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31 Cards in this Set
- Front
- Back
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List causes of Monocular diplopia
Which improve with pinhole |
Uncorrected refractive error
Cataract Corneal or Iris abnormalities Dislocated lens |
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List causes of Monocular diplopia
Which don't improve with pinhole |
Cerebral polyopia (multiple images)
Palinopsia (visual preservation in time) Psychogenic (diagnosis of exclusion) |
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3 causes of Oscillopsia
(objects in the visual field appear to oscillate.) |
Ocular neuromyotonia
Superior oblique myokymia Nystagmus |
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What is it?
Rare disorder of episodic diplopia Involuntary contraction of EOM Prior radiation therapy to sellar or parasellar region |
Ocular neuromyotonia
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What is it?
Vertical or torsional diplopia Bursts of rotary, small amplitude oscillations Intorsional movements |
Superior oblique myokymia
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Causes of Binocular diplopia
(Incomitant ocular misalignment) |
Isolated cranial nerve 3, 4, 6 palsy
Graves’ or other muscle disease Myasthenia Gravis or other NMJ disease Miller Fisher variant (demyelinating) Skew deviation or ocular tilt reaction Parinaud syndrome Internuclear ophthalmoplegia |
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Causes of Binocular diplopia
(Comitant ocular misalignment ) |
Decompensated phoria (lose fusional ability with a preexisting ocular misalignment)
Foveal displacement syndrome (fovea of one eye displaced by retinal disease) Metamorphopsia from retinal disease Convergence insuffiency (convergence weakness without other neurologic signs) |
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Cause of CN3 palsy
a) aneurysm b) vasculopathic c) trauma |
a) aneurysm or
b) vasculopathic |
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Cause of CN4 palsy
a) aneurysm b) vasculopathic c) trauma |
c) trauma
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Cause of CN6 palsy
a) aneurysm b) vasculopathic c) trauma |
b) vasculopathic
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90% of posterior communicating artery aneurysms present with a ___ nerve palsy prior to rupture
(Worst headache of life) |
3rd
(51% fatality rate if aneurysmal rupture) |
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What type of 3rd nerve palsy?
Microangiopathy from diabetes and hypertension Generally spare the pupil 8-15% of aneurysmal compression may initially spare the pupil |
Vasculopathic
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What happens when you test a Horner's syndrome with cocaine?
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Cocaine fails to dilate abnormal pupil
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What happens when you test a Horner's syndrome with Paredrine?
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Paredrine dilates preganglionic, fails to dilate post ganglionic
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What happens when you test a Horner's syndrome with Apraclonidine?
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Apraclonidine reverses anisocoria (room light on)
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What kind of pupil?
Parasympathetic system Larger is involved pupil Abnormal light reaction More apparent in bright lt (abn pupil does not constrict, nl pupil does) Normal near response (light near dissociation) |
Adie’s pupil
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What does Pilocarpine's role in Adie’s Pupil Testing
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Pupillary constriction with pilocarpine is diagnostic
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What conditions include anisocoria?
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Horner’s syndrome
Adie’s pupil Structural damage Oculomoter nerve palsy Pharmacologic |
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MC eye muscles enlarged in hyperthyroidism
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Inferior rectus
Medial rectus |
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What's the problem?
Ptosis in 75%, diplopia not following a set pattern Mimic many ocular motility disorders Worse with fatigue, as the day progresses Better in morning or after sleep If systemic, may be life threatening Associated with thymoma in 10% Dysthyroidism association in 5% |
Myasthenia Gravis
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What's the syndrome?
Ophthalmoplegia, severe ataxia and loss of tendon reflexes Occurs in 5% of patients with Guillain Barre syndrome Ophthalmoplegia is complete with mydriasis in 48.9% Anisocoria or normal pupils Involvement of cranial nerves 1, 5, 7-12 reported CSF shows albuminocytologic dissociation MRI is typically normal |
Miller Fisher Syndrome
(pictures show pt who can only look up and straight ahead) |
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What is skew deviation
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Hypertropia frequently fixed for all directions of gaze (comitant) or variable in all directions of gaze (incomitant) yet not referable to a cranial nerve or local mechanical orbital lesion
May occur with any lesion of the brainstem or cerebellum and the eye on the side of the lesion is usually the hypertropic one |
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Describe "ocular tilt reaction"
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Consists of a skew deviation, bilateral ocular torsion, head tilt toward the side of the lower eye
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ocular tilt reaction is frequently misdiagnosed as what?
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Frequently misdiagnosed as superior oblique palsy but can distinguish from SO palsy by the characteristic intorsion of the hypertropic eye and extorsion of the hypotropic eye, as opposed to extorsion of the hypertropic eye, as in superior oblique palsy
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What's the syndrome?
Dorsal midbrain syndrome (pineal tumor) Skew deviation Square-wave jerks Impaired up gaze Convergence retraction nystagmus (OKN drum downward) Convergence spasm Lid retraction (Collier’s sign) Light-near dissociation |
Parinaud syndrome
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What is the problem?
Medial longitudinal fasciculus lesion Weak adduction ipsilateral to lesion Adducting saccades slow Abduction nystagmus contralateral Common in MS, especially if bilateral INO WEBINO (wall-eyes bilateral INO) in ischemia |
Internuclear ophthalmoplegia
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What's the problem?
Ophthalmoplegia, ataxia, global confusion Horizontal nystagmus and abduction deficits Apathy, inattention, confusion and coma Only 1/3 have the complete triad |
Wernicke Encephalopathy
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Describe Korsakoff Psychosis
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Antegrade and retrograde amnesia
Gaps in memory filled in by confabulating information readily recalled at the moment 20-25% do not recover memory |
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MRI of Wernicke
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Increased T-2 signal paraventricular regions of the thalamus and periaqueductal regions and enhancement of the mamillary bodies (Wernicke)
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MRI of Korsakoff
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Atrophy of thalamic nuclei, mamillary bodies, cerebellum and cerebral hemispheres (Korsakoff)
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Treatment of Wernicke's
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As little as 2 mg of Thiamine may be enough to reverse ocular symptoms (improves in 6 hrs)
Thiamine prior to glucose solution Thiamine 100 mg IV until normal diet |
