Dystonia, a large group of abnormal movements triggered by skeletal muscles that cannot be controlled at will by the patient. It is a syndrome of distorted, repetitive involuntary movements and postural abnormalities of part or all of the body due to uncoordinated, intermittent, and sustained contractions of the synergistic and antagonistic muscles of the skeletal muscles. The treatment of dystonia is a major challenge in the field of neurology, second only to tremor palsy in the frequency of extrapyramidal disorders. Botulinum toxin type A is the first-line drug for the treatment of dystonia, especially for focal dystonia, because of its potency, efficacy, less serious toxic side effects, and ease of operation. The main limited dystonia diseases: 1, the lateral side muscle spasm and simple eye muscle spasm: the lateral area spasm is limited to one side of the face of the involuntary clonic twitch. If it is limited to the eye muscle, it becomes oculomotor spasm. 2.Meige syndrome: It is mostly seen in middle-aged and elderly people, and is more common in women. Its clinical manifestations are mostly characterized by tonic, persistent and spastic contraction of orbicularis oculi muscle as the first symptom, and progressive aggravation, gradually involving orbicularis oculi muscle, perinasal muscle, orbicularis orbicularis orbicularis orbicularis muscle to mandibular muscle group, and in severe cases, functional blindness occurs in 1 to 2 years, and eventually loss of self-care ability, characterized by bilateral twitching. 3. Spastic squint: It is a disease caused by paroxysmal involuntary contraction of the cervical muscles, resulting in paroxysmal or continuous abnormal posture, which can be manifested as twisting or tilting of the neck. Other disorders: 4. Children with tic disorders may also be treated with this treatment if the clinical symptoms are limited to the face and or neck. Applications in other disciplines, such as pancreatic dystonia, hemorrhoids, etc., but not in the neurological context.