AANEM Connect

52 yo female s/p chemo for breast ca 2017. Bilateral LE markedly absent PP, vibration, LT distal to her shins bilaterally.  High arches and hammer toes, thin ankles, calfs not atrophied. MMT 5/5 bilateral LE, but weak heel raise bilaterally.

Bilateral LE tibial and fibular motor responses were normal, but elicited only upon increasing the PW to 200-700 us, and 100 mA (patient insensate so not painful). Bilateral superficial peroneal and sural responses were absent, H-reflexes absent, fibular F wave absent. Tibial F waves normal.

Needle EMG was normal.

What is the significance, if any, of the requirement of strong stimulation to elicite a normal motor response in this setting?

Thank you,
Robert

Dear colleagues,

I've recently seen a patient who's NCS results like this: increased CMAP duration in all elicited nerves with reduced CMAP amplitude significantly, but without conduction block, slow CV, prolonged distal motor latency or F-waves (mild slow CV or prolonged late responses were observed, but not compatible to demyelination criteria). 

That also was not temporal dispersion. All segment was increased in CMAP duration. (for example, R median 10.2 / 9.6 / 10.5 ms, R ulnar 12.3 / 12.7 / 12.5 / 13.0 ms, R tibial 24.5 / 23.9 ms , and so on.)

Is it reasonable that this patient is under demyelinating process of neuropathy? or else?

For your information, He is 50-yo and found to be paraparetic after prolonged sedation and tracheostomy (over 1 week) in ICU care. I would suspected critical illness polyneuropathy but the NCS's was a little bit confusing. 

Thanks in advance.

 

Hello,

I have a 44 year old male with no PMH who was referred to rule out radiculopathy.  His MRI demonstrates foraminal narrowing on the opposite leg, the left, but nothing notable on the right.

He definitely was enhancing his discomfort because of the continued pain in spite of pain management and multiple doctors attempting management with limited success.

His NCV demonstrated delayed surals in the ball park of 5.2.  He had absent H reflexes bilaterally.  The remainder of the sensory and motor NCV was WNL.  His EMG was within normal.

I am just wondering if there is a diagnosis or further work up that would be warranted from this?

Thank you in advance.

Female in 30s with non-specific fatigue but normal neurological examination and nerve conduction studies. Normal CK. Normal thyroid function. No objective weakness or clinical muscle fatiguability. No bulbar or ocular symptoms. Several very short (<3ms) MUAPs in triceps and deltoid, though not small and didn't seem to have early recruitment.

Is this definitely mild myopathy or could it be a normal finding?

Hello,

I am part of a group practice. Some of the doctors have been sending patient for bilateral studies but the patinet only has symptoms in 1 limb. The way I trained we focused on performing a few NCS or needle sticks to make the diagnosis or rule something out. 

I requested calrification on what they were looking for and was told that patient with chornic pain and pateint with neuropathy should always have bilateral studies beacuse this is what  previous EMG clinic has told them. 

There certanly are cases where you need to study the other limb for referance or determine a more systemic proccess such as neuropathy. However , I have some concerns especilly when sent for Bilateral UE studies and 1 limb has no symptoms.

has anyone else run into this and if so how did you handle it. 

I recently saw a lady very early on (11 days) from onset of neck pain, arm pain, paresthesias and subjective weakness of the hand. I saw her for EMG at the request of her PCP due to travel and timing issues. Clearly this is not the ideal time from for EDX evaluation of radiculopathy. Her ulnar CMAP to ADM/FDI was reduced (~3.5 mv) with normal median CMAP, normal median, ulnar, radial and MABC/LABC sensory responses. No conduction block or slowing at the elbow. Needle examination showed mildly reduced recruitment in Extensor Indicis, triceps and maybe ADM. Normal paraspinals. I suspect cervical radiculopathy, possibly in C8 distribution. Has anyone seen this presentation and type of finding before? Any thoughts about the process involved?

We need a ground electrode to provide a safe path for leakage current away from our patients. But why, given that we are using differential amplifiers with very high CMRR's, is the 60 hz artifact so overwhelming when the ground electrode is disconnected. You would think that the effects of extraneous 60 hz interference would be equal to the two pre amplifier inputs and thus cancel.

I had a patient present the other day with back and buttocks pain for EMG. The patient was in her 30's. symptoms had been going on for almost a year. no weakness. no complaints of numbness or tingling in her toes or feet. NO radiating symptoms intot the leg. normal examination for strenth and sensation (light touch and vibration). no family hx of neuropathy. 

