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

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 – 4 – 6th Nerve Palsy

Questions:
47. Which cranial nerve passes through the Dorello canal beneath the petroclinoid (Gruber) ligament?
48. Where is the nucleus for the 6th cranial nerve located?
49. What are the clinical findings of a unilateral 6th nerve nuclear lesion?
50. Why does a unilateral nuclear 6th nerve palsy cause an ipsilateral horizontal gaze palsy?
51. Why is a unilateral 6th nerve palsy often accompanied by an ipsilateral 7th nerve palsy?
52. Where is the lesion in a patient with an ipsilateral Horner syndrome and 6th nerve palsy?
53. Where is the lesion in a patient with an ipsilateral Horner syndrome, 6th nerve palsy associated with 3rd nerve, 4th nerve, V1 and V2 deficits?
54. A microvascular 6th nerve palsy is suspected because the 60-year-old patient has diabetes, hypertension, and hyperlipidemia what tests should be done?
55. A presumed microvascular 6th nerve palsy is suspected in the 60-year-old patient with diabetes, hypertension and hyperlipidemia has not resolved within 3-6 months, what test should be ordered?
56. What explains the findings of Duane syndrome?
57. What are the findings of Duane syndrome?
58. Are systemic associations common in Duane syndrome?
59. What is Möbius syndrome?
60. What should be done in a patient with bilateral 6th nerve palsies and a normal MRI?

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

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 2 – Assessment

Questions:
13. How is Bell’s phenomenon checked in normal patients?
14. What is the localization of the lesion in a patient when Bell’s phenomenon is preserved despite an upgaze paresis?
15. What is the localizing value of abnormal eye movements that are overcome by oculocephalic maneuvers?
16. What symptom is usually noted by a patient with convergence insufficiency?
17. A patient presents with a history of the onset of diplopia 3 weeks ago. What should be the first characteristic of the diplopia determined?
18. Your exam confirms that a patient has binocular diplopia, but on exam the extraocular movements appear full. What must be present?
19. Your exam confirms that a patient has patient binocular diplopia, but on exam the extraocular movements appear full. What tests will be helpful in demonstrating the misalignment?
20. What will the cross-cover test detect that the cover-uncover test will not detect?
21. When is a phoria pathologic and not physiologic?
22. Is the 3-step-test useful in horizontal or vertical binocular diplopia?
23. What reflex is involved in the third step of the 3-step-test?
24. With the red Maddox rod placed between a light source and the eye, what does the eye see?
25. Why would one perform the double Maddox Rod test?
26. When are the Hirschberg and Krimsky tests useful?
27. How is the Hirschberg test performed?
28. How is the Krimsky test performed?

Neuro-ophthalmology Illustrated Chapter 13 – Diplopia 1 – Basics

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 5

Questions:
42. What is a tadpole pupil?
43. What are 6 causes of light-near dissociation?
44. What is the Argyll Robertson pupil and where is its lesion located
45. What is the mechanism in light-near dissociation due to Argyll Robertson pupils?
46. Where is the lesion in a patient with light-near dissociation due to Adie tonic pupil?
47. What is the mechanism in light-near dissociation due to aberrant regeneration of the 3rd nerve?
48. What is the mechanism in light-near dissociation due to severe vision loss?
49. What is the mechanism in light-near dissociation due to laser panretinal photocoagulation or cryotherapy?
50. Where is the lesion in a patient with light-near dissociation due to peripheral neuropathy?

Neuro-ophthalmology Illustrated Chapter 12 – The Pupil 4

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

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?

Neuro-ophthalmology Illustrated Chapter 12 – The Pupil 2

Questions:
 
5. Which order neuron is involved when the Horner syndrome is caused by a tumor in the apex of a lung?
  6. Do patients with a third-order Horner syndrome usually have anhidrosis?
  7. What neurotransmitter is released at the neuromuscular junction that results in pupillary constriction?
  8. What neurotransmitter is released at the neuromuscular junction that results in pupillary dilation?
  9. Why do lesions of the geniculate nucleus, the optic radiations, or the visual cortex not affect pupillary size or pupillary reactivity?
10. What is the course of the parasympathetic fibers for pupillary constriction from the Edinger-Westphal nucleus to the ciliary ganglion?
11. What is the ratio of postganglionic parasympathetic fibers that innervate the ciliary muscle to those that innervate the pupillary sphincter muscle?
12. What specific steps should be followed in examining a patient with anisocoria?

____________________________________________________

Neuro-ophthalmology Illustrated Chapter 12 – The Pupil 1

Questions:
1. When examining the pupils, what 6 items should be recorded?
2. Does a relative afferent pupillary defect cause anisocoria?
3. If there is no relative afferent pupillary defect in a patient is suspected of having optic neuropathy (regardless of the cause) does that rule-out this diagnosis?
4. If a patient has severe bilateral optic neuropathy will the pupils respond to near stimuli?