Can NCS be gold standard test for CTD?
Presentation. Speaker Viktoras Kubaitis
15th EFORT Congress in Istanbul, 5-8 of June 2013
More political than statistical one. The main idea is that you cannot trust not standardised NCS and there is most important thing in our diagnosis making Symptoms and complains of the patient. Unfortunately all laboratory test even standardised NCS are just secondary additional help to make proper decision on treatment.
15th EFORT Congress in Istanbul, 5-8 of June 2013
More political than statistical one. The main idea is that you cannot trust not standardised NCS and there is most important thing in our diagnosis making Symptoms and complains of the patient. Unfortunately all laboratory test even standardised NCS are just secondary additional help to make proper decision on treatment.
SLIDE No 1
There are different countries with different Law system, different NHS with different CTS treatment guidelines but decision making usually is based on dividing the condition in mild moderate and severe, which is sometimes difficult differentiate in real clinical circumstances. My talk is about CTS diagnosis making, NCS and CTD and CTS treatment algorithm and decision making in general.
SLIDE No 2
This is the patient with possible CTS who coming to our hand clinic. Some of them are bringing to us very expensive material. All our patients are tested by NCS in our hospital. 40% of them are usually getting positive NCS answer and are
treated by CTD. Some of them are getting enough symptoms to diagnose CTS but NCS could be negative. For that reason sometimes we are sending them to another hospital for NCS which are performed by other Neurophysiologist by standardised procedure. But any way 60% of patient are treated conservatively and they are usually not happy about the treatment result. There is not always a match between different neurophysiologist NCS answer. For that reason we started interest way it happens like that.
SLIDE No 3
We are getting fife groups of patients. You can see symptoms in the second column. NCS result in a third second column. The Comparison of symptoms with NCS you can see in a third column and expected presumed result in a last column. The first one is patients with classical symptoms and NCS are confirming the diagnosis. The patient are going through the surgery and usually getting good results. Second group of patients are with enough symptoms to make a CTS diagnosis but they are getting negative answer from our hospital made NCS. We are sending these patients sometimes to another hospital for
NCS check and some of them getting confirmed neurophysiological tests. These patients are getting CTD and usually getting good result. There is third group of patient who have symptoms for proper CTS diagnosis but there is still NCS negative.
We call this result False Negative and it is impossible to operate these patients from point of view of Law. Treatment result is rather unpredictable. The forth group of patients are these who getting other symptoms related with Ulnar or Radial nerve entrapment. These patients as usual bringing back colourful NCS answer but CTS cannot be confirmed. Operation is
impossible. Fifth group of patients with symptoms which coming from the neck as Double crash syndrome. No confirmation from the NCS. And we are lucky because we are able to do F waves and EMG.
SLIDE No 4
There are a lot of hand surgeons who are not happy about results of NCS and these surgeons thing that NCS are useless and just wasting of time of the patient. Why does it happen? We are testing sensory response over the wrist. We checking motor conduction of nerves and sometimes we think that it is enough. No! It is not enough. To get all view what happens in the arm of the patient we need F waves and EMG. F waves test is like an echo. We are stimulating verve with strong electrical stimuli and stimuli goes to spine and comes back so we can check all nerve length from the spine to the distal entrapment site.
SLIDE No. 5
It is just enough a Scored questioner for simple classical cases even if it is severe entrapment.
SLIDE No 6
There is another reason why there are no match symptoms with NCS. NCS testing only nerves which are myelinated. Pain related problems are something to do with tiny nerves which cannot be evaluated by usual NCS.
SLIDE No 7
Standardised NCS mean that document which you are getting from neurophysiology department have to be not report – it must to be conclusion with prognosis. It should be Standard distance between electrodes. You should have possibility for F wave and EMG. Every time you should test both arms. The Temperature of skin, Weight and height of patient, Flexion
of the elbow in 90 degrees and position of the patient should mentioned on the report. Laboratory should present its own normal ranges, sensitivity and specificity of the test for definite group of patient, which subtype of NCS from 27 subtypes was
done.
SLIDE No 8
You can see results of our study. We tested 60 patients. Not standardised NCS made 36% false positive and false negative
result per all group. There are patients treated conservatively in a second column. Patients were treated by CTD are in a third
column. Patient with additional ulnar or Radial nerve entrapment situated in a forth and Patients with a clinic coming from the neck entrapment in a last column. As you see confirmation rate decreases and false positive - false negative result increases.
SLIDE No 9
There is different expression of our study results and you can see how many there are false positive and false negatives results in columns with additional ulnar or radial nerve entrapment or spine related pathology.
SLIDE No 10
My take away message for you is reassurance that NCS is enough sensitive laboratory test. It could be like shield for legal protection of hand surgeon but NCS have to be standardised and we should know why sometimes NCS cannot match
clinical symptoms of patient. I want to remind you that most important thing in our everyday practice are complaints tests and symptoms of patients but laboratory tests are just secondary thing in diagnosis making.
There are different countries with different Law system, different NHS with different CTS treatment guidelines but decision making usually is based on dividing the condition in mild moderate and severe, which is sometimes difficult differentiate in real clinical circumstances. My talk is about CTS diagnosis making, NCS and CTD and CTS treatment algorithm and decision making in general.
SLIDE No 2
This is the patient with possible CTS who coming to our hand clinic. Some of them are bringing to us very expensive material. All our patients are tested by NCS in our hospital. 40% of them are usually getting positive NCS answer and are
treated by CTD. Some of them are getting enough symptoms to diagnose CTS but NCS could be negative. For that reason sometimes we are sending them to another hospital for NCS which are performed by other Neurophysiologist by standardised procedure. But any way 60% of patient are treated conservatively and they are usually not happy about the treatment result. There is not always a match between different neurophysiologist NCS answer. For that reason we started interest way it happens like that.
SLIDE No 3
We are getting fife groups of patients. You can see symptoms in the second column. NCS result in a third second column. The Comparison of symptoms with NCS you can see in a third column and expected presumed result in a last column. The first one is patients with classical symptoms and NCS are confirming the diagnosis. The patient are going through the surgery and usually getting good results. Second group of patients are with enough symptoms to make a CTS diagnosis but they are getting negative answer from our hospital made NCS. We are sending these patients sometimes to another hospital for
NCS check and some of them getting confirmed neurophysiological tests. These patients are getting CTD and usually getting good result. There is third group of patient who have symptoms for proper CTS diagnosis but there is still NCS negative.
We call this result False Negative and it is impossible to operate these patients from point of view of Law. Treatment result is rather unpredictable. The forth group of patients are these who getting other symptoms related with Ulnar or Radial nerve entrapment. These patients as usual bringing back colourful NCS answer but CTS cannot be confirmed. Operation is
impossible. Fifth group of patients with symptoms which coming from the neck as Double crash syndrome. No confirmation from the NCS. And we are lucky because we are able to do F waves and EMG.
SLIDE No 4
There are a lot of hand surgeons who are not happy about results of NCS and these surgeons thing that NCS are useless and just wasting of time of the patient. Why does it happen? We are testing sensory response over the wrist. We checking motor conduction of nerves and sometimes we think that it is enough. No! It is not enough. To get all view what happens in the arm of the patient we need F waves and EMG. F waves test is like an echo. We are stimulating verve with strong electrical stimuli and stimuli goes to spine and comes back so we can check all nerve length from the spine to the distal entrapment site.
SLIDE No. 5
It is just enough a Scored questioner for simple classical cases even if it is severe entrapment.
SLIDE No 6
There is another reason why there are no match symptoms with NCS. NCS testing only nerves which are myelinated. Pain related problems are something to do with tiny nerves which cannot be evaluated by usual NCS.
SLIDE No 7
Standardised NCS mean that document which you are getting from neurophysiology department have to be not report – it must to be conclusion with prognosis. It should be Standard distance between electrodes. You should have possibility for F wave and EMG. Every time you should test both arms. The Temperature of skin, Weight and height of patient, Flexion
of the elbow in 90 degrees and position of the patient should mentioned on the report. Laboratory should present its own normal ranges, sensitivity and specificity of the test for definite group of patient, which subtype of NCS from 27 subtypes was
done.
SLIDE No 8
You can see results of our study. We tested 60 patients. Not standardised NCS made 36% false positive and false negative
result per all group. There are patients treated conservatively in a second column. Patients were treated by CTD are in a third
column. Patient with additional ulnar or Radial nerve entrapment situated in a forth and Patients with a clinic coming from the neck entrapment in a last column. As you see confirmation rate decreases and false positive - false negative result increases.
SLIDE No 9
There is different expression of our study results and you can see how many there are false positive and false negatives results in columns with additional ulnar or radial nerve entrapment or spine related pathology.
SLIDE No 10
My take away message for you is reassurance that NCS is enough sensitive laboratory test. It could be like shield for legal protection of hand surgeon but NCS have to be standardised and we should know why sometimes NCS cannot match
clinical symptoms of patient. I want to remind you that most important thing in our everyday practice are complaints tests and symptoms of patients but laboratory tests are just secondary thing in diagnosis making.
