Block 12 Flashcards
(160 cards)
1
Q
Involuntary rhythmic oscillation of 1 or both eyes
A
Nystagmus
2
Q
Can be a sign of visual pathway lesion or an ocular control abnormality
A
Nystagmus
3
Q
Type of waveform of nystagmus: has both quick and slow components
A
Jerk
4
Q
Which way is the slow phase in a jerk nystagmus
A
Away from the target
5
Q
Which way is the fast fast in jerk nystagmus
A
Back to fixation
6
Q
How is jerk nystagmus characterized
A
Direction of fast phase
7
Q
Type of waveform of nystagmus: to and fro movements of equal velocity in each direction
A
Pendualr
8
Q
Type of waveform of nystagmus: doesn’t have a fast phase
A
Pendular
9
Q
Which phase of jerk nystagmus reflects the abnormality
A
Slow
10
Q
Slow movement to the right with a fast corrective jerk movement to the left
A
Left jerk nystagmus
11
Q
The size/extent of the movement during nystagmus is known as the
A
Amplitude
12
Q
From what 2 points in nystagmus is the amplitude measured
A
From the start of the drift away tot he start of the corrective movement
13
Q
Number of oscillations per unit time in nystagmus
A
Frequency
14
Q
Fast frequency nystagmus is how quick
A
> 2Hz
15
Q
1 Hz equals
A
1cyc/sec
- a full rotation in 1 second
16
Q
Frequency of a slow nystagmus is what time
A
<2Hz
- need a slit lamp to view
17
Q
Where the intensity of the nystagmus diminishes and the VA improves
- may be associated with head position
A
Null point
18
Q
With latent nystagmus seen with occlusion, the fast phase is towards
A
Uncovered eye
19
Q
What does latent nystagmus usually indicated
A
A congenital condition
20
Q
Anterior seg conditions with nystagmus (3)
A
Congenital cataract
Congenital glaucoma
Iridocorneal dysgenesis (didnt form properly)
21
Q
Foveal condition associated with nystagmus
A
Foveal hypoplasia in albinism (flattening)
22
Q
Optic nerve/retinal disorders associated with nystagmus
A
Coloboma of ON head (fissure doesn’t close)
ON hypoplasia
Toxoplasmosis
23
Q
Do children with congenital nystagmus usually complain about issues
A
No
24
Q
Nystagmus from motor coordination
A
Less VA loss (better VA)
25
Nystagmus from sensory issues
More VA loss (worse VA)
26
Do you allow patients to use their preferred head position when doing VAs?
Yes bc this will allow you to asses true functional vision
27
When doing monocular VAs, you may have to use a high plus lens to blur instead of occlude because
You need to allow fusion so that the jerk nystagmus intensity doesn’t increase
28
When refracting pts with nystagmus, do you use the phoropter
No, need to see the nystagmus
| - use trial lenses or a lens bar
29
CT may be difficult in patients with nystagmus. What can you use to determine if the reflexes appear symmetrical
Hirschberg/krimsky
| Bruckner
30
Do you use occluder in Pts with nystagmus during CT and VA
No, use a high plus lens (+2 - +5)
31
For IOP, what do you use in pts with nystagmus
NCT or tonopen
32
Slit lamp is important in detecting the presence of
Iris coloboma or transillumination
33
In recent/acquired nystagmus, what 2 tests should be done asap
CT/MRI for neuro eval
34
Sensationof the environment moving
Oscillopsia
35
Position of gaze where eyes are quiet
Null point
36
- small amp and variable freq
- intermittent conjugate jerk (fast in direction of gaze)
- seen in both eyes when extreme lateral gaze is held (>30 degrees)
- symmetrical in rt and lt gaze
End point nystagmus
37
Pts with which type of nystagmus may fail road side sobriety test
Endpoint nystagmus
38
- jerk nystagmus due to rotation
- related to endolymph in semicircular canals
- slow conjugate mvmt then fast phase OPP of rotation
Rotational nystagmus
39
Which way is the fast phase in rotational nystagmus
Opposite of the rotation
40
Nystagmus type seen when putting water in semicircular canals
Caloric nystagmus
41
Normal response in Caloric testing
Cold water: fast toward opposite ear
| Warm water: fast toward ipsilateral ear
42
Slow pursuit eye movement followed by fast corrective saccade bc VF moves over the retina
OKN (optokinetic nystagmus)
