[The study of phonatory function in myasthenia gravis patients].

OBJECTIVE: To investigate the phonatory function in myasthenia gravis patients and the role of acoustic analysis technique in the diagnosis and the assessment of therapeutic effect on treatment of myasthenia gravis. METHOD: Eighty-three myasthenia gravis patients diagnosed definitely in neurology were divided into two groups, ocular group and generalized group. Each group included male group and female group. Acoustic measures were carried out before and after neostigmine test and treatment. Forty healthy subjects including twenty male and twenty female served as control groups. The basic parameters of the voice using computed voice analysis included F0, shimmer, jitter and NNE. Independent-Samples T Test and Paired-Samples T Test were used. RESULT: The value of F0 and NNE increased in generalized group. The changes of F0 and NNE in generalized group were found to be statistically significant (P < 0.01, 0.05). Neostigmine resulted in an improvement in the parameters of F0 and NNE, the same condition happened after the treatment (P < 0.01). CONCLUSION: Phonatory function of generalized myasthenia gravis patients is abnormal. F0 and NNE increase in generalized myasthenia gravis patients and decrease after the treatment or the intake of neostigmine. Acoustic analysis is a useful method in the diagnosis and assessment of generalized myasthenia gravis patients.