Deciphering the effects of STN DBS on neuropsychiatric fluctuations in Parkinson's disease.

The impact of subthalamic nucleus (STN) deep brain stimulation (DBS) on neuropsychiatric fluctuations in Parkinson´s disease (PD) remains unclear. The Neuropsychiatric Fluctuations Scale (NFS) can help to fill this gap, directly measuring fluctuations between the OFF- and ON-medication conditions. The NFS provides NFS-plus (hyperdopaminergic) and NFS-minus (hypodopaminergic) sub-scores.

Spatiotemporal Gait Differences before and after Botulinum Toxin in People with Focal Dystonia: A Pilot Study.

Background: The impact of focal dystonia on gait has attracted little attention and remains elusive. Considering the importance of both visual and head control in gait, blepharospasm and cervical dystonia should affect gait. Improvement of cervical/eyelid control following botulinum toxin (BTX) injections would translate into gait changes.

Fluctuations in Parkinson's disease and personalized medicine: bridging the gap with the neuropsychiatric fluctuation scale.

Background: Neuropsychiatric fluctuations (NpsyF) are frequent and disabling in people with Parkinson's disease (PD). In OFF-medication, NpsyF entail neuropsychiatric symptoms (NPS) like anxiety, apathy, sadness, and fatigue. In ON-medication, NpsyF consist in NPS, such as high mood, hypomania, and hyperactivity.

Long-term independence and quality of life after subthalamic stimulation in Parkinson disease.

Background And Purpose: Studies on long-term nonmotor outcomes of subthalamic nucleus stimulation in Parkinson disease (PD) are scarce. This study reports on very long-term non-motor and motor outcomes in one of the largest cohorts of people with advanced PD, treated for >10 years with subthalamic nucleus stimulation. The main outcome was to document the evolution of independence in activities of daily living.

Contribution of Basal Ganglia to the Sense of Upright: A Double-Blind Within-Person Randomized Trial of Subthalamic Stimulation in Parkinson's Disease with Pisa Syndrome.

Background: Verticality perception is frequently altered in Parkinson's disease (PD) with Pisa syndrome (PS). Is it the cause or the consequence of the PS?

Objective: We tested the hypothesis that both scenarios coexist.

Methods: We performed a double-blind within-person randomized trial (NCT02704910) in 18 individuals (median age 63.

Deep Brain Stimulation for Freezing of Gait in Parkinson's Disease With Early Motor Complications.

Background: Effects of DBS on freezing of gait and other axial signs in PD patients are unclear.

Objective: Secondary analysis to assess whether DBS affects these symptoms within a large randomized controlled trial comparing DBS of the STN combined with best medical treatment and best medical treatment alone in patients with early motor complications (EARLYSTIM-trial).

Methods: One hundred twenty-four patients were randomized in the stimulation group and 127 patients in the best medical treatment group.

Asymmetric STN DBS for FOG in Parkinson's disease: A pilot trial.

Background: In Parkinson's disease (PD), freezing of gait (FOG) is a highly disabling gait disorder. Though deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an efficient treatment for advanced PD, the management of STN DBS refractory FOG remains challenging.

Objective: To evaluate the long-term impact on FOG of unilateral stimulation reduction in PD treated with bilateral STN DBS.

Managing Gait, Balance, and Posture in Parkinson's Disease.

Purpose Of Review: Postural instability and gait difficulties inexorably worsen with Parkinson's disease (PD) progression and become treatment resistant, with a severe impact on autonomy and quality of life. We review the main characteristics of balance instability, gait disabilities, and static postural alterations in advanced PD, and the available treatment strategies.

Recent Findings: It remains very difficult to satisfactorily alleviate gait and postural disturbances in advanced PD.

The laser shoes: A new ambulatory device to alleviate freezing of gait in Parkinson disease.

Objective: To assess, in a cross-sectional study, the feasibility and immediate efficacy of laser shoes, a new ambulatory visual cueing device with practical applicability for use in daily life, on freezing of gait (FOG) and gait measures in Parkinson disease (PD).

Methods: We tested 21 patients with PD and FOG, both "off" and "on" medication. In a controlled gait laboratory, we measured the number of FOG episodes and the percent time frozen occurring during a standardized walking protocol that included FOG provoking circumstances.

Pedunculopontine nucleus deep brain stimulation in Parkinson's disease: A clinical review.

Pedunculopontine nucleus region deep brain stimulation (DBS) is a promising but experimental therapy for axial motor deficits in Parkinson's disease (PD), particularly gait freezing and falls. Here, we summarise the clinical application and outcomes reported during the past 10 years. The published dataset is limited, comprising fewer than 100 cases.

The Practicalities of Assessing Freezing of Gait.

