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Bulbar dysfunction is common in Parkinson's disease (PD) with more than 80% of affected individuals developing dysphagia during the course of the disease. Symptoms can begin in the preclinical stage and individuals may remain clinically asymptomatic for years. Furthermore, patients may be unaware of swallowing changes, which contributes to the difference between the prevalence of self-reported dysphagia and deficits identified during instrumental evaluations. Dysphagia is underrecognized and contributes to the development of aspiration pneumonia which is the leading cause of death in PD. Dysphagia in PD is complex and not completely understood. Both dopaminergic and nondopaminergic pathways likely underpin dysphagia.This comprehensive review will cover the epidemiology, pathophysiology, clinical evaluation, and expert management of dysphagia and aspiration in patients with PD.A multidisciplinary team approach is important to properly identify and manage PD dysphagia. Regular clinical screenings with objective instrumental assessments are necessary for early detection of dysphagia. Studies are needed to better understand the mechanism(s) involved in PD dysphagia, establish markers for early detection and progression, and develop evidence-based treatment options.

INTRODUCTION: Essential tremor (ET) is a common movement disorder with an estimated prevalence of 0.9% worldwide. Deep brain stimulation (DBS) is an established therapy for medication refractory and debilitating tremor. With the arrival of next generation technology, the implementation and delivery of DBS has been rapidly evolving. This review will highlight the current applications and constraints for DBS in ET. AREAS COVERED: The mechanism of action, targets for neuromodulation, next generation guidance techniques, symptom specific applications, and long-term efficacy will be reviewed. EXPERT OPINION: The posterior subthalamic area and zona incerta are alternative targets to thalamic DBS in ET. However, they may be associated with additional stimulation induced side effects. Novel stimulation paradigms and segmented electrodes provide innovative approaches to DBS programming and stimulation induced side effects.

We describe a patient who presented with subacute ascending numbness who we diagnosed with nitrous oxide toxicity from recreational drug abuse. Characteristic neuroimaging is presented and the diagnostic process for this condition is reviewed.

Introduction: Deep brain stimulation (DBS) has become a standard therapy for the treatment of select cases of medication refractory essential tremor and Parkinson’s disease however the effectiveness and long-term outcomes of DBS in other uncommon and complex tremor syndromes has not been well established. Traditionally, the ventralis intermedius nucleus (VIM) of the thalamus has been considered the main target for medically intractable tremors; however alternative brain regions and improvements in stereotactic techniques and hardware may soon change the horizon for treatment of complex tremors. Areas covered: In this article, we conducted a PubMed search using different combinations between the terms ‘Uncommon tremors’, ‘Dystonic tremor’, ‘Holmes tremor’ ‘Midbrain tremor’, ‘Rubral tremor’, ‘Cerebellar tremor’, ‘outflow tremor’, ‘Multiple Sclerosis tremor’, ‘Post-traumatic tremor’, ‘Neuropathic tremor’, and ‘Deep Brain Stimulation/DBS’. Additionally, we examined and summarized the current state of evolving interventions for treatment of complex tremor syndromes. Expert c ommentary: Recently reported interventions for rare tremors include stimulation of the posterior subthalamic area, globus pallidus internus, ventralis oralis anterior/posterior thalamic subnuclei, and the use of dual lead stimulation in one or more of these targets. Treatment should be individualized and dictated by tremor phenomenology and associated clinical features.

Some of the behavioral disorders associated with Parkinson's disease (PD), such as the reduced magnitude of actions (hypometria) may be related to an impairment in cognitive disengagement. A reduced ability to disengage attention from previous sensory stimuli will alter perception with a reduced range of estimated stimulus magnitudes (contraction to the mean). To test this disengagement hypothesis, participants with PD were tested to learn whether they had abnormal sensory perception with overestimation of the relative magnitude of weaker tactile stimuli and underestimation of the relative magnitude of stronger tactile stimuli in relation to a reference stimulus.The participants were 12 people with PD and 12 healthy adults. Test stimuli were applied to the palm using Semmes-Weinstein monofilaments (SWM) of 6 magnitudes, 3 greater and 3 less than a standard stimulus. In each trial, after being stimulated with the reference (standard) stimulus, a test monofilament was applied, and the participant was asked to provide a numerical estimate of the magnitude of the second stimulus relative to the standard.Compared to the control group, participants with PD overestimated the magnitudes of the tactile stimuli below the standard stimulus and underestimated the magnitudes of stimuli above the standard stimulus.These results demonstrate that people with PD likely have a reduced ability to estimate the relative magnitudes of tactile sensory stimuli. Whereas deafferentation would alter perception in one direction, the impairment of these participants with PD may result from a disorder of disengagement, and disorders of disengagement are often due to frontal-executive dysfunction.

Deep brain stimulation (DBS) is an accepted therapy for appropriately selected patients with movement disorders and psychiatric disease. The recent advances in lead technology and the advent of novel stimulation parameters have spurred a number of improvements that will likely be implemented in the clinical setting. Although the mechanisms and biology of DBS remain poorly understood, the progress in our understanding of network level dysfunction has driven the introduction of a variety of new targets and approaches to the treatment of human disease. Here we summarize the recent advances in novel stimulation patterns and customized field shaping. We also review new targets, novel applications of DBS and the immediate and long-term horizon for this therapy.

Poststroke central pain (PSCP) can be a debilitating medication-refractory disorder. We report a single case where right unilateral ventral capsule/ventral striatum (VC/VS) deep brain stimulation was used to treat PSCP and inadvertently induced a smile without euphoria. The patient was a 69 year-old woman who had a stroke with resultant dysesthesia and allodynia in her left hemibody and also a painful left hemibody dystonia. In her case, VC/VS stimulation induced a smile phenomenon, but without a euphoric sensation. This phenomenon was different from the typical smile responses we have observed in obsessive-compulsive disorder cases. This difference was considered to be possibly attributable to impairment in the emotional smile pathway.

Surgical therapy for treatment-resistant obsessive compulsive disorder (OCD) remains an effective option for well-selected patients managed within a multidisciplinary setting. Historically, lesions within the limbic system have been used to control both obsessive thoughts and repetitive compulsions associated with this disease. We discuss classical targets as well as contemporary neuromodulatory approaches that have been shown to provide symptomatic relief. Recently, deep brain stimulation (DBS) of the anterior limb of the internal capsule/ventral striatum received Conformité Européene (CE) mark and Food and Drug Administration (FDA) approvals for treatment of intractable OCD. Remarkably, this is the first such approval for neurosurgical intervention in a strictly psychiatric indication in modern times. This target is discussed in detail along with alternative targets currently being proposed. We close with a discussion of gamma knife capsulotomy, a modality with deep historical roots. Further directions in the surgical treatment of OCD will require better preoperative predictors of postoperative responses, optimal selection of individualized targets, and rigorous reporting of adverse events and standardized outcomes. To meet these challenges, centers must be equipped with a multidisciplinary team and patient-centered approach to ensure adequate screening and follow up of patients with this difficult-to-treat condition.

Patients with Parkinson's disease (PD) are at risk for osteoporosis. We aimed to compare male PD subjects with short disease duration (less than 5 years) to those with longer disease duration (5 to 10 years) in bone health characteristics and in bone mineral density (BMD). This current case series included male idiopathic PD patients ages 18-90 at an outpatient academic center. Outcome measures were bone mineral density and the Unified Parkinson Disease Rating Scale Motor Section (UPDRS III). Thirty-six PD patients received DEXA scans. Seventy-two percent had osteopenia or osteoporosis in at least one bone site. Reduced BMD was observed in 58.8% of the 0-5 years PD group, and in 84.2% of the 5-10 years PD group. There was no difference in the spine BMD between the 0 to 5 years and the 5 to 10 years PD groups, and no difference in femoral neck BMD between PD disease duration groups. There were no differences in UPDRS Part III scores between 0 to 5 years and the 5 to 10 years groups. Prevalence of osteoporosis and osteopenia was high in male PD subjects regardless of disease duration. Bone-health promoting/screening behaviors were found to be low. As PD patients are prone to falls, fractures, and associated comorbidities, more research should be performed to determine if a screening regimen is appropriate.

As Johansson, Garwicz, Kanje, Schouenborg, and Halldenius (2014) note, the recent success of deep brain stimulation (DBS) in treating certain conditions has prompted further investigation of the vi...

Deep brain stimulation (DBS) has recently been proven to be an effective therapy for medication-refractory symptoms of Parkinson’s disease. As the evidence base continues to evolve, many important issues have surfaced, including: what operation should be performed (brain target[s], unilateral vs bilateral, simultaneous vs staged); when to operate (how early is too early to intervene?), who should be operated on (disease duration, age, symptom profiles and the use of the interdisciplinary screening team); and finally, why to operate (the rationale of surgery vs medication/apomorphine pumps/duodopa pumps/stem cell trials/gene therapy trials). We will address each of these critical issues, as well make the argument that a tailored approach to DBS and DBS targeting will best serve each potential candidate. We will review the multiple peer-reviewed studies and we will emphasize the recently available data from randomized DBS studies. We will argue that moving away from a single DBS target (e.g., subthalamic nucleus DBS) and a single approach to DBS methodology (e.g., bilateral simultaneous operations) is a reasonable next step for the Parkinson’s disease community. Following careful interdisciplinary DBS screening, a physician–patient discussion has the potential to establish a patient-centered and symptom-specific outcome for each potential DBS candidate. The interdisciplinary DBS team can function together to formulate and to consider an optimal and tailored approach. A tailored approach will allow for the consideration of the complex and numerous variables that may contribute to a positive or negative overall DBS outcome. We will review and provide expert commentary on a potential interdisciplinary approach to selecting unilateral or alternatively bilateral subthalamic nucleus or globus pallidus internus DBS. Our approach is aimed to maximize benefit(s) and minimize risk(s) in order to best tailor therapy for an individual patient.

Parkinson's disease is commonly accompanied by cognitive issues that limit participation in activities of daily living. Unfortunately, most current treatment paradigms and pharmacotherapeutics fail to address the cognitive impairment demonstrated in this population. Mounting evidence in healthy older adults suggests that aerobic exercise may improve cognitive function. This article describes a patient with Parkinson's disease prescribed 8 weeks of aerobic exercise. Despite very high performance at baseline, the participant improved on several cognitive measures post exercise. The results of this investigation mimic the research in healthy older adults. We therefore suggest that future large scale randomized trials are warranted to evaluate the efficacy of aerobic exercise for ameliorating declines in cognitive performance in persons with PD.

Speech reaction time (SRT) was measured in a response priming protocol in 12 participants with Parkinson's disease (PD) and hypokinetic dysarthria "on" and "off" left-hemispheric deep brain stimulation (DBS). Speech preparation was measured during speech motor programming in two randomly ordered speech conditions: speech maintenance and switching. Double blind testing was completed in participants with DBS of globus pallidus pars interna (GPi) (n = 5) or subthalamic nucleus (STN) (n = 7). SRT was significantly faster in the maintenance vs switch task, regardless of DBS state. SRT was faster in the speech maintenance task "on" stimulation, while there was no difference in speech switching "on" and "off" DBS. These data suggest that left-hemispheric DBS may have differential effects on aspects of speech preparation in PD. It is hypothesized that speech maintenance improvements may result from DBS-induced cortical enhancements, while the lack of difference in switching may be related to inhibition deficits mediated by the right-hemisphere. Alternatively, DBS may have little influence on the higher level motor processes (i.e., motor planning) which it is believed the switch task engaged to a greater extent than the maintenance task.

Repetitive behavior has been increasingly reported in Parkinson's disease (PD) patients. This study evaluates the effect of Deep Brain Stimulation (DBS) treatment on existing repetitive behavior in three PD patients who underwent unilateral STN DBS surgery at the University of Florida Movement Disorders Center. No significant change in repetitive behavior was noted acutely post-surgery; however, all cases were participating less in their repetitive behavior over time. In this series, DBS surgery seemed to have no acute effect on repetitive behavior. It is difficult to ascertain whether DBS improves repetitive behavior chronically because of confounding factors in our three cases.

Autonomic symptomatology is prevalent in Parkinson's disease (PD) and impacts quality of life, yet little data exist on the presentation of autonomic dysregulation. This study measures orthostasis, constipation, and anosmia in 58 PD patients and 51 age-matched controls enrolled in the University of Florida's Movement Disorders Center. Patients had their blood pressure measured while seated and in standing position, performed the University of Pennsylvania Smell Identification Test (UPSIT), and completed a constipation survey. Our PD patients had a significantly different average decrease in systolic BP from a seated to standing position compared with their age-matched controls (5.90 mmHg (SD 17.03) vs. 2.6 mmHg (SD 11.28); p = .05). The difference in heart rate from seated to standing positions was not significant. Reflexive tachycardia was inversely proportional to levodopa equivalent daily dose (LEDD) score (p = .002). Anosmia occurred in 96.4% of the PD group and 49% of the controls (p < .001). Constipation was also more prevalent in the PD population than in the controls (67.3% vs. 21.6%; p < .001). Both anosmia and constipation were correlated with disease duration (p = .038 and .04 respectively). Our study suggests that increasing levels of dopaminergic therapy inhibits reflexive tachycardia. Furthermore, our study suggests that anosmia and constipation progress with the primary disease process.

To determine the correlations of the Useful Field of View (UFOV), compared to other clinical tests of Parkinson's disease (PD); vision; and cognition with measures of on-road driving assessments and to quantify the UFOV's ability to indicate passing/failing an on-road test in people with PD.Nineteen randomly selected people with idiopathic PD, mean age = 74.8 (6.1), 14 (73.7%) men, 18 (94.7%) Caucasians, were age-matched to 104 controls without PD. The controls had a mean age of 75.4 (6.4), 59 (56.7%) men, 96 (92.3%) Caucasians. Both groups were referred for a driving evaluation after institutional review board approval.Compared to neuropsychological and clinical tests of vision and cognition, the UFOV showed the strongest correlations (r.75, p0.05) with measures of failing a standardized road test and number of driving errors. Among PD patients, the UFOV Risk Index score of 3 (range 1-5) was established as the optimal cutoff value for passing the on-road test, with sensitivity 87 percent and specificity 82 percent, AUC = 92 percent (SE 0.61, p = .002). Similarly, the UFOV 2 (divided attention) optimum cutoff value is 223 ms (range 16-500 ms), sensitivity 87.5 percent, specificity 81.8 percent, AUC = 91 percent (SE 0.73, p = .003). The UFOV 3 (selected attention) optimal cutoff value is 273 ms (range 16-500 ms), sensitivity 75 percent, specificity 72.7 percent, AUC = 87 percent (SE 0.81, p = .007).In this pilot study among PD patients, the UFOV may be a superior screening measure (compared to other measures of disease, cognition, and vision) for predicting on-road driving performance but its rigor must be verified in a larger sample of people with PD.

Conflicting research suggests that deep brain stimulation surgery, an effective treatment for medication-refractory Parkinson's disease (PD), may lead to selective cognitive declines. We compared cognitive performance of 22 PD patients who underwent unilateral DBS to the GPi or STN to that of 19 PD controls at baseline and 12 months. We hypothesized that compared to PD controls, DBS patients would decline on tasks involving dorsolateral prefrontal cortex circuitry (letter fluency, semantic fluency, and Digit Span Backward) but not on other tasks (Vocabulary, Boston Naming Test), and that a greater proportion of DBS patients would fall below Reliable Change Indexes (RCIs). Compared to controls, DBS patients declined only on the fluency tasks. Analyses classified 50% of DBS patients as decliners, compared to 11% of controls. Decliners experienced less motor improvement than non-decliners. The present study adds to the literature through its hypothesis-driven method of task selection, inclusion of a disease control group, longer-term follow-up and use of Reliable Change. Our findings provide evidence that unilateral DBS surgery is associated with verbal fluency declines and indicate that while these changes may not be systematically related to age, cognitive or depression status at baseline, semantic fluency declines may be more common after left-sided surgery. Finally, use of Reliable Change highlights the impact of individual variability and indicates that fluency declines likely reflect significant changes in a subset of patients who demonstrate a poorer surgical outcome overall.

X-Linked Dystonia-Parkinsonism (XDP or "Lubag") is a progressive neurodegenerative disorder unique to the Island of Panay in the Philippines. Imaging and autopsy studies have suggested involvement of the caudate and putamen in late stages. Because the clinical presentation of patients with XDP resembles that of patients with Parkinson disease or dystonia, it is reasonable to predict the neuropsychological profile might be similar; however, the neuropsychological profile of a XDP patient has not previously been published. We present the neuropsychological findings of a 67-year-old gentleman with a 10-year history of XDP who presented with parkinsonian and dystonic symptoms. He was evaluated for suitability for deep brain stimulation surgery. Neuropsychological findings demonstrated diffuse impairment involving memory, visuospatial, language, and executive functioning.

Patients with Parkinson's disease (PD) have dysfunction in frontal-basal ganglia networks. Many of these patients have difficulties with mental processing speed, response inhibition, and shifting between different conceptual sets, suggesting frontal-executive dysfunction. Since frontal lobe dysfunction is associated with disengagement deficits such as perseveration and echopraxia we wanted to learn if patients with PD demonstrated defective response inhibition. Using a brief clinical test called the crossed response inhibition (CRI) task we assessed patients with PD (n = 17), and a group of age matched controls (n = 30). In addition to the CRI, subjects were asked to perform two tests of frontal lobe function: verbal word fluency, anti-saccade test. In the CRI task, patients are instructed to lift the hand opposite to the one the examiner touches. An error is scored whenever the patient makes any movement of the touched (ipsilateral) extremity after stimulation (from shoulder to fingers). The task is performed with the patient's eyes closed. Whereas no differences were found between PD and control subjects on the verbal fluency or anti-saccade tasks, PD patients made significantly more errors on the CRI than did controls. Subsequent analyses found no difference in performance associated with the laterality (asymmetry) of PD symptoms or signs. In addition, there was no difference between PD patients' CRI performance when they were "on" their dopaminergic medications versus when they were "off" these medicines. Based on these findings, it appears that PD is associated with a disengagement-inhibition defect that is not induced by a dopaminergic deficit. In addition, the CRI task might be a brief sensitive bedside task for evaluating frontal dysfunction in PD.

Several studies have related pathological gambling in PD to dopamine agonist therapy. A mail-in survey was sent to PD patients seen at the University of Florida Movement Disorders Center to determine gambling frequency and behavior, and any lifestyle or environmental factors associated with compulsive gambling in PD. 462 surveys were sent and 127 completed surveys were returned, of which ten were from patients who met criteria for compulsive gambling. All ten were taking dopamine agonists coincident with the compulsive gambling. Compulsive gamblers were younger, and psychological distress measures revealed that compulsive gamblers exhibited higher levels of anxiety, anger, and confusion. Thus in this cohort, we have uncovered the several characteristics of the most likely PD compulsive gambler, namely: (young) age, “angry”, “anxious”, and using a (dopamine) agonist.

Deep brain stimulation (DBS) now plays an important role in the treatment of Parkinson's disease, tremor, and dystonia. DBS may also have a role in the treatment of other disorders such as obsessive-compulsive disorder, Tourette's syndrome, and depression. The neuropsychologist plays a crucial role in patient selection, follow-up, and management of intra-operative and post-operative effects (Pillon, 2002; Saint-Cyr & Trepanier, 2000). There is now emerging evidence that DBS can induce mood, cognitive, and behavioral changes. These changes can have dramatic effects on patient outcome. There have been methodological problems with many of the studies of DBS on mood, cognition, and behavior. The neuropsychologist needs to be aware of these issues when following up patients, and constructing future studies. Additionally, this article will review all aspects of the DBS procedure that can result in mood, cognitive, and behavioral effects and what role(s) the neuropsychologist should play in screening and follow-up.

This review addresses the literature surrounding Parkinson's disease (PD) and mild cognitive impairment (MCI). It discusses the neuropsychological, pharmaceutical, and pathological overlap, the socioeconomic impact of PD and MCI, and the value of recognizing, understanding, and treating MCI in PD. It is concluded from this review that MCI in PD does exist and should be considered in clinical and research investigations. Due to the lack of accepted clinical criteria, an inclusive operating definition of MCI in PD is proposed. Research guidelines for studying the presence of MCI in PD and evaluating the efficacy of pharmaceutical interventions are also suggested.

Parkin mutations are a common cause of early-onset Parkinson’s disease. To study the clinical features and treatment responses of patients with homozygous or heterozygous Parkin mutations, we performed a retrospective chart review in six early-onset parkinsonism patients with pathogenic Parkin mutations. The clinical phenotypes observed in this cohort, all drawn from different families, were variable. All patients had a slowly progressive form of parkinsonism that responded well to dopaminergic therapy with the exception of one advanced case. Homozygous patients had an earlier age at disease onset than heterozygous patients. Two of our patients underwent bilateral deep brain stimulation (DBS) of the subthalamic nucleus or globus pallidus leading to a sustained positive response. Our observations support an earlier age of onset for homozygous cases and possible beneficial effects of DBS in Parkin-related parkinsonism.

The recent publication of Neurological Eponyms by Peter Koehler and colleagues has revived the interest in neurological eponyms and raised important questions about their use. Many investigators have contributed to the body of knowledge that defines the specialty of neurology. We honor them by associating their names with neurological diseases. The history of neurological eponyms provides us with an opportunity to reexamine the important question of who gets the credit. Additional issues have surfaced including why certain eponyms tend to stick in the literature and others disappear, as well as the important realization that lengthy modern descriptions may require name eponyms for simplification. Eponyms can be confusing as to whether they refer to a disease or a syndrome and this confusion can impact the diagnosis and treatment of patients. There is an inevitable evolution of certain eponyms as our understanding of entities expands. This paper provides an overview of neurological eponyms with the explanation of the potential reasons why names were associated with neurological diseases. These included first case reports, relating isolated cases, years of observation, defining neuroanatomy, physician sufferer, new physical examination maneuvers, academic climate, the advent of a new procedure, fame, and competition amongst investigators. Important issues have surfaced regarding sharing credit amongst investigators, name priority, crediting the wrong investigator, and lack of a defined system to award credit. Since eponym use is based on a peer dependent system, each neurologist must make a more critical appraisal of who gets the credit and understand the differences between diseases and syndromes in order to better preserve neurological history.

Christine A Cooper, Armon Jadidian, Michelle Paggi, Janet Romrell, Michael S Okun, et alDepartment of Neurology, University of Florida, Gainesville, FL, USAAbstract: This study investigates the prevalence and demographic characteristics of hypersexuality in Parkinson’s disease (PD). Impulse control disorders in PD patients have been associated with dopamine agonist therapy. Moreover, hypersexuality and pathological gambling have been associated with males, while females may be inherently thought to be more likely to participate in compulsive shopping and binge-eating behaviors. In this study, a screening mail-in survey was sent to all PD patients at a single Movement Disorders Center. One hundred forty one of 400 (35.3%) research packets were returned completed. Fifteen of 141 patients met initial screening criteria for hypersexual behavior. After detailed interview, only 6/141 (4.3%) of PD patients met criteria for pathologic hypersexual behavior. These behaviors included: compulsive masturbation, prostitution, and paraphilias. Patients with a younger age of PD onset were more likely to exhibit hypersexual behavior. Unlike previous report, no significant association was found between hypersexuality and gender or dopamine agonist use. Rather, this study suggests that physicians should be vigilant for hypersexual behavior in all PD patients, regardless of gender and PD medication regimen. Ultimately, given the innate sensitivity of the topic and survey limitations, it is very likely that hypersexual behavior in our cohort, as it is in the general PD population, has been under-reported.Keywords: Parkinson’s disease, hypersexuality, impulsive behavior, dopamine agonists