Fiberoptic endoscopic evaluation of swallowing with simultaneous tensilon application in diagnosis and therapy of myasthenia gravis

Background Dysphagia is a common symptom in myasthenia gravis (MG). Clinical examination alone fails to detect and grade myasthenic dysphagia sufficiently. For a more precise examination of swallowing function in myasthenia gravis additional technical tools are necessary. Objective To investigate the diagnostic and therapeutic impact of fiberoptic endoscopic evaluation of swallowing with simultaneous Tensilon application (FEES-Tensilon Test) in myasthenia gravis. Methods FEES-Tensilon Test was performed following a standardized protocol. Four severely affected patients with dysphagia as their leading symptom were examined. Dysphagia was characterized by five salient endoscopic findings: leakage, delayed swallowing reflex, penetration, aspiration and residues. If a normalisation or at least an improvement of swallowing function occurred shortly after Tensilon administration the FEES-Tensilon Test was rated as being positive. Results In three patients the FEES-Tensilon Test successfully detected MG-related dysphagia. In one patient with dysphagia caused by oculopharyngeal muscular dystrophy the FEES-Tensilon Test was truly negative. Beside an early diagnosis of MG-related dysphagia, the FEES-Tensilon Test was useful in the differentiation between myasthenic and cholinergic crisis and in guiding treatment decisions. In all patients the FEES-Tensilon Test was superior to clinical evaluation of dysphagia. No severe side effect occurred while performing the FEES-Tensilon Test. Conclusion The FEES-Tensilon Test is a suitable tool in the diagnosis and therapy of myasthenia gravis with pharyngeal muscles weakness.