Her nerve conduction studies and needle exam were normal with exception of inability to otbain sural responses bilaterally. I moved the electrode 3 times on each side. I rolled across the calf with changes ,in stimulator alignement for several minutes and could not find anything that appeared consistant. 

Can this ever be a normal varient or is this signsof neuropathy that is not symptomsatic yet? 

April Yuki

Dear Colleagues, I was hoping for some advice on this one...

I was referred a 70 yo non-diabetic man by a neuro-ophthalmologist for vertical diplopia who in the course of his workup was found to have positive AChR antibodies. The patient woke-up with isolated fixed binocular diplopia, has had no fluctuation since onset, and has no ptosis, fatiguability, or generalized weakness on exam. MRI of the brain was normal. Repeat MRI and AChR antibodies two months later were unchanged (normal and positive, respectively). No response to pyridostigmine. Interestingly, his brother has symptomatic MG with positive antibodies, diagnosed >20 years ago. 

Given the history and exam, the working diagnosis is an MRI-negative posterior circulation stroke. But what to do about the antibodies? Pre-symptomatic MG? Epiphenomenon of underlying autoimmunity? 

In  a patient with a severe inherited peripheral neuropathy- if the distal CMAPs (and SNAPs) are absent from the lower and upper limb nerves - how do we define whether it is predominantly demyelinating or only pure axon degenerative? 
We could think of the following :
1.Recording over the FCR /FCU muscle and stimulating the Median/Ulnar nerve at the elbow and mid arm : any data available for defining when it should be called demyelinating?
2. R1 & R2 components of  blink reflex if prolonged is it demyelinating ?
Could not find any defined criteria for this -would appreciate inputs please 

Second question from the same patient （brachial plexopathy)

say, the thumb is in C6 dermatome. Does it mean all C6 sensory fibers go to this dermatomes and only C6 fibers go to this dermatomes? 

this patient has completely normal median SNAP amplitude from the thumb ( comparable to the normal side) but completely unobtainable from the long finger ( including mid palm stim). 

This is a real question. When there are two roots innervating a muscle and there is complete axonopathy to one of the two roots but not the other, do the axons from the unaffected root reinnervate (via collateral sprouting) the muscle fibers originally innervated by the other root? This question arose from seeing a patient with brachial plexopathy today. 

I thought of this waveform after the recent posting. I made this video in 2012 for my residents to drive home the same point as the last one.  Enjoy

https://youtu.be/RCdd8QM9YjY

Every patient scheduled for an elective surgical procedure in Baltimore area hospitals is required to have a COVID-19 pcr study done preoperatively,  and if negative, quarantine themselves until admitted. Since reopening my EMG practice,I have adopted this procedure  and also required a pcr study, mainly because of my age, my wife's age ,and her comorbidities. I have not insisted on the quarantine. Virtually all patients have understood and complied with this request. We are now able to obtain the nasal swab in our office with results returned from Quest within 3 days. This allows the patient to choose where they would like to have the swab done. A very few rare patients have refused to be tested, but for no consistent reason, other than for fear.
i wonder how others feel about pre procedure pcr testing. It is certainly not as good without quarantines,but if someone becomes ill, at least we will have some record of the patient's status and it should be of help in contact tracing.

What is the difference in area and duration on a CMAP and what does it mean? Is one more important than the other?

This is a waveform that a member recorded last week from the APB in a 66 year old woman.  We are sharing it as an 'unknown' waveform to see what others think.  More information and the 'answer' will be shared later.

Does such a diagnosis objectively exist?

 Is there evidence based literature that supports this offered diagnosis in a 55 yo with normal clinical and edX exams of an upper limb with diffuse pain?

I can recall being told by Neil Spielholtz, PhD, when I was  a resident/fellow in neuromuscular medicine in 1970, that facilitation of peripheral motor nerve conduction can be seen, especially when performing proneal/fibular motor studies. Stimulating the peroneal nerve at the ankle,will  occasionall cause  no response from the Edb .However, stimulating at the fibular head produces a response, and after this is done, stimulating at the ankle now produces a response. I recall being told that this was "facilitation." No further explanation was given, as much as I can recall. I recently have looked this up in the literature, since I have been doing this for 40 years, and have never given it much thought. If any of the  basic scientists out there can explain this to me, I would be very appreciative 

I am seeking the opinion of fellow neurologists/neurophysiologists as to whether you consider clinical examination, history taking and explanation of results and discussion of management as part of the neurophysiology study or is it considered as a separate consultation?  In my clinic I (as a Neurologist) personally exam the patient and take their history and based on this, set a test protocol which a neuroscientist then performs.  I then see the patient in my office after the study is completed for discussion of the results and management recommendations, and I provide a detailed report back to the referring physician.  

