Diagnostic value of low-frequency repetitive nerve stimulation in patients with ocular myasthenia gravis

Abstract

Objective To investigate the diagnostic value of low-frequency repetitive nerve stimulation(RNS) in patients with ocular myasthenia gravis(MG). Methods The clinical data of the low-frequency RNS of 54 in-patients with ocular MG were analyzed. Results The positive rate of low-frequency RNS was 53.7% in 54 patients.The abnormal rate of the facial nerve and the proximal limb nerve was significantly higher than that of low limb distal nerve.The differences were statistically significant(χ2=6.783, P=0.009; χ2=4.167, P=0.041). In all the examined nerves, the abnormal rate of right facial nerve was the highest(46.3%), and the lowest on the ulnar nerve(11.1%). The abnormal rate was statistically significant in all these nerves(χ2=21.995, P=0.001). Conclusion Low-frequency RNS plays an important role in the diagnosis of ocular MG, and the facial nerve should be the first choice in this examination. Key words: Ocular myasthenia gravis; Low-frequency repetitive nerve stimulation