Is it possible to stimulate a eye muscle or underarmmuscle for a prolonged time in a painless way and is this information contributory to make the diagnosis and grade clinical in MG and LEMS?
ID
Source
Brief title
Condition
- Neuromuscular disorders
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
CMAP-amplitude and change of amplitude after prolonged stimulating and
recording. Is hte pattern different between controls itselves and between
controls and patients?
Secondary outcome
Is the technique painless indeed?
Background summary
RNS is used for the diagnosis of MG and LEMS. Unfortunately it seems
insufficiently able to mimick the "normal" situation of our body muscles to
enlighten the pathophysiologic mechanism of weakness in patients. Clinical
protocols used nowadays to diagnose myasthenia require high-frequency
stimulation (over 30Hz) which is very painful. A painless technique to
stimulate at high frequencies will improve diagnostic sensitivity and will
diminish paitent's burden.
Study objective
Is it possible to stimulate a eye muscle or underarmmuscle for a prolonged time
in a painless way and is this information contributory to make the diagnosis
and grade clinical in MG and LEMS?
Study design
A thin needle is inserted subcutaneously besides the lateral eye or proximally
in the m. extensor digitorum communis. Stimulating (3 Hz, about 3-6 mA) the tip
of the needle is moveduntill visible contractions of forehead or underarm are
seen. The needle is fixated. In our experience stimulation itself is not
limited by pain.
A reliable and optimal CMAP-amplitude is determined. The 'black' (negative
entrance) as well as the 'red' (positive entrance) electrode are repositioned
to achieve this.
After obtaining the CMAP-amplitude the frequency is increased to 10 Hz and
recorded for three minutes. All responses are recorded. The recording will be
repeated for 30Hz and 50 Hz, both three minutes.
Study burden and risks
30 minutes, once. At the site of insertion a bruise might remain for some days.
Albinusdreef 2
2333 ZA
Nederland
Albinusdreef 2
2333 ZA
Nederland
Listed location countries
Age
Inclusion criteria
over 18 years old
MG: clinical signs and symptoms of MG, positive for anti-AChR antibodies and characteristic RNS EMG abnormalities (decrement over 10%) or abnormal Single Fibre EMG.
LEMS: clinical signs and symptoms of LEMS, positive for anti-VGCC antibodies and characteristic RNS EMG abnormalities (decrement over 10% and increment over 60%) or abnormal Single Fibre EMG.
Exclusion criteria
anticoagulant drugs
muscle and nerve diseases or diseases predisposing to nerve or muscled isease, for example diabetes mellitus
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL19304.058.07 |