Faculty Bibliography

Musicians' dystonia is a task-specific and painless loss of motor control in a previously well-executed task. It is increasingly recognized in the medical and musical community. Recent advances in neuroimaging, transcranial magnetic stimulation and novel techniques in electroencephalography have shed light on its underlying pathophysiology. To date, a deranged cortical plasticity leading to abnormal sensorimotor integration, combined with reduced inhibition across several levels of the motor pathway are likely mechanisms.This paper reviews the various phenomenology of musician's dystonia across keyboard, string, brass, flute and drum players. Treatment is often challenging. Medical therapies like botulinum toxin injection and rehabilitation method with sensorimotor training offer symptomatic relief and return to baseline performance to some musicians.

The definition of dystonia has been a subject of much debate and controversy for the last century. In this paper, a practical definition of dystonia for the movement disorders expert is presented, based on a new algorithm. (c) 2013 Movement Disorder Society.

BACKGROUND: Symptoms of spasmodic dysphonia (SD) are usually managed successfully with botulinum toxin injections. Vocal tremor (VT), which accompanies SD, has a poor response to this treatment. CASE REPORT: We report a case of a female with SD and VT who became symptom-free for 10 months after the intake of a single dose of sodium oxybate (Xyrem(R)). The long-term treatment effect correlated with attenuated brain activity in the key regions of dystonic brain network. DISCUSSION: Our case demonstrates that the novel treatment of sodium oxybate may hold promise for SD patients, especially those who have associated VT.

BACKGROUND: Adult-onset focal lower extremity (LE) dystonia is rare, but there have recently been a number of case series that have reported an idiopathic variant triggered during ambulation. METHODS: We describe nine patients with idiopathic, focal task-specific LE dystonia. We conducted a comparative analysis that included our cohort and several recently published case series to further characterize the disorder. RESULTS: A total of 48 patients (37 female, 11 male) were compared. The average age of onset was 48 years; 36 patients had distal extremity involvement (75%), 5 proximal (10%), and 7 both proximal and distal (15%). Among 33 patients in which the dystonic side was known, 20 were affected on the left (61%). Inversion of the foot with flexion of one or more toes was the most prevalent pattern in those with distal extremity involvement. DISCUSSION: This is a novel task-specific dystonia triggered during ambulation that is often misdiagnosed as an orthopedic or psychogenic issue.

The syndrome of progressive supranuclear palsy-like syndrome is a rare complication of ascending aortic aneurysm repair. We report two patients with videos and present a table of prior reported cases. To our knowledge there is no previously published video of this syndrome. The suspected mechanism is brainstem injury though neuroimaging is often negative for an associated infarct. We hope our report will increase recognition of this syndrome after aortic surgery, especially in patients with visual complaints.

OBJECTIVE: To identify brain regions with metabolic changes in DYT11 myoclonus-dystonia (DYT11-MD) relative to control subjects and to compare metabolic abnormalities in DYT11-MD with those found in other forms of hereditary dystonia and in posthypoxic myoclonus. METHODS: [(18)F]-fluorodeoxyglucose PET was performed in 6 subjects with DYT11-MD (age 30.5 +/- 10.1 years) and in 6 nonmanifesting DYT11 mutation carriers (NM-DYT11; age 59.1 +/- 8.9 years) representing the parental generation of the affected individuals. These data were compared to scan data from age-matched healthy control subjects using voxel-based whole brain searches and group differences were considered significant at p < 0.05 (corrected, statistical parametric mapping). As a secondary analysis, overlapping abnormalities were identified by comparisons to hereditary dystonias (DYT1, DYT6, dopa-responsive dystonia) and to posthypoxic myoclonus. RESULTS: We found significant DYT11 genotype-specific metabolic increases in the inferior pons and in the posterior thalamus as well as reductions in the ventromedial prefrontal cortex. Significant phenotype-related increases were present in the parasagittal cerebellum. This latter abnormality was shared with posthypoxic myoclonus, but not with other forms of dystonia. By contrast, all dystonia cohorts exhibited significant metabolic increases in the superior parietal lobule. CONCLUSIONS: The findings are consistent with a subcortical myoclonus generator in DYT11-MD, likely involving the cerebellum. By contrast, subtle increases in the superior parietal cortex relate to the additional presence of dystonic symptoms. Although reduced penetrance in DYT11-MD has been attributed to the maternal imprinting epsilon-sarcoglycan mutations, NM-DYT11 carriers showed significant metabolic abnormalities that are not explained by this genetic model.