I would appreciate a simple yes or no response to the question:  does the above process allow billing of an EDX study and a consultation?

Thanking you in advance. 

John 

In various Maryland medical institutions, the degree of testing for Covid 19 before surgeries and diagnostic procedures varies greatly from one institution to another. With most surgical procedures patients are required to have a PCR test done during the week prior to their surgery, and they are asked to isolate themselves after their test until their surgery is done. Patients having MRI or other imaging procedures are not usually required to have any testing done, and are simply asked basic questions about Covid exposure, and their temperature is measured on arrival at the facility. Inside the facility, no procedures seem to be taken other than everyone wearing facemasks. In our office we perform only electromyography and nerve conduction studies. All patients are required to have a PCR 19 study done prior to being seen, but we do not require the patient to isolate themselves after this is done. We have turned away patients who arrived without having been tested. During the procedure I wear gown, mask, shield, head cover and gloves on each patient and even though the COVID-19 test is negative, I assume that the patient could have been  infected after the test was done.I suppose I am halfway between the surgical procedure and the imaging studies with regard to precautions. I wonder how others are handling safety precautions now that we are much further into the pandemic then earlier this year. Patients wonder why I am being so strict, but since we spend so much time in close quarters with the patients, I believe our degree of caution is appropriate. 

hi
could RNS be used for following up patients with MG !? 
assessing recovery or response to treatment ?
by comparing  pre  & post medication results 

What policies does your lab follow in regard to archiving raw data from EMGs/waveforms?  Do you archive for a certain length of time?  Any recommendations are welcome.

I have what may be a stupid question for many of you, but I do not see much motor neuron disease in my practice, so I wanted to ask the general question.  I know that denervation and re-innervation are seen together in the same muscles in motor neuron disease, but are polyphasics a necessary component to the re-innervation, or would chronic neuropathic motor units also be considered enough?  How often do you see polyphasia in motor neuron disease?  Thanks so much for your help in advance! 

Dear colleagues,
Report cases to the International Neuromuscular COVID-19 Database and become a member of the International Neuromuscular COVID-19 Consortium!
Over the last couple of months an international group of neuromuscular health care professionals have been working on creating an International Neuromuscular COVID-19 database to monitor and report the outcomes of COVID-19 occurring in patients with Neuromuscular Diseases. The database already includes almost 100 cases from various countries worldwide, including the UK, Spain, South Africa, The Netherlands and India.
There is an urgent need to understand outcomes of patients who acquire SARS-CoV‐2 infection and are receiving immunosuppressants and/or have disease features (e.g. cardiac or respiratory involvement) that may affect the outcome of COVID-19. This will help guide neuromuscular specialists in advising and caring for their patients.
 
The database it hosted by University College London (UCL) in the UK, at uses a secure RedCap platform; the database website can be found below:
https://www.ucl.ac.uk/centre-for-neuromuscular-diseases/news/2020/may/neuromuscular-covid-19-database  
We encourage colleagues to report ALL cases of COVID-19 in their neuromuscular patients, regardless of severity (including asymptomatic patients). Understanding less severe cases or even mild cases will help us understand further those who develop the most severe form. The contribution of contributions of colleagues reporting cases to the database will be duly acknowledged in publications arising from this international effort.
Target users are neuromuscular consultants / fellows / nurses / allied health professionals that become aware of NMD patients with COVID-19. We ask colleagues to report after a minimum of 7 days and sufficient time has passed to observe the disease course through resolution of acute illness and/or death. It is also possible for the reporter to return to the same case and update/complete the questionnaire.
We hope you will actively contribute to this voluntary reporting system. Through broad scale participation and collaboration, we will be able to answer these very pressing questions for our neuromuscular patients and their caregivers.
 The UK Health Research Authority (HRA) was consulted and advised that this project is considered to be a research database and that it does NOT require review by an NHS Research Ethics Committee (REC). It is a database involving previously collected and available, non-identifiable information. There is NO requirement for patient consent. Although this does not cover all nations in Europe and worldwide we believe this will be the position likely taken by many authorities across Europe/the world. Please check with your local authority if you are unsure. Please contact us if you require any additional details in order to obtain regulatory approval to submit cases in your country. 
The University of Kansas Medical Center IRB / REC also considers this to be retrospective data collection, therefore not requiring patient consent. But as indicated above please check with your local IRB.
With thanks and best wishes,
Mazen Dimachkie and Pedro Machado
mdimachkie@kumc.edu
p.machado@ucl.ac.uk