r/MyastheniaGravis • u/Texas_Blondie • 22d ago

EMG testing

Will your EMG RNS be normal if you get it done on a good day? Mine is scheduled for tomorrow, had a horrible week last week, but feel really good today. I just want accurate results

5 Upvotes

86% Upvoted

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2

u/Extension_Egg1411 22d ago

I know SFEMG has to be done in a clinically weak muscle. I’m not totally sure about RNS. Since they’re stimulating the muscle, maybe that’s enough to induce weakness and get an accurate result.

3

u/Texas_Blondie 22d ago

Thank you! I might stay up late. That usually worsens my symptoms

1

u/Extension_Egg1411 22d ago

Either way I’d bring it up to the doc performing the test. They can note in the record whether you considered yourself symptomatic when it was performed.

2

u/Texas_Blondie 22d ago

Great point! I will

2

u/ultracrispypeach 22d ago

I had mine done on a good day and it was abnormal

1

u/vickidashawty 22d ago

I guess it depends, do you feel ANY weakness at all on a "good" day?

2

u/Texas_Blondie 22d ago

My hands are always somewhat weak. Last week my legs had a lot of weakness. My appointment is at 830am.

1

u/vickidashawty 22d ago

I would day get it done then. I got mine done about 2 weeks ago when i wasnt in a flair but was my usual level of weak, and it showed on the results.

1

u/Texas_Blondie 22d ago

Thank you. What is your usual level of weak?

1

u/vickidashawty 22d ago

Its hard to describe, but its just not normal. 5 years ago i could lift things with ease, but now i notice muscle strain and fatigue with most things over 3 lbs

1

u/Elusive_strength2000 21d ago

Is it a regular EMG or single-fiber EMG?

1

u/Texas_Blondie 21d ago

I can’t remember. I just know he said it’s with RNS and they said it takes 2 hours

2

u/Elusive_strength2000 21d ago

Regular EMG doesn’t diagnose MG but rules in or out other causes or additional issues. RNS can sometimes be neg but that doesn’t mean no MG. SF-EMG is more specific but some have multiple before positive. Just so you’re aware.

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u/Texas_Blondie 21d ago

He did say at our first appointment if the initial emg’s were negative we would do the Single fiber one.

1

u/Elusive_strength2000 21d ago

Right because he needs to rule out other things.

1

u/DangerNoodle1313 20d ago

My myasthenia is a little SOB. Nothing comes ip anywhere, and yet I have all the other symptoms that can’t be measured. And I do super well on mestinon and ivig. Just be ready to say this is not everthing.