Olga Waln

An update on tardive dyskinesia: from phenomenology to treatment.

Tardive dyskinesia (TD), characterized by oro-buccal-lingual stereotypy, can manifest in the form of akathisia, dystonia, tics, tremor, chorea, or as a combination of different types of abnormal movements. In addition to movement disorders (including involuntary vocalizations), patients with TD may have a variety of sensory symptoms, such as urge to move (as in akathisia), paresthesias, and pain. TD is a form of tardive syndrome—a group of iatrogenic hyperkinetic and hypokinetic movement disorders caused by dopamine receptor-blocking agents. The pathophysiology of TD remains poorly understood, and treatment of this condition is often challenging. In this update, we provide the most current information on the history, nomenclature, etiology, pathophysiology, epidemiology, phenomenology, differential diagnosis, and treatment of TD.

Paroxysmal Movement Disorders

Paroxysmal dyskinesias represent a group of episodic abnormal involuntary movements manifested by recurrent attacks of dystonia, chorea, athetosis, or a combination of these disorders. Paroxysmal kinesigenic dyskinesia, paroxysmal nonkinesigenic dyskinesia, paroxysmal exertion-induced dyskinesia, and paroxysmal hypnogenic dyskinesia are distinguished clinically by precipitating factors, duration and frequency of attacks, and response to medication. Primary paroxysmal dyskinesias are usually autosomal dominant genetic conditions. Secondary paroxysmal dyskinesias can be the symptoms of different neurologic and medical disorders. This review summarizes the updates on etiology, pathophysiology, genetics, clinical presentation, differential diagnosis, and treatment of paroxysmal dyskinesias and other episodic movement disorders.

Continuous in-home monitoring of essential tremor.

BACKGROUND Essential tremor (ET) is typically measured in the clinic with subjective tremor rating scales which require the presence of a clinician for scoring and are not appropriate for measuring severity throughout the day. Motion sensors can accurately rate tremor severity during a set of predefined tasks in a laboratory. METHODS We evaluated the ability of motion sensors to quantify tremor during unconstrained activities at home. 20 ET subjects wore a wireless sensor continuously for up to 10 h daily on two days and completed hourly standardized tremor assessments involving pre-defined tasks. Mathematical models were used to predict tremor rating scores from the sensor data. RESULTS At home tremor scores from hourly standardized assessments correlated with at home tremor scores estimated during unconstrained activities immediately following the standardized assessments. The hourly standardized assessments did not significantly fluctuate throughout the day, while fluctuations in the continuous assessments tended to follow changes in voluntary activity level. Both types of tremor ratings (standardized and continuous) showed high day-to-day test-retest reliability with intraclass correlation coefficients ranging from 0.67 to 0.90 for continuous ratings and 0.77 to 0.95 for standardized ratings. CONCLUSIONS Results demonstrate the feasibility of continuous monitoring of tremor severity at home, which should provide clinicians with a measure of the temporal pattern of tremor in the context of daily life and serve as a useful tool for the evaluation of novel anti-tremor medications in clinical trials.

Rechargeable Deep Brain Stimulation Implantable Pulse Generators in Movement Disorders: Patient Satisfaction and Conversion Parameters

Rechargeable (RC) implantable pulse generators (IPGs) for deep brain stimulation (DBS) in movement disorders have recently become available. No guidelines exist for parameter adjustment after conversion of non‐RC to RC IPGs, or reports of patient satisfaction with RC IPGs when used as initial DBS device or after conversion from non‐RC IPGs.

Zolpidem improves tardive dyskinesia and akathisia.

A 67-year-old woman with a long history of multiple personality disorder was treated with haloperidol and thioridazine in her 50s for psychosis with suicidal ideations and developed blepharospasm, repetitive jaw opening and tongue thrusting, difficulty swallowing, noisy breathing with inspiratory gasps, anterocollis, and choreiform movements in the legs (Video 1). She was diagnosed with TD, tardive cranialcervical dystonia, and dystonic respiratory dysregulation. Discontinuation of antipsychotics, and trials of trihexyphenidyl and levodopa were unsuccessful. Tetrabenazine 37.5 mg daily provided modest improvement. The patient once noted improvement of all abnormal movements 30 minutes after taking zolpidem for a daytime nap but with no somnolence (Video 2). She has been taking zolpidem 10 mg 2 to 3 times daily for 11 months with the same benefit.

Bilateral globus pallidus internus deep brain stimulation after bilateral pallidotomy in a patient with generalized early‐onset primary dystonia

We read with great interest the recent publication by Fonoff et al. describing 4 patients with generalized dystonia who underwent bilateral subthalamic nucleus (STN) deep brain stimulation (DBS) after bilateral pallidotomy. They imply that because of prior ablation to the pallidum, STN DBS may be a preferred approach in these patients. We describe here a patient with generalized early-onset primary dystonia (DYT1) treated successfully with bilateral pallidotomy and subsequent bilateral globus pallidus internus (GPi) DBS. To our knowledge, this is the first case of generalized dystonia treated with bilateral GPi DBS after bilateral pallidotomy. This 30-year-old woman developed cervical and right hand dystonia with dystonic tremor at the age of 7 years. Over the next few years, dystonia spread to the proximal arms, legs, and especially trunk. By age 14 years, the patient had severe generalized dystonia with marked impairment of the use of both arms, severe cervical and jaw-opening dystonia resulting in anarthria, and so severe dystonic camptocormia that her head nearly touched the ground with the attempt to ambulate (Video 1). The patient’s family history was positive for milder forms of dystonia in mother (writer’s cramp) and 2 maternal distant relatives. DNA testing confirmed DYT1 gene mutation. Trials of levodopa, trihexyphenidyl, clonazepam, and tizanidine were unsuccessful. The patient initially benefited but subsequently lost the effect of botulinum toxin A (BoNT) because of the presence of blocking antibodies detected by the mouse bioassay. At the age of 14 years, she became the first patient in our Center who underwent bilateral pallidotomy surgery and was previously reported as patient 7 in the case series of 8 patients with generalized dystonia treated with pallidotomy. The patient had dramatic improvement of oromandibular, cervical, truncal, and appendicular dystonia (Video 1); however, 6 months after the surgery she had a gradual recurrence of cervical dystonia

Neuro-ophthalmology of movement disorders

ABSTRACT Introduction: Ophthalmologic abnormalities, including visual impairment and ocular motor dysfunction, are common in patients with movement disorders. The impact of the ocular symptoms on the patients’ quality of life is often underestimated. Pathophysiology of these symptoms remains poorly understood. In this review, a concise but comprehensive summary of ophthalmologic features of the most common movement disorders and a discussion of their pathophysiology and treatment are provided. Areas covered: A systematic review was conducted of the literature on ophthalmologic signs in Parkinson’s disease (PD), atypical parkinsonism, cerebellar disorders, Huntington disease (HD), dystonia, tics, and functional (psychogenic) movement disorders. Expert commentary: Recognition of certain neuro-ophthalmologic symptoms and signs and their association with movement disorders can assist in the diagnosis and management of patients with movement disorders. Neuroanatomy of visual and ocular motor pathways, pathological changes in the cerebral networks involved in vision and the control of eye movements can provide further insight into pathophysiology of movement disorders.

Use of Rechargeable DBS Implantable Pulse Generators in Patients with Movement Disorders: Patient Satisfaction and Stimulation Parameters (P02.237)

Activa RC (Medtronic Inc; Minneapolis, MN) first rechargeable (RC) dualchannel IPG for DBS approved by FDA in May 2009 Offers practitioners wider range of programming possibilities than older IPGs (e.g. interleaving) Offers patients more control over DBS therapy (multiple groups, parameter adjustment within pre-set range) Advertised battery life is 9 years Particularly useful in patients who require high-energy stimulation and faster depletion of non-RC IPGs (e.g., GPI DBS in dystonia, TS) Thinner profile than other IPGs (e.g., Soletra, Kinetra, Activa PC)