is cheaper than having prisms incorporated and you can use them if you know the problem will get better before buying expensive incorporated lenses
so is good as a temporary measure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the non conservative treatment method of a decompensating heterophoria

A

surgery

done as a last resort

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

name 3 reasons that prisms are used for

A
  • For diplopia
    Give minimum horizontal correction
    Often need full vertical correction
  • To alleviate symptoms
  • Prevent decompensation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

how much prism should you give for horizontal diplopia

A

the minimal horizontal correction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how much prism should you give for vertical diplopia

A

often full vertical correction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what should you try first before prescribing prisms

A

try exercises if possible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are prisms only good for

A

they are a crutch

so just stops the symptoms but does not resolve the problem of a decompensating phoria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

which type of prisms can be used for a critical period/recent onset nerve palsy

A

fresnel temporary prisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what can prisms be used with if the deviation is too large

A

with the exercises

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

how should the prism be used if correcting the symptoms of a heterophoria

A

prism base always OPPOSITE TO DEVIATION.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

why must you give minimal possible prism for horizontal phorias

A

due to prism adaptation
as you get older, the teamwork of both eyes gets worse and if prisms are given at a young age, then you need to keep giving stronger prism powers as the patient gets older

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what are the 2 risks of prism usage

A
  • prism adaptation

- aetiology unknown could mask ocular or systemic pathology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

list 4 reasons when you will decide to give long term use of prisms

A
  • Elderly or poor general health
  • Small symptom producing vertical deviation (as we have a tiny amount of fusional reserves)
  • Refusal or unfit for surgery and exercises don’t work
  • Failed to respond to other forms of treatment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

list 6 types of patients who will make a good selection for orthophoric exercises

A
  • Good potential for BSV
  • V-A quite good in either eye
  • Motivated
  • Understands exercises i.e. can’t give to a 3/5 yr old child
  • Sufficient time
  • Good GH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

list the steps of how you will use a prim bar as an exercise to control a deviation e.g. RSOT to a phoria

A
  • Fuse images with prism (lend prism bar or Fresnel’s)
  • example RSOT
  • first correct with base out prism
  • Once corrected reduce prism strength while patient maintains BSV (nil diplopia), ask if they can still hold the image as one
  • Now use exercising prism base in (for ESOT) = same direction as deviation

and if the RSOT is due to convergence excess (i.e. at near the ESOT is getting worse)

  • Find the point of intersection (where they hold eyes straight) of visual axes by changing distance you hold fixation object
  • Now increase or decrease distance your holding the target at while asking them to maintain BSV (nil diplopia)

i.e. to make the eyes straight, pull the target back until the eyes are straight and then bring the target closer and see if the px can hold their eyes straight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

how can exercises to control a deviation to a phoria be used by manipulating accommodation

A

by:

  • Stimulating exophorias (Then reducing)
  • Relaxing it in esophorias (Then reducing)

in order to relax accommodation, ask the patient to make the target more blurry and therefore relax the eyes = eyes should start to turn out and if they can do that, then ask them to make the target clearer again

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what will an improvement of relative convergence/change in accommodation result in

A

a pre-determined change in accommodative convergence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

if accommodation is constant, what will happen to relative convergence as a result

A

relative convergence can be exerted or relaxed whilst maintaining static accommodation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

for every dioptre of accommodation how many dioptres of accommodative convergence will occur

A

5 dioptres of accommodative convergence occurs

AC/A = 5:1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what occurs in +ve relative convergence

A

Convergence is exerted in excess of accommodation

i.e. going to converge more than what we can accommodate

Relative convergence controls deviation whilst static accommodation keeps vision clear

you look infront of the target in order to see it clearly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

which type of heterophoria does +ve relative convergence exercises improve

A

exophorias

as we want them to converge more

31
Q

what occurs in -ve relative convergence

A

Convergence is relaxed relative to accommodation

Sufficient accommodation for clear vision without the associated convergence

you look behind the target in order to see it clearly

32
Q

which type of heterophoria does -ve relative convergence exercises improve

A

esophorias

as we want them to converge less

33
Q

where is the plane of vergence in relation to the plane of accommodation in +ve relative convergence exercises

A

plane of vergence is infront of the plane of accommodation

34
Q

where is the plane of vergence in relation to the plane of accommodation in -ve relative convergence exercises

A

plane of vergence is behind the plane of accommodation

35
Q

with relative convergence excerices, what do you want to keep constant and what do you want to change

A
  • Keep plane of accommodation constant

- Change stimulus to converge

36
Q

what 3 things can be used for relative convergence exercises

A
  • prism bar
  • prism flippers
  • stereograms
37
Q

which prisms are used for +ve relative convergence exercises

A

base OUT

which causes px to converge

38
Q

which prisms are used for -ve relative convergence exercises

A

base IN

which reduces convergence

39
Q

explain how the stereogram method is used

A
  • Each cat is incomplete in some way
  • Card held at approx. 33cms
  • Patient either fixates on:
    A pencil in front of the card (positive relative convergence)
    A distance object behind/through the card (negative relative convergence)
  • Position of the pencil changed until 3 figures are seen
  • Patient asked to maintain fusion while exerting accommodation for the appropriate distance to see clearly
40
Q

how frequently are patients advised to carry out exercises

A

Exercise for short periods frequently
Repeat each exercise once or twice 5 to 7 times daily
warn may have worsening of symptoms initially

