Objective to analyze the long term effect of botulinum toxin a (Btx-A) in cervical dystonia and to discuss the incidence and mechanisms of secondary non-responsiveness.
目的研究肉毒毒素a治疗颈部肌张力障碍的长期疗效，探讨继发性无应答现象的发生率及相关机制。
2
The secondarydystonia is caused by brain trauma, infection, or special stimulation of external environment, etc.