43
Is the head still or moving when testing OKN
Head is still
44
When is the OKN developed
3-5 months
45
What will a child’s OKN response be if they have congenital nystagmus
Reverse OKN response
46
Congenital nystagmus: which gender
Boys twice as often
47
Congenital nystagmus: is family hx likely
Yes
48
Congenital nystagmus: etiology mostly afferent or efferent
Efferent 60% (afferent 40%)
49
Pendular and/or jerk nystagmus
- horizontal
- no oscillopsia
- active fixation may increase nystagmus
Congenital nystagmus
50
Congenital nystagmus: is VA good
At null point it is good
51
Congenital nystagmus: when converging, what happens to nystagmus
Decreases
52
Which etiology of Congenital nystagmus will have better vision
Efferent etiology
53
Possible afferent etiological of Congenital nystagmus
Optic atrophy, ON hypoplasia, retinal dystrophy
54
Pt with Congenital nystagmus that later envelops esotropia bc of attempts to suppress nystagmus by converging
Nystagmus blockage syndrome
55
May look like 6 nerve palsy, but there is an ability to abduct the eye
Nystagmus blockage syndrome
56
Congenital, jerk nystagmus after occlusion of one eye
Latent nystagmus
57
Which way is the fast phase in latent nystagmus
Toward uncovered eye
58
Latent nystagmus may increase with the disruption of
Fusion
59
- Starts shortly after birth
- pendular nystagmus
- bilateral usually
- high-frequency
- head nodding
- torticollis
Spasms nutans
60
Eye movements like those in spasmus nutans are similar to those seen in
Chiasmal tumors, glioma and craniopharyngioma and retinal dystrophies
Send to neuro!!
61
- Pendular
| - 1 eye elevates and intorts while the other depresses and extorts
See-saw nystagmus
62
- Lesion in the suprasellar area may cause
- craniopharyngioma
- Joubert syndrome
See-saw nystagmus
63
- vertical jerk nystagmus (fast beats down)
Downbeat nystagmus
64
- vertical jerk nystagmus (fast beats up)
Upbeat nystagmus
65
Etiologies of downbeat nystagmus
- craniocervical junction
| - medications
66
Etiolgies of upbeat nystagmus
- brainstem abnormalities
| - drugs
67
Horizontal jerk with a rotary element
| - inner ear or vestibular abnormalities
Vestibular nystagmus
68
Hearing loss is common in which nystagmus type
Vestibular nystagmus
69
What 3 things are often seen in vestibular nystagmus because of the dysfunction of vestibular system
Oscillopsia, nausea, vertigo
70
Rhythmic convergence and retraction of eyes when attempting upgaze moment
Convergence-retraction syndrome
71
Often seen in parinaud syndrome
Convergence-retraction syndrome
72
Hallmark sign of periodic alternating nystagmus
Shifting null point
73
Possible etiologies of periodic alternating nystagmus
- degeneration of cerebellum
| - skew deviation
74
How often does direction change in periodic alternating nystagmus
Every 90 seconds with about 10 seconds of rest between
75
How may patient adapt to periodic alternating nystagmus
Alternating head turns
76
what kind of prisms do you use to move a patients null point
yoked prism
77
what should be considered first to help improve the clarity of the retinal image and lessen the nystagmus
refractive correction
78
type of add: used at near to improve VA and aid in accomodation
plus adds
79
type of add: induce convergence since nystagmus could decrease with convergence
minus adds
80
which direction of prism is used to induce convergence to dampen nystagmus
BO
81
what are yoked prisms
base is placed in the same direction over each eye
82
for anomalous head position, which way are the bases placed in yoked prisms
base in same direction as head turn
83
images are shifted toward which part of the prims
apex
84
which type of prism is used for large amounts of prisms but also degrades the vision
fresnel prisms
85
when using fresnel prism, the apex is placed toward what? base?
apex - the null point
| base - towards turn
86
if a pt has a left head turn, the pt has the null point in the right gaze, which direction will the bases go over each eye to shift the image and reduce the head turn?
