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Neuro-ophthalmology Illustrated Chapter 13 Diplopia 11 – Vertical Eye Movements

February 5, 2020 By

Questions:

135. Where are the critical supranuclear structures mediating vertical gaze located?
136. What are the 4 most important pretectal areas related to vertical eye movement?
137. Where are the burst neurons responsible for vertical saccades located?
138. What serves as the neural integrator for vertical gaze and torsion?
139. For downgaze, where do the axons from the interstitial nucleus of Cajal (INC) project?
140. What are the 4 findings of the Dorsal Midbrain Syndrome?
141. What are 2 other names for the Dorsal Midbrain Syndrome?
142. What is a common cause of the Dorsal Midbrain Syndrome?

Neuro-ophthalmology Illustrated Chapter 13 Diplopia 9 – Internuclear & Supranuclear Lesions

January 22, 2020 By

Questions:
115. A patient has a deficit of adduction of the one eye, nystagmus of the fellow abducting eye, skew deviation and the adduction deficit is overcome with convergence. What condition is present?
116. A patient has a deficit of adduction of the one eye, nystagmus of the fellow abducting eye, skew deviation and the adduction deficit is overcome with convergence. Where is the lesion?
117. What are 4 findings of a unilateral internuclear ophthalmoplegia?
118. A patient has a deficit of adduction of both eyes, nystagmus of the fellow abducting eye, exotropia, and loss of convergence. What condition is present?
119. Where is the lesion located in wall-eyed bilateral internuclear ophthalmoplegia (WEBINO)?
120. A patient has the following findings: a gaze palsy to one side, and on attempted gaze to the opposite side impaired adduction and nystagmus of the abducting eye. In addition, the patient has a facial palsy on the side with the gaze palsy. What syndrome is present?
121. Where is the lesion in the One-and-a-Half Syndrome?
122. What are 2 common causes of isolated internuclear ophthalmoplegia?
123. What conditions may mimic an isolated internuclear ophthalmoplegia?
124. What conditions may mimic the one-and-a-half syndrome?

Neuro-ophthalmology Illustrated Chapter 13 Diplopia 8 – Miller Fisher, Guillain-Barré & Botulism

January 15, 2020 By

Questions:
104. What diagnoses should be considered in all cases of new-onset constant or transient ptosis and/or diplopia?
105. What syndromes have ataxia, areflexia, and ophthalmoplegia?
106. What is the Miller Fisher syndrome?
107. What is the Guillain-Barré syndrome?
108. What is the difference between the Miller Fisher and the Guillain-Barré syndromes?
109. When should the Wernicke encephalopathy be considered?
110. What is Wernicke encephalopathy?
111. What does botulism do to the pupils and what are its other symptoms?
112. What is the infectious agent of botulism?
113. What is the mechanism of botulism toxin?
114. What is the treatment for botulism?

Neuro-ophthalmology Illustrated Chapter 13 Diplopia 7 – Lesion Involves Multiple Cranial Nerves

January 8, 2020 By

Questions:
92. What signs when associated with lesions causing unilateral or bilateral ophthalmoplegia may help localize the lesion?
93. What are the findings of the orbital apex syndrome?
94. Do brainstem lesions often produce multiple cranial nerve palsies?
95. What are 4 systemic disorders that affect the cranial nerves?
96. What condition should be considered in patients with unilateral or bilateral ophthalmoplegia and normal pupils presumed to result from multiple cranial neuropathies?
97. What is the likely cause of a painful orbital apex syndrome in a diabetic patient?
98. Do normal orbital imaging studies rule out an orbital apex lesion?
99. Does the orbital apex syndrome involve the second division of the fifth nerve?
100. What are the findings of the cavernous sinus syndrome?
101. If a cavernous sinus syndrome includes venous hypertension (carotid-cavernous fistula or cavernous sinus thrombosis), what additional findings may be present?
102. Which cranial nerves are enclosed in the lateral wall of the cavernous sinus?
103. Why do cavernous carotid artery aneurysms often present with an isolated sixth nerve palsy?

