Transcript Grand Rounds

Re-Double
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Ron Teed, M.D.
 12 January 2007
 Vanderbilt Eye Institute
Alfred Bielschowsky
Patient History I
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cc: vertical binocular diplopia
 63 yo male with 4 week history of diplopia;
first intermittent, then constant
 Worse in right gaze
 No antecedent trauma, CVA, craniofacial
surgery
 No history strabismus
 No history thyroid disease, myasthenia
Patient History II
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POH: none
 PMH: DJD, hernias
 Meds: ibuprofen
 FH: no ocular disease
 SH: tobacco use in past
 ROS: no dizziness, weakness, HA, jaw
claudication, fatigue, numbness, paresthesia
Differential Diagnosis of
Vertical Binocular Diplopia
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Superior Oblique Palsy
Thyroid Ophthalmopathy
Myasthenia Gravis
Brown Syndrome
Orbital fracture with entrapment
Cyclovertical paresis or overaction
Skew Deviation/Ocular Tilt
Dissociated Vertical Deviation
Exam I
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General: alert and oriented; no anomalous head
posture; no nystagmus
BCVA 20/20, 20/20
Fields: Full OU
Tonometry: 15,14
Pupils: no rAPD, no anisocoria
External Exam: no proptosis, ptosis, lid retraction;
no fatigue
SLE: unremarkable, quiet eyes
DFE: unremarkable, no optic nerve edema/pallor
Versions
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Measurements
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8 LHT
5 LHT
3 LHT
8 LHT
4 LHT
10 LHT
Additional Clinical
Tests
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“fourth step”
– Measurement of ocular torsion
– Double Maddox Rod: 5° excylotorsion OS
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Vertical Fusional Amplitudes
- Large amplitudes suggest congenital etiology
- 3 prism diopters
Superior Oblique Palsy
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Clinical diagnosis from Three-step test
 What do we do now?
Superior Oblique Palsy
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Determine if this is a ISOLATED CN IV
palsy
No neurological symptoms on history
 Cursory neurological exam unremarkable
Isolated Superior Oblique Palsy
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Most common etiologies are congenital and
traumatic
 Also vascular; less commonly tumor,
demyelinating
 In absence of other neurological symptoms
and presence of vascular risk factors,
reasonable to observe
Isolated Superior Oblique Palsy:
Management Plan
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Our patient did not have obvious vascular
risk factors other than age
– No known HTN, hyperlipidemia, DM
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Patient was observed
– To return if diplopia changes, ptosis develops,
or he has any numbness, weakness,
paresthesias, disorientation, unsteadiness,
vertigo, headache
Patient Follow-up
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Pt returns 8 weeks later
 “double vision is a bit better…”
 “…ever since I had the radiation treatment”
Follow Up Exam
0
5 LHT
2 LHT
5 LHT
4 LHT
10 LHT
DMR: 5° excylotorsion OS
8 LHT
More History
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A few weeks after first visit, pt developed
unsteady gait, disequilibrium associated
with flank pain
 No longer isolated fourth nerve palsy
– Measurements no longer map to superior
oblique palsy
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Now what do we think is going on?
 Now what would we do?
Imaging
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CT
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MRI
Vertical Diplopia and Pontine
Mass
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Does this lesion explain vertical diplopia?
– Lesion to CN IV nucleus or nerve?
– Lesion to other pathways encoding vertical
gaze?
Back to the original
presentation
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Was it right to observe an apparent isolated CN IV
palsy?
– Texts, review articles suggest that observation is
acceptable, particularly if the palsy is suspected to be
congenital, traumatic, or there is a vascular risk factor
– Spontaneous resolution of CN IV palsy occurs within 3
months in 50-95% of patients (better in presumed
vascular etiology)
– Up to one third have undetermined etiology
Watching the CN IV palsy
“evaluation for an isolated fourth nerve palsy
usually yields little information... Older patients
should be followed” (BCS, Neuro-ophthalmology)
 “MRI…for all patients younger than 45 years with
no definite history of significant head trauma, and
patients aged 45 to 55 years with no vasculopathic
risk factors or trauma” (Wills Eye Manual)
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The Evidence
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Multiple case series of presumed isolated CN IV
palsies
– No documented tumors as etiology (Keane 1993: 0/81)
– But may fail to adequately confirm true isolation or
confirm true CN IV palsy
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Lee et al (1998) reviewed cost-effectiveness of
imaging
– No need to image suspected congenital, traumatic, or
vasculopathic palsies
The Rebuttal
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A few case reports of isolated CN IV palsies from
brainstem strokes
 Feinberg and Newman (1999): 6/68 isolated CN
IV palsies related to trochlear nerve Schwannoma
 Scattered other reports of isolated CN IV palsy
from other conditions:
– Pituitary macroadenoma
– MS, polycythemia rubra
So what do we do?
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What is your level of comfort?
 How good is your neurological exam?
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Reasonable and cost-effective to observe,
but you may miss an important lesion
Take Home Points
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Determine if an apparent superior oblique
palsy is truly isolated
 If isolated, it may be reasonable to observe
 Understand basic anatomy of the pathways
encoding vertical eye movements
References
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Brodsky MC, Donahue SP, Vaphiades M, and Brandt T (2006). Skew
Deviation Revisited. Survey of Ophthalmology. 51:105-128.
Donahue SP, Lavin PJM, and Hamed LM (1999). Tonic Ocular Tilt Reaction
simulating a superior oblique palsy. Archives of Ophthalmology. 117:347-352.
Feinberg AS and Newman NJ (1999) Scwannoma in patients with isolated
unilateral trochlear nerve palsy. American Journal of Ophthalmology 127:18388.
Keane JR (1993). Fourth nerve palsy: Historical review and study of 215
inpatients. Neurology. 43:2439-2443.
Kusher BJ (1989). Errors in the Three-Step Test in the Diagnosis of Vertical
Strabismus. Ophthalmology. 96:127-132.
Lee AG, Hayman LA, Beaver HA, et al (1999). A guide to the evaluation of
fourth cranial nerve palsies. Strabismus 6(4): 191-200.
Petermann SH and Newman NJ (1999). Pituitary Macroadenoma manifesting
as an isolated fourth nerve palsy. American Journal of Ophthalmology
127:235-6.
Thomke F and Ringle K (1999). Isolated superior oblique palsies with
brainstem lesions. Neurology. 53(5):1126-27.
CT
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T1 MRI
T2 MRI
Axial
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CN IV nucleus
Otolithic Pathways