bases to the left
87
when is occlusion treatment used
amblyopia (consider using a high plus lens instead of straight occlusion to not break fusion)
88
what is the purpose of vision therapy
for fusion vergences or to improve motor control
89
when can meds be used to help with nystagmsu
if it is due to a system problem (infection, metabolic or vascular issue)
90
what is a common medication that helps reduce the severity of nystagmus, but there are adverse effects to it
gabapentin
91
what is the kestenbaum technique in surgical nystagmus correction
shift the null point to closer to primary postion and eliminate the head turn
92
what is the minimum age cutoff for surgical nystagmus correction and why
older than 4 bc of the risk of overcorrection in younger
93
spontaneous upward movement of one or both eyes when tired, fusion is broken or inattentive
dissociated vertical deviation (DVD)
94
what is often found with infantile strabismus
DVD
95
is DVD usually treated
no
96
if the eye is elevated in adduction
IO overaction
97
this is mainly present in children with infantile strabismus
IO overaction
98
found in 2/3 of children with congenital strab
IO overaction
99
present when a horizontal deviation changes in magnitude between up and down gaze
pattern strab
100
horizontal deviation is more divergent in upgaze
V pattern
101
horizontal deviation is more divergent in downgaze
A pattern
102
when is the V pattern clinically significant
difference between up and down gaze is >/= 15pd
103
most common pattern deviation
V pattern
104
which pattern deviation is seen in infantile ET
V pattern
105
which pattern deviation is seen in SO palsies
V pattern
106
if pt has a V pattern deviation, what head position may they have
chin elevation
107
when is teh A pattern clinically significant
difference between up and downgaze in >/= 10pd
108
pattern deviation seen more frequenetly with XT
A pattern
109
head psition in pt with A patten
chin down
110
more common in pts with infantile strab associated with craniofacial malformations, down's
A pattern deviation
111
When it comes to management plan, what is it important that you do with your patient
Communicate about their condition and the plan
| - explain pros and cons
112
What kind of lenses will decrease ESO (dec accom)
Plus lenses
113
What kind of lenses with decrease EXO (inc accom)
Minus lenses
114
You put the fresnel prims over which eye
Nondominant
115
The eye will move toward which part of the prism
Base
116
Short term treatment for diplopia
Monocular occlusion
117
Treatment for acute paralytic strab due to unilateral 6th nerve palsy
Botox
118
What does Botox do
Stops release of ACh at NMJ resulting in paralysis
119
Which way will the eye turn in 3rd nerve palsy
Down and out with ptosis
120
Optical tx of 3rd nerve palsy
- Glasses
| - fresnel prism
121
Pharm Tx of 3rd nerve palsy
- tx underlying condition
| - immediate care if suspect aneurysm or tumor
122
Possible causes of CN3 palsy
- vascular
- tumor
- demylinating disease
123
Possiblecauses of CN 4 palsy
- idiopathic
- head trauma
- vascular
124
Optical tx of CN 4 palsy
BI, BD prims
125
What palsy’s do you consider surgery for if it doesn’t resolve
4 and 6
126
Possible cause of CN 6 palsy
- trauma
- vascular
- tumor
127
Optical tx of cn6 palsy
BO prism
128
Inability of one eye to attain bino vision bc of imbalance of muscles
Strabismus
129
Primary tx of strab
Refractive correction
130
ET due to uncorrected hyperopia
Refractive accommodative ET
131
ET due to high AC/A
| - greater at N
Non refractive accommodative ET
132
ET due to high hyperopia and high AC/A
Mixed accommodative ET
133
Which kind of accommodative ET may require refractive Sx
Refractive accommodative ET
134
Onset of infantile ET
Birth to 6mo
135
Onset of early onset non-accommodative ET
6mo to 2yr
136
Type of ET due to vision loss in one eye
Sensory ET
137
What should you do to a pt with divergence insufficiency ET
Neuro referral
138
ET after XT surgery
Consecutive ET
139
Deviation is latent at times, manifest during visual inattention, fatigue or stress
Intermittent XT
140
Exo greater at N, low AC/A, receded NPC
Convergence insufficiency XT
141
Optical Tx of convergence insufficiency XT
BI reading glasses
142
Spectacle correction for someone with sensory ET or XT
Glasses with polycarbonate lenses
143
Type 1 Duane’s
Can’t abduct
144
Type 2 Duane’s
Can’t adduct
145
Type 3 Duane’s
Can’t ab or adduct
146
Optical XT for duanes
Prism
147
Do you do Sx for duanes?
Yes if significant strab in primary, head posture, to improve field of bino vision
148
Restricted elevation in adduction
Browns
149
Optical Tx for brown’s syndrome
BU or yoked prism
150
What is the primary Tx for browns
Sx
151
Do most Brown’s pts require Tx
No
152
Autoimmune, NM disorder; fluctuating weakness of voluntary muscle groups
MG
153
Optical Tx for MG
Occlusion
154
Sx for MG?
Not usually (spontaneous remission in 30% of pts)
155
Autoimmune overprod of thyroid hormone, affecting orbital tissues an EOMs
Graves
156
Optical Tx of Graves
Prism (fresnel)
157
Sx for graves?
Yes, for significant deviations if stable for 6 mo
158
Other ways to Tx Graves
Tx of dry eye, cold compresses, smoking cessation
159
Tissue of EOMs replaced with fibrotic tissue; restricted eye movements, ptosis, chin elevation
Fibrosis syn
160
Do you do Sx for fibrosis syn
Yes, if have significant strap in primary