41
Q

how often should you review a patient who is carrying out exercises

A

every 6 weeks

42
Q

what must you monitor a patient for who is carrying out exercises and when must you stop exercises

A

Monitor for spasm

if after exercises the px experiences constant diplopia that will not resolve then STOP

43
Q

what are the 2 risks of orthophoric exercises

A
  • intractable diplopia

- accommodative spasm (ask px to relax eyes after exercises)

44
Q

which 3 reasons will you decide to refer a px for surgery

A
  • Large angled heterophorias
  • Prevention of decompensation in children
  • If patient does not respond to conservative means

surgery is the last resort

45
Q

which muscle mainly works at near

A

medial rectus

46
Q

which muscle mainly works at distance

A

lateral rectus

47
Q

what procedure weakens muscles

A

recession

snip muscle off from insertion and then stitch on further back

48
Q

what procedure strengthens muscles

A

resection

snip muscle off from insertion, take a piece of it off and reattach it back to where it was originally inserted

49
Q

what is the optical management for someone with a convergence excess esophoria

A
  • Full correction hyperopia
  • Minimal correction myopia
  • If high AC/A ratio consider extra convex lenses

people will accept +ve at near

50
Q

what is the orthoptic exercise management for someone with a convergence excess esophoria

A
  • Increase negative base in (BI) fusional reserves (exercising divergent prisms) particularly at NEAR (where problem mainly is)
  • Negative relative convergence (stereograms), as want them to converge less
51
Q

which prisms will be used to manage someone with a convergence excess esophoria

A

Base out (BO) to relieving prism

52
Q

what surgery will be done for someone with a convergence excess esophoria

A

Bimedial rectus recessions

53
Q

what is the optical management for someone with a divergence weakness esophoria

A

Not suitable as:
Correction of refractive error has little effect
Extra plus will blur vision in distance

54
Q

what is the orthoptic exercise management for someone with a divergence weakness esophoria

A
  • Increase negative (BI) fusional reserves (exercising prism) particularly in the DISTANCE
  • Negative relative convergence (stereograms), as want them to converge less
55
Q

which prisms will be used to manage someone with a divergence weakness esophoria

A

Base out (BO) to relieving prism

56
Q

what surgery will be done for someone with a divergence weakness esophoria

A

Bilateral lateral rectus resections

57
Q

what is the orthophoric exercise management for someone with non-specific esophoria

A
  • Similar management to SOP convergence excess.

- Except negative (BI) fusional amplitudes are exercised at both near and distance

58
Q

what surgery will be done for someone with non-specific esophoria

A

medial rectus recession and lateral rectus resection

59
Q

what is the optical management for someone with a divergence excess exophoria

A
  • Full correction of any myopic error

- Consider extra minus

60
Q

what is the orthophoric exercise management for someone with a divergence excess exophoria

A
  • Increase positive (BO) fusional reserves (exercising prism) particularly in the distance
  • Positive relative convergence (stereograms), to pull eyes in
61
Q

which prisms will be used to manage someone with a divergence excess exophoria

A

Base in (BI) relieving prism

62
Q

what surgery will be done for someone with divergence excess exophoria

A

Bilateral lateral rectus recessions

63
Q

what is the optical management for someone with a convergence weakness exophoria

A
  • Full correction of any myopic error

- Consider extra minus

64
Q

what is the orthophoric exercise management for someone with a convergence weakness exophoria

A
  • Pen convergence, dot card, jump convergence
  • Increase positive (BO) fusional reserves (exercising prism) particularly at near
  • Positive relative convergence (stereograms)

all respond well to convergence exercises

65
Q

which prisms will be used to manage someone with a convergence weakness exophoria

A

Base in (BI) relieving prism

66
Q

what surgery will be done for someone with convergence weakness exophoria

A
  • Usually not required as responds well to exercises

- Bimedial medial rectus resections

67
Q

what is the orthophoric exercise management for someone with non-specific exophoria

A
  • Similar management to XOP convergence weakness.

- Except positive (BO) fusional amplitudes exercised at both near and distance

68
Q

what surgery will be done for someone with non-specific exophoria

A

medial rectus resection and lateral rectus recession

69
Q

what must you ensure with a patient who has a hyperphoria and a cyclophoria

A

Ensure no incomitancy

70
Q

when will you treat someone with a hyperphoria

A

only where they are symptomatic

71
Q

how will you treat someone who has a phoria with both a horizontal and vertical element

A

they dont respond well to exercises so instead:
1. correct vertical element only with prisms
or
2. correct vertical element with prisms and horizontal element with spheres

you try to do option 1 and treat the vertical element first as once you treat the vertical element first, they can use their horizontal fusional reserves to pull the horizontal deviation

72
Q

when will you refer someone with a hyperphoria

A

if recent onset or longstanding & symptoms persist

73
Q

how will you treat a cyclophoria

A
  • Repeat near subjective to check cyl axis or focimeter their glasses to make sure its correct
  • Difficult to treat (prisms of no value)
74
Q

list the 7 circumstances that you will refer

A
  • Any incomitancy: Urgent referral if recent onset
  • Significant increase in deviation: Urgent referral
  • Large angle heterophoria or failing to respond to treatment: Refer for possible surgery
  • Children under 7 years old: Hospital will watch them every few weeks to make sure they don’t decompensate and end up with amblyopia and lose their binocular functions
  • Unknown aetiology
  • Unexplained reduced visual acuity: Urgent referral if suspicious reduction
  • Anything you are unable to cope with

Binocular vision 2 (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions