Block 11 Flashcards
(166 cards)
1
Q
A vision condition in which a person cannot align both eyes simultaneously
A
Strabismus
2
Q
4 types of neurological strabismus
A
Cranial Nerve Palsies
Neurological Diseases
Posterior Fossa Tumors or Malformations
Raised Intracranial Pressure
3
Q
Symptoms of strabismum
A
Double vision Blurry vision Reduced peripheral vision HA Dizziness
4
Q
All 3 of the CN palsies can be caused by
A
Vasculopathic
Tumor
5
Q
Aneurysms can cause which type of strab
A
3rd nerve palsy
6
Q
Which type of strab is usually caused by trauma or congenital
A
4th nerve palsy
7
Q
Which type of strab is caused by cranial pressure
A
6th nerve palsy
8
Q
What muscles are affected in CN 3 palsy
A
SR MR IR IO Sup palpebral levator muscle
9
Q
Which way will the eye be in a CN 3 palsy
A
Down and out
Ptosis
Dilated pupil
No accommodative response
10
Q
What nucleus can be affected in a 3rd nerve palsy
A
Edinger-Westphal nucleus
11
Q
Which etiology of CN 3 palsy is pupil sparing
A
Ischemic/vascular
12
Q
Most common arteries involved in CN3 palsy with an aneurysm cause
A
Posterior communicating a.
Also internal carotid a. Or basilar a.
13
Q
Muscle affected in CN4 palsy
A
SO
14
Q
Which way will the eye move in a CN4 palsy
A
Up and in
Usually with a head tilt
15
Q
Which way will the head tilt in CN4 palsy
A
To opposite side of palsy
Rt tilt –> LSO palsy
16
Q
Longest intracranial pathway is with which nerve
A
CN 4
17
Q
CN4 palsy is often associated with what type of syndrome
A
Horner’s
18
Q
Most common causes of acquired isolated CN4 palsy
A
1- idiopathic
2- head trauma
3- microvasculopathy (diabetes, HTN, atherosclerosis)
19
Q
Which muscle is affected in CN6 palsy
A
LR
20
Q
Which way does the eye turn in LR palsy
A
Turns in
Compensatory head turn
21
Q
Which way does the head turn in LR palsy
A
Towards affected eye
OD in –> turn to right
22
Q
CN6 has a long external course through the cranium, making it susceptible to
A
Injury Inc ICP Mastoid infection Skull fracture Tumors
23
Q
Most commonly affected oculomotor nerve in adults
A
CN 6
24
Q
Most commonly affected oculomotor nerve in kids
A
CN 4
25
Second most commonly affected oculomotor nerve in children
CN 6
26
Which muscle is more affected by ischemia than other EOMS and why
LR bc it only has 1 ant ciliary a., the rest have 2
27
If the cavernous sinus is affected, what nerves are affected
3, 4, 5-1, 5-2, 6
28
Main cause of a cavernous sinus palsy
Neoplasm
29
Orbital apex syndrome involves which nerves
3, 4, 5-1, 6
30
Which multiple nerve palsy is horners syndrome seen in
Cavernous sinus
| Orbital apex syndrome
31
Main cause of orbital axis syndrome
Neoplasms
32
Exo greater at near
Medial rectus palsy
33
Hyper and exo
Inferior rectus palsy
34
Bilateral
| V exo pattern
Superior rectus palsy
35
An A eso
Inferior oblique palsy
36
SR and IO of the same eye are affected
Double elevator palsy
37
In double elevator palsy, is there elevation in abduction and adduction
No
38
What is usually present in double elevator palsy
Bell's phenomenon
39
2 etiologys of double elevator palsy
Congenital
| Supra/nuclear defect
40
Possible differential diagnosis of double elevator palsy
```
Blowout fracture
Thyroid eye disease
Brown's syndrome
Congenital fibrosis of IR
General fibrosis syndrome
```
41
IR and SO of same eye are affected
Double depressor palsy
42
What does the head do in double depressor palsy
Chin down to compensate for hypertrophic eye
43
Lesion above the level of ocular motor nerve nuclei
Supranuclear neurogenic palsy
44
Where would a lesion be that causes an internuclear neurogenic palsy
Lesion of medial longitudinal fasiculus
45
In younger patients, what is often a cause of internuclear neurogenic palsy
MS
46
In elderly patients, what is often a cause of internuclear neurogenic palsy
Vascular origin
47
Presentations of nuclear neurogenic palsy
```
Unilateral CN 3 with bilateral ptosis
Unilateral CN3 with contralateral SR underaction
Isolated EOM palsy of IR, IO or MR
Brown's syndrome
Bilateral CN 3 with spared levator
```
48
Infranuclear neurogenic palsies can affect which CNs
3, 4, and 6
49
Cause of CN3 palsy: central sparing the pupil
Vascular
| -infranuclear neurogenic palsy
50
Cause of CN3 palsy: peripheral with pupil involvement
Aneurysm
| - infranuclear neurogenic palsy
51
If you suspect Na aneurysm, what test should immediately be ordered
Angiography or MRA
52
If suspect an neoplasm, what test should you immediately order
MRI or CT
53
First step in managing strabsimic symptoms is
Prescribing glasses
54
Short term treatment of diplopia with glasses is
Fresnel press-on prisms
55
Which eye do you put the fresnel prisms over
Nondominant eye
56
A short term treatment for diplopia that is often uncomfortable for patients
Occlusion
57
Common treatment for acute paralytic strabismus due to unilateral 6 nerve palsy
Botox
58
What does Botox do
Prevents ACh release, resulting in paralysis
59
What treatment often has temporary side effects that are uncomfortable to patients
Botox
60
What are possible Botox side effects
Soreness at side of injection, weakness in the injected muscle, muscle soreness in whole body, difficulty swallowing, red rash
61
Long term treatment for strab
Surgery
62
What are the possible risks with surgery correction
Mild discomfort after Sx, continued strab, endophthalmitis, ocular ischemia
63
What is a mechanically restricted muscle
EOM is tethered or a systemic disease reduces the elasticity
64
Are mechanically restrictive deviations congenital or acquired
Both
65
3 examples of a congenital mechanically restrictive deviation
Duane Syn, Brown’s Syn, Fibrosis Syn
66
2 examples of acquired mechanically restrictive deviations
Thyroid myopathy and trauma causing deviations
67
Forced duction test results in mechanically restricted muscle
Positive
68
Will you see a deviation in primary gaze in a mechanically restricted muscle
Will either be very small or ortho
69
Will alternate CT and prisms give accurate results when measuring the magnitude of a mechanically restricted muscle
No
70
What addition tests should you do to determine the magnitude of a mechanical deviation of 1 eye
Maddox rod/prism bar
71
If both eyes are restricted, which tests may be best for determining the amount of deviation in mechanically restricted muscles
Hirschberg or krimsky
72
Charazcterized by limitations in abduction, adduction, or both
Duane Syn
73
Type 1 Duane syn
Limited ABDuction
74
Type 2 Duane syn
Limited ADDuction
75
Type 3 Duane syn
Limited ABDuction and ADDuction
76
Most common type of Duane syn
Type 1
77
Least common type of Duane syn
Type 2
78
Is Duane syn usually unilateral or bilateral
Unilateral
79
What does the globe do in Duane syn
Enophthalmos (globe retracts)
80
What type of patterns may be seen when looking up and down in Duane syn
A/V patterns
81
Is Duane syn usually hereditary or sporadic
Sporadic
82
Is amblyopia usually seen in Duane syn
No
83
Head turns toward affected side in which type of Duane syn
Type 1
84
How is Duane syn different from LR palsy
Palsy: no retraction of globe, eso angle is larger, (-) forced duction, few vertical anomalous movements
85
Clinical pearl with Duane Syn
If a pt has limited abduction isn’t he absence of a significant strab in primary position, consider it Duane syn until proven otherwise
86
2 ways to treat Duane syn
Surgery - rarely improved abd/adduction, but improved field of bino vision, head turn is improved
Prisms - alleviate head postures
87
Superior oblique tendon sheath syn
Brown’s syn
88
Brown’s syn: usually unilateral or bilateral
Unilateral
89
Brown’s syn: more in OD or OS
OD
90
Brown’s syn: more in females or males
Females
91
What is Brown’s syn commonly due to
Thickening of the SO tendon
92
When the eye cannot elevate and adduct
Brown’s syn
93
Is Brown’s syn congenital or acquired
Usually congenital, but can be aquired due to injury or inflammation at the region of the trochlea
94
May have a V pattern in up gaze, but no A pattern in down gaze
Brown’s syn
95
May hear audible click when the eye elevates
Brown’s syn
96
Head posture with Brown’s syn
Chin elevation and pointing toward OPPOSITE shoulder
97
How is the palpebral fissure affected when trying to adduct with Brown’s syn
Widens
98
Is amblyopia common in Brown’s syn
No
99
How to tell the difference between Brown’s syn and IO paresis
IO paresis: hypotropia in primary, head tilt to affected side, A-pattern, can fulfill Parks3
100
Does Brown’s syn usually required treatment
No
101
When treating Brown’s syn, what is the primary treatment
Surgery
102
When treating Brown’s syn, what is the secondary treatment
Prism (yoked or BU)
103
Etiology of Duanes syn
Mechanical, anatomy (muscle insertions), or innervation
104
Head turns away from affected side in which type of Duane’s syn
Type 2
105
Lid changes in Duane’s syn
Narrowing
106
Lid changes in browns syn
Widening
107
Autoimmune, neuromuscular disorder characterized by the fatigability of voluntary striated muscles
Myasthenia gravis
108
Myasthenia gravis: more common in which gender
Females
109
Is MG congenital or acquired
Neonatal or congenital
110
Many experience initial symptoms during what in MG
Emotional upset
111
Etiology of MG
Abs block and destroy ACh receptors —> less nerve signals —> weakness
112
Which gland may trigger Ab production and be larger in MG patients
Thymus
113
2 forms of MG
Generalized and ocular
114
Hallmark of MG
Muscle weakness that worsens after activity and improves after rest
115
Which muscles are usually seen first with weakness in MG
Lid and EOM abnormalities
116
Generalized MG signs and symptoms
Weakness of arm and leg muscles
| Difficulties with speech, chewing, swallowing and breathing
117
Ocular signs and symptoms of MG
Ptosis
Diplopia
Nystagmus
118
Is ptosis usually unilateral or bilateral in MG
Unilateral
119
Difficulty with what muscles are common in MG
```
Orbicularis oculi
Masseter muscle
Sternocleidomastoid
Tongue
Diaphragm
```
120
When does myasthenia crisis occur
Muscles are too weak to control breathing
121
Are most thymomas in MG benign or malignant
Benign
122
Is thymus hyperplasia common in MG
Very common
123
3 things to look for when diagnosing MG
```
Ptosis with prolonged up gaze
Cogan’s twitch (when looking down, twitch when look up)
Ice test (2mm elevation after 2 minutes)
```
124
Presence of an inconsistent deviation along with ptosis and restricted ocular motility
Suspect myasthenia gravis
125
Ocular treatment for MG
Occlusion
126
Are prisms useful in ocular treatment of MG
No
127
An autoimmune disorder that results in overproduction of thyroid hormone
Graves’ disease
128
Common signs and symptoms of GD
```
Goiter
Weight loss
Heat sensitivity
Bulging eyes
Rapid, irregular heartbeat
Thick, red skin
```
129
Most common cause of spontaneous diplopia in middle age
GD
130
Will EOMs be larger or smaller in GD
Larger (reduced elasticity and motility)
131
Is GD usually unilateral or bilateral
Bilateral
132
Big risk factor for GD
Smoking
133
Common ocular signs of GD
```
Periorbital congestion
Proptosis (lid retraction)
Lid lag
Exophthalmos
Optic neuropathy
Impaired ocular motility
```
134
Patient symptoms with GD
Dry sensation, photophobia, excessive tearing, double vision, pressure behind eye, vision loss
135
GD: forced duction test results
Positive
136
Muscle most involved in GD (most to least)
IR MR SR LR
137
GD may be mistaken as paresis of which muscle
SR
138
Affected eye in GD often demonstrates
Restriction of elevation and abd
| HypoT in primary position
139
Other tests to help diagnose GD
```
Tonometry
Hertel exophthalmometer
Slit lamp
ON eval
CT
thyroid function tests
```
140
Ocular treatment of GD
```
Fresnel prisms
Surgery if stable for 6 months
Artificial tears
Cold compress for edema
Stop smoking
```
141
How to record limitations in ductions (2 ways)
- As a percentage of normal
- on a scale of -4 to +4
—minus is underaction, plus is overaction, 0 is normal
142
Different management options for fibrosis syndrom
Amblyopia Tx
Sx (for cosmetics and comfort)
Ptosis (dry eye)
Abnormal head posture
143
How to manage fibrosis syndrome if caught early
Amblyopia Tx
144
Is amblyopia seen in fibrosis syn
Yes
| - strab in primary gaze
145
Forced duction results with fibrosis syn
Positive
146
Do pts with fibrosis syn have bino vision
No
147
Genetics of fibrosis syn
Autosomal dominant
148
Is fibrosis syn usually congenital or aquired
Congenital but can be both
149
Which muscle is most likely to be fibrotic
IR
| - cause hypo deviation
150
Lids and head posture in fibrosis syn
Ptosis with chin elevation
151
Is fibrosis syn usually uni or bilateral
Bilateral
152
Severely restricted eye movement is seen what what syn
Fibrosis syn
153
Tissue of the EOMs are abnormal and replaced with fibrotic tissue
Fibrosis syn (CFEOM)
154
Maddox Rod: above the light
Left hyper
155
Maddox Rod: below the light
Right hyper
156
Maddox Rod: to the left of the light
Crossed
157
Maddox Rod: to the right of the light
Uncrossed
158
Worth 4 dot: only see 3 green
OD suppression
159
Worth 4 dot: only see 2 red
OS suppression
160
Worth 4 dot: 5 dots with red below green
Right hyper
161
Worth 4 dot: 5 dots with red to the left
Crossed
162
Worth 4 dot: 5 dots with red to the right
Uncrossed
163
How to treat uncrossed diplopia
BO
164
How to treat crossed diplopia
BI
165
Crossed
Exo
| - image hits temporal retina
166
Uncrossed
Eso
| - image hits nasal retina
