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Old 11-11-2013
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Default Myasthenia Gravis vs Multiple Sclerosis

Can someone please explain this for me:

A female in her young 20s has acute onset diplopia. She has had blurry vision 6 months and 2 years ago with associated color vision loss and eye pain with movement. There is slow adduction of the left eye with right lateral gaze, while convergence is normal. What is the cause of pt.'s diplopia?

Is it multiple sclerosis because of the associated eye pain and loss of color vision? If we were to get rid of those two, then would be MG?
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Old 11-11-2013
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I think it is multiple sclerosis because it describes internuclear ophthalmoplegia which is caused by medial longitudinal fasciculus lesion

MG also causes muscle fatigue and it does not cause loss of color vision it mainly causes ptosis

I believe also multiple sclerosis should have at least 2 syndromes separated in time and place

like left leg weakness 2 years ago and diplopia now

but I would still choose multiple sclerosis because the stem describes internuclear ophthalmoplegia
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Old 11-12-2013
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Quote:
Originally Posted by taher View Post
I think it is multiple sclerosis because it describes internuclear ophthalmoplegia which is caused by medial longitudinal fasciculus lesion

MG also causes muscle fatigue and it does not cause loss of color vision it mainly causes ptosis

I believe also multiple sclerosis should have at least 2 syndromes separated in time and place

like left leg weakness 2 years ago and diplopia now

but I would still choose multiple sclerosis because the stem describes internuclear ophthalmoplegia

Thank you! So I guess its the fact that there's nystagmus and the sensory loss that gives it away? That makes sense!
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Old 11-12-2013
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Quote:
Originally Posted by winter View Post
Thank you! So I guess its the fact that there's nystagmus and the sensory loss that gives it away? That makes sense!
the time thing is also big...it happened 6 months back, after happening 2 years ago. Thats a dead ringer for MS.
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Old 11-13-2013
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Originally Posted by CisternaChyli View Post
the time thing is also big...it happened 6 months back, after happening 2 years ago. Thats a dead ringer for MS.
Thank you! So normally MS occurs on and off, right?
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Old 11-13-2013
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1.History of Intermittent attack neurological episode

2.Period of well being between this two period

3.Retrobulbar neuritis deducing from (painful eye movement + blurry vision) unless otherwise excluded

4. Sex preponderance

5.Loss of color vision which never occurs in MG

6. Last but the most important indicating factor here is Internuclear Opthalmoplegia from lesion in MLF resulting in ataxic nystagmus, with convergence reaction normal
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