Background: Freezing of gait (FOG) is a mysterious, complex and debilitating phenomenon in Parkinson's disease. Adequate assessment is a pre-requisite for managing FOG, as well as for assigning participants in FOG research. The episodic nature of FOG, as well as its multiple clinical expressions make its assessment challenging.

Physiology of freezing of gait.

Freezing of gait (FOG) is a common and debilitating, but largely mysterious, symptom of Parkinson disease. In this review, we will discuss the cerebral substrate of FOG focusing on brain physiology and animal models. Walking is a combination of automatic movement processes, afferent information processing, and intentional adjustments.

Polymorphism of the dopamine transporter type 1 gene modifies the treatment response in Parkinson's disease.

After more than 50 years of treating Parkinson's disease with l-DOPA, there are still no guidelines on setting the optimal dose for a given patient. The dopamine transporter type 1, now known as solute carrier family 6 (neurotransmitter transporter), member 3 (SLC6A3) is the most powerful determinant of dopamine neurotransmission and might therefore influence the treatment response. We recently demonstrated that methylphenidate (a dopamine transporter inhibitor) is effective in patients with Parkinson's disease with motor and gait disorders.

Neural substrates of levodopa-responsive gait disorders and freezing in advanced Parkinson's disease: a kinesthetic imagery approach.

Gait disturbances, including freezing of gait, are frequent and disabling symptoms of Parkinson's disease. They often respond poorly to dopaminergic treatments. Although recent studies have shed some light on their neural correlates, their modulation by dopaminergic treatment remains quite unknown.

Low-frequency versus high-frequency stimulation of the pedunculopontine nucleus area in Parkinson's disease: a randomised controlled trial.

Objective: To compare the influence of low-frequency (10-25 Hz) versus higher (60-80 Hz) frequency stimulation of the pedunculopontine nucleus area (PPNa) on akinaesia, freezing of gait and daytime sleepiness.

Method: We included nine patients with Parkinson's disease (PD) and severe gait disorders. In this double-blind randomised cross-over study, patients were assessed after 24 h of PPNa stimulation.

Stimulation of the pedunculopontine nucleus area in Parkinson's disease: effects on speech and intelligibility.

Improvement of gait disorders following pedunculopontine nucleus area stimulation in patients with Parkinson's disease has previously been reported and led us to propose this surgical treatment to patients who progressively developed severe gait disorders and freezing despite optimal dopaminergic drug treatment and subthalamic nucleus stimulation. The outcome of our prospective study on the first six patients was somewhat mitigated, as freezing of gait and falls related to freezing were improved by low frequency electrical stimulation of the pedunculopontine nucleus area in some, but not all, patients. Here, we report the speech data prospectively collected in these patients with Parkinson's disease.

The pathogenesis of Pisa syndrome in Parkinson's disease.

Postural abnormalities such as postural deviations affect nearly all patients with advanced Parkinson's disease and represent an important source of disability. Although their existence has long been known, their management remains a challenge as they respond poorly to medication, brain surgery, or physiotherapy. Improving management strategies will require better understanding of the mechanisms underlying such postural deformities.

Iowa gambling task impairment in Parkinson's disease can be normalised by reduction of dopaminergic medication after subthalamic stimulation.

Background: Impulse control disorders (ICD), including pathological gambling, are common in Parkinson's disease (PD) and tend to improve after subthalamic (STN) stimulation after a marked reduction of dopaminergic medication. In order to investigate the effect of STN stimulation on impulsive decision making, we used the Iowa Gambling task (IGT).

Methods: We investigated IGT performance in 20 patients with PD before STN surgery with and without dopaminergic treatment and in 24 age-matched controls.

Using motor imagery to study the neural substrates of dynamic balance.

This study examines the cerebral structures involved in dynamic balance using a motor imagery (MI) protocol. We recorded cerebral activity with functional magnetic resonance imaging while subjects imagined swaying on a balance board along the sagittal plane to point a laser at target pairs of different sizes (small, large). We used a matched visual imagery (VI) control task and recorded imagery durations during scanning.

Pedunculopontine nucleus area oscillations during stance, stepping and freezing in Parkinson's disease.

The pedunculopontine area (PPNa) including the pedunculopontine and cuneiform nuclei, belongs to the mesencephalic locomotor region. Little is known about the oscillatory mechanisms underlying the function of this region in postural and gait control. We examined the modulations of the oscillatory activity of the PPNa and cortex during stepping, a surrogate of gait, and stance in seven Parkinson's disease patients who received bilateral PPNa implantation for disabling freezing of gait (FOG).

Levodopa-resistant freezing of gait and executive dysfunction in Parkinson's disease.

We examined executive functioning in patients with Parkinson's disease exhibiting, or not, levodopa-resistant freezing of gait (L-FOG). 38 advanced-stage patients with L-FOG were identified in a consecutive series of 400 patients. They were matched with 38 patients without L-FOG.