Ocular vestibular evoked myogenic potentials in patients with myasthenia gravis

Recruitment & Eligibility

Status: Completed

Sex: Not specified

Target Recruitment: 102

Inclusion Criteria

Cross-sectional study (objective 1)
Patients with MG:
* Patient is legally capable
* Definitive diagnosis of MG defined as the presence of a typical history and
at least one positive ancillary test,
including edrophonium testing, RNS, and serum autoantibodies
(anti-acetylcholine receptor [AChR], anti-muscle
specific tyrosine kinase [MuSK]).
Healthy controls:
* Healthy control is legally capable
* No diagnosis of MG
* Absence of disease that involves eye-muscle function or any other muscle
disease
Controls with other neuromuscular diseases:
* Patient is legally capable
* No diagnosis of MG
* Definite diagnosis of other neuromuscular disease
Controls non-neuromuscular diseases that can cause diplopia:
* Patient is legally capable
* No diagnosis of MG
* No other neuromuscular disease
* Definite diagnosis that can cause diplopia
* Presence of diplopia
Longitudinal study (objective 2)
Patients with the clinical suspicion of MG:
* Patient is legally capable
* MG is in the differential diagnosis
* No definitive diagnosis of MG'
Neostigmine study (objective 3)
Patients who undergo an acetylcholinesterase inhibitor (neostigmine) test within
routine clinical care:
* Patient is legally capable
* MG is in the differential diagnosis
* Patient undergoes neostigmine test for diagnostic purposes

Exclusion Criteria

A potential subject who meets any of the following criteria will be excluded
from participation in this study:, * Patients who are legally incapable
* Patients who are under the age of 16
* Patients with known vestibulo-cochlear disorders

Study & Design

Study Type: Observational non invasive

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
<p>1. The endpoint for objective 1 is the amount of decrement. We will investigate<br /><br>cross-sectionally which cut-off value results in the best combination of<br /><br>sensitivity and specificity by calculating a ROC curve. We will compare this<br /><br>cut-off value with that of Valko et al.. </p><br>

Secondary Outcome Measures

Name	Time	Method
<p>2. The endpoint for objective 2 is the presence of significant decrement, using<br /><br>the cut-off value established in objective 1 in order to calculate the<br /><br>specificity and sensitivity of the oVEMP test longitudinally.<br /><br>3. The endpoint for objective 3 is the decrease of decrement. We will study<br /><br>whether decrement decreases after administration of acetylcholinesterase<br /><br>inhibitors (neostigmine test).<br /><br>4. The endpoint in objective 4 is the reproducibility of decrement in two<br /><br>consecutive measurements in the same subjects.</p><br>