Neuro-ophthalmology Illustrated Chapter 13 Diplopia 6 – 3rd Nerve Palsy

December 18, 2019 By

Questions:
71. How are 3rd nerve dysfunctions classified?
72. What is the definition of a partial 3rd nerve palsy?
73. What are the two categories of complete 3rd nerve palsies?
74. What is meant by “a pupil-sparing 3rd nerve palsy”?
75. What tests should be done when a patient over age 50 presents with an isolated incomplete 3rd nerve palsy and the pupil is involved?
76. What should be done when a patient over age 50 presents with an isolated complete 3rd nerve palsy and the pupil is Not involved?
77. What should be done when a patient over age 50 presents with an isolated complete 3rd nerve palsy, the pupil is Not involved; normal blood glucose, CBC, platelets, ESR, and CRP is followed daily and develops pupillary involvement?
78. What is the most common cause of an isolated “pupil-sparing 3rd nerve palsy”?
79. Are microvascular 3rd nerve palsies painful?
80. What should be ruled-out when making the diagnosis of a microvascular complete 3rd nerve palsy with pupil-sparing in a patient over 50?
81. What in addition to cranial arteritis should be considered when making the diagnosis of a microvascular pupil complete 3rd nerve palsy with pupil-sparing?
82. How long does it usually take for a microvascular 3rd nerve palsy to resolve?
83. If a complete 3rd nerve palsy with pupil-sparing thought to be of microvascular origin does not clear in 4 months what should be done?
84. What test should be done in a patient under age 50 who presents with an isolated 3rd nerve palsy with or without pupillary involvement?
85. Should the pupils of a patient with an acute 3rd nerve palsy with “pupil sparing” be dilated to complete the eye exam?
86. A patient without a history of trauma has signs of aberrant regeneration of the 3rd nerve. What should be ruled-out?
87. What are the symptoms of pituitary apoplexy?
88. What are the findings when there is a unilateral lesion of the entire 3rd nerve nucleus?
89. Why does a complete unilateral nuclear 3rd nerve palsy have bilateral ptosis?
90. Why does a complete unilateral nuclear 3rd nerve palsy have bilateral elevation deficits?
91. What are the findings of a unilateral lesion of the 3rd nerve fascicle?

Neuro-ophthalmology Illustrated Chapter 13 – Diplopia 5 – 4th Nerve Palsy

December 11, 2019 By

Questions:
61. What are 6 characteristics of a 4th nerve palsy?
62. When a patient has a 3rd nerve palsy and the eye cannot adduct, how can the function of the ipsilateral 4th nerve shown to be present?
63. What 5 other conditions should be considered when the patient has the findings of a 4th nerve palsy?
64. A patient has a 4th nerve lesion associated with a contralateral Horner syndrome, where does this localize the lesion?
65. A microvascular 4th nerve palsy is suspected because the 60-year-old patient has diabetes, hypertension, and hyperlipidemia what tests should be ordered?
66. A presumed microvascular 4th nerve palsy in a 60-year-old patient with diabetes, hypertension, and hyperlipidemia has not resolved within 3-6 months, what tests should be ordered?
67. A 40-year-old patient appears to have a 4th nerve functional defect. What diagnoses in addition to 4th nerve palsy should be considered?
68. A 60-year-old patient presents with intermittent vertical diplopia with the findings of a 4th nerve palsy on the 3-step-test. What in addition to an acquired 4th nerve palsy, restriction, myasthenia, Wernicke encephalopathy, and cranial arteritis should be considered? 
69. Are congenital fourth cranial nerve palsies common?
70. What are 3 findings characteristic of a congenital a decompensated congenital 4th nerve palsy?

Neuro-ophthalmology Illustrated Chapter 13 – Diplopia 3 – Binocular Diplopia

November 27, 2019 By

Questions:
29. In a comatose patient, you observe dysconjugate horizontal eye movements when the head is rotated from side to side. What does this suggest?
30. What is the most common cause of unilateral proptosis?
31. What is the most common cause of bilateral proptosis?
32. Which is the most commonly involved extraocular muscle in thyroid eye disease?
33. What is the differential diagnosis of enlarged extraocular muscles?
34. On CT or MRI, which condition spares the insertions of the extraocular muscles, thyroid eye disease or idiopathic orbital inflammation (orbital pseudotumor)?
35. What 4 features differentiate idiopathic orbital inflammation (orbital pseudotumor) from thyroid eye disease?
36. When should a biopsy be done in a patient with presumed “myositis”
37. What tests should be done in all patients over age 50 with transient or permanent diplopia?
38. What is the Silent Sinus Syndrome?
39. What is the Kearns-Sayre syndrome?
40. What are 5 mitochondrial diseases that can have ophthalmoplegia?
41. What are the features of Myotonic Dystrophy?
42. What are 5 features of Oculopharyngeal Dystrophy?
43. What 3 conditions other than paresis or restriction should be considered in any adult with new-onset transient or permanent ocular misalignment?
44. What may induce myasthenia gravis or make it worse?
45. What is the mechanism of action of edrophonium?
46. What are the side effects of the Tensilon test?
47. What does the development of lid retraction in a patient with Myasthenia suggest?

Neuro-ophthalmology Illustrated Chapter 13 – Diplopia 1 – Basics

November 13, 2019 By

Questions:
1. What 5 anatomical components involved in eye movement can cause binocular diplopia?
2. What holds the image steady during brief head movements?
3. What holds the image steady during sustained head movements?
4. What is Sherrington’s law?
5. What is Hering’s Law?
6. What 2 processes cause most incomitant strabismus?
7. What is the primary deviation in incomitant strabismus?
8. What is the secondary deviation in incomitant strabismus?
9. Is the primary or secondary deviation larger in incomitant strabismus?
10. Does a phoria or a tropia have more value in localizing the defect in a patient with new-onset binocular diplopia?
11. What is the difference between the terms “ocular motor” and “oculomotor”?
12. What 3 techniques can help determine if an ocular misalignment is due to a restriction or paresis?

Neuro-ophthalmology Illustrated Chapter 12 – The Pupil 4

October 30, 2019 By

Questions:
32. What are ocular disorders that keep a large pupil from constricting?
33. How does one test for pharmacologic mydriasis from topical agents?
34. What are two conditions that cause mydriasis via the parasympathetic nervous system?
35. What are the clinical symptoms and signs of Adie tonic pupil?
36. What explains the light-near dissociation classically found in Adie tonic pupil syndrome?
37. What topical drop is used to confirm the presence of Adie pupil syndrome?
38. Is isolated mydriasis likely to be caused by a third nerve paresis?
39. What may happen to the size of the pupil over time in the Adie syndrome?
40. Do all third nerve paresis have pupillary involvement?
41. What may the workup for an isolated third nerve palsy with mydriasis reveal?

Neuro-ophthalmology Illustrated Chapter 12 – The Pupil 3

October 23, 2019 By

Questions:
13. What are the characteristics of physiologic anisocoria?
14. What are the ocular causes of anisocoria?
15. What are the signs of Horner Syndrome?
16. What neurologic symptoms and signs can be associated with Horner syndrome?
17. Which eye drops can be used to establish the diagnosis of Horner syndrome?
18. What is the mechanism of action of cocaine when used to test Horner syndrome?
19. What is observed when testing for Horner syndrome with cocaine?
20. What is the mechanism of action of apraclonidine when used to test Horner syndrome?
21. What is observed when testing for Horner syndrome with apraclonidine?
22. What eye drop is used to localize which order neuron is involved in Horner syndrome?
23. What is the mechanism of hydroxyamphetamine when used to test Horner syndrome?
24. What is observed when hydroxyamphetamine is used to test Horner syndrome?
25. What is the classic cause of a first-order neuron Horner syndrome?
26. What does the combination of an ipsilateral Horner syndrome (first-order) and contralateral superior oblique palsy (fourth nerve palsy) suggest?
27. What does the combination of an ipsilateral Horner syndrome (third-order) and an abducens paresis (sixth nerve palsy) suggest?
28. What should be the presumed cause of an acute painful Horner syndrome?
29. If the localization of a Horner syndrome is unknown what imaging tests should be done?
30. In a young child with an isolated Horner syndrome, a workup should be done for what condition?
31. What tests should be done in a child with a Horner syndrome without a surgical history to explain it?