[A case of anti-MuSK antibody-positive myasthenia gravis with dropped head as the initial presenting symptom].

A 53-year-old woman was admitted to our hospital because of dropped head. Neurological examination showed no abnormality except for weakness of the neck extensor muscles. Her symptoms worsened in the evening, requiring her to support her head by placing her hand against her chin. Edrophonium and repetitive stimulation tests gave negative results, and anti-acetylcholine receptor antibodies were not detected. She had no thymoma. However, she was found to have a high serum titer of anti-MuSK antibody (37.3 nM). She was diagnosed as having myasthenia gravis (MG) and treatment with pyridostigmine was started. However, this had to be withdrawn because of fasciculation as an adverse effect. She was therefore treated with prednisolone, and this resulted in marked improvement. The initial presenting symptom in this case was dropped head, and there were none of the results of laboratory or electrophysiological examinations that are usually typical of MG. MG was eventually diagnosed by measurement of anti-MuSK antibody. The present case suggests that a patient presenting with dropped head without any obvious cause needs to be studied for the presence of anti-MuSK antibody.

Cervical dystonia induced by cervical spine surgery: a case report.

STUDY DESIGN: A case report. OBJECTIVES: To describe an interesting patient who underwent a three-level corpectomy of the cervical spine complicated by cervical dystonia and eventually treated successfully with botulinum toxin injections. SUMMARY OF BACKGROUND DATA: Cervical dystonia is a relatively rare disease and unfamiliar to many clinicians. Various types of peripheral trauma or peripheral lesion have been reported to induce cervical dystonia. However, to the best of our knowledge, there have been no reports about cervical dystonia following cervical spine surgery. METHODS: We present a case of a 45-year-old man who developed severe axial neck pain after cervical anterior corpectomy and fibula strut grafting due to cervical myelopathy. His neck pain gradually worsened, and involuntary spasmodic neck movement developed 6 weeks after operation when his halo-vest was removed. Initially, we considered his complaint to be transient or psychogenic, and diagnosis of cervical dystonia was delayed until 14 weeks after operation. RESULTS: Pharmacologic treatment was unsuccessful, but he was successfully treated with local intramuscular injections of botulinum toxin. CONCLUSIONS: It must be kept in mind that cervical spine surgery is not an exceptional precipitator of cervical dystonia, despite the fact that it is extremely rare.

Hypertensive brainstem encephalopathy.

A 45-year-old man developed severe arterial hypertension associated with unusual hyperintensity in the brainstem, around the right internal capsule and in the deep white matter around the bilateral anterior horn of the lateral ventricle on T2-weighted and fluid-attenuated inversion-recovery images. The characteristic clinical findings were mild left hepiparesis and altered mental status which corresponded to the lesions of MR imagings. The lesions improved gradually with improvements in hypertension, which suggested that edema could be the principal cause of the unusual hyperintensity on MR images.