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Presentation

History

Onset of motor signs in Parkinson disease is typically asymmetric, with the most common initial finding being an asymmetric resting tremor in an upper extremity. Over time, patients notice symptoms related to progressive bradykinesia, rigidity, and gait difficulty. The first affected arm may not swing fully when walking, and the foot on the same side may scrape the floor. Over time, axial posture becomes progressively flexed and strides become shorter.

Some nonmotor symptoms commonly precede motor signs in Parkinson disease. Most Parkinson disease patients have a substantial reduction in olfactory function (smell) by the time motor signs emerge. However, either this is not noticed by the patients or patients may not realize that it is part of the disease. Another common premotor symptom is rapid eye movement (REM) behavior disorder (RBD). In this condition, individuals exhibit movements during REM sleep that are often described as hitting or kicking motions. There are also a number of midlife risk factors for the later development of Parkinson disease. These include constipation and excessive daytime sleepiness, although they are far from specific for Parkinson disease.

In a British study, the frequency of nonmotor symptoms in 159 patients with newly diagnosed Parkinson’s disease was found to be significantly greater than that in 99 healthy age-matched control patients (mean, 8.4 vs 2.8).^[24]The most commonly experienced nonmotor symptoms in patients with early Parkinson disease in this study included the following^[25]:

Excessive saliva
Forgetfulness
Urinary urgency
Hyposmia
Constipation

Initial clinical symptoms in Parkinson disease include the following:

Tremor
A subtle decrease in dexterity; for example, a lack of coordination with activities such as playing golf or dressing (about 20% of patients first experience clumsiness in one hand)
Decreased arm swing on the first-involved side
Soft voice
Decreased facial expression
Sleep disturbances
RBD, in which there is a loss of normal atonia during REM sleep: In one study, 38% of 50-year-old men with RBD and no neurologic signs went on to develop parkinsonism^[26]; patients “act out their dreams” and may kick, hit, talk, or cry out in their sleep
Decreased sense of smell
Symptoms of autonomic dysfunction, including constipation, sweating abnormalities, sexual dysfunction, and seborrheic dermatitis
A general feeling of weakness, malaise, or lassitude
Depression or anhedonia
Slowness in thinking

Common early motor signs of Parkinson disease include tremor, bradykinesia, rigidity, and dystonia.

Tremor

Although tremor is the most common initial symptom in Parkinson disease, occurring in approximately 70% of patients, it does not have to be present to make the diagnosis. Tremor is most often described by patients as shakiness or nervousness and usually begins in one upper extremity and initially may be intermittent. Upper extremity tremor generally begins in the fingers or thumb, but it can also start in the forearm or wrist. After several months or years, the tremor may spread to the ipsilateral lower extremity or the contralateral upper extremity before becoming more generalized; however, asymmetry is usually maintained.

Tremor can vary considerably, emerging only with stress, anxiety, or fatigue. Classically, the tremor of Parkinson disease is a resting tremor (occurring with the limb in a resting position) and disappears with action or use of the limb, but this is not seen in all patients. Initially, the tremor may be noticed during activities such as eating or reading a newspaper. Although Parkinson disease is a rare cause of tremor affecting the head or neck, tremors of the chin, lip, or tongue are not uncommon. As with other tremors, the amplitude increases with stress and resolves during sleep.

Bradykinesia

Bradykinesia refers to slowness of movement. Symptoms of bradykinesia are varied and can be described by patients in different ways. These may include a subjective sense of weakness, without true weakness on physical examination; loss of dexterity, sometimes described by patients as the "message not getting to the limb"; fatigability; or achiness when performing repeated actions.

Facial bradykinesia is characterized by decreased blink rate and facial expression. Speech may become softer, less distinct, or more monotonal. In more advanced cases, speech is slurred, poorly articulated, and difficult to understand. Drooling is an uncommon initial symptom in isolation but is reported commonly (especially nighttime drooling) later in the disease course.

Truncal bradykinesia results in slowness or difficulty in rising from a chair, turning in bed, or walking. If walking is affected, patients may take smaller steps and gait cadence is reduced. Some patients experience a transient inability to walk, as though their feet are frozen to the floor. This "freezing" is seen commonly in patients with more advanced disease; it is more prominent as patients attempt to navigate doorways or narrow areas and can result in patients getting trapped behind furniture or being unable to cross a door threshold easily.

In the upper extremities, bradykinesia can cause small, effortful handwriting (ie, micrographia) and difficulty using the hand for fine dexterous activities such as using a key or kitchen utensils. In the lower extremities, unilateral bradykinesia commonly causes scuffing of that foot on the ground, as it is not picked up during leg swing. This may also be described as dragging of one leg.

Rigidity

Some patients may describe stiffness in the limbs, but this may reflect bradykinesia more than rigidity. Occasionally, individuals may describe a feeling of ratchety stiffness when moving a limb, which may be a manifestation of cogwheel rigidity.

Dystonia

Dystonia is a common initial symptom in young-onset Parkinson disease, which is defined as symptom onset before age 40 years. Dystonia in Parkinson disease commonly consists of a foot involuntary turning in (inversion) or down (plantar flexion), often associated with cramping or aching in the leg. Dorsiflexion of the big toe may also occur. Another common dystonia in Parkinson disease is adduction of the arm and elbow, causing the hand to rest in front of the abdomen or chest. Dystonic postures can wax and wane, occurring with fatigue or exertion.

Whether stooped posture is due to truncal dystonia is a matter of debate. One study suggests that the stooped posture may be due to vertebral fractures resulting from vitamin D deficiency with compensatory hyperparathyroidism.^[27]Vitamin D supplementation may reduce the risk for stooped posture.

Physical Examination

There are 4 cardinal signs of Parkinson disease, with 2 of the first 3 listed below required to make the clinical diagnosis. The fourth cardinal sign, postural instability (balance difficulty), emerges late in the disease, usually after 8 years or more.

Resting tremor
Rigidity
Bradykinesia
Postural instability

Resting tremor

Resting tremor is assessed by having patients relax their arms in their lap while in a seated position. Having patients count aloud backward from 10 may help bring out the tremor. The arms should also be observed in an outstretched position to assess postural tremor, and kinetic tremor (tremor with voluntary movement) can be observed during the finger-to-nose test. Although a resting tremor is the tremor characteristic of Parkinson disease, many Parkinson disease patients also have some postural and/or kinetic tremor.

Rigidity

Rigidity refers to an increase in resistance to passive movement about a joint. The resistance can be either smooth (lead pipe) or oscillating (cogwheeling). Cogwheeling is thought to reflect tremor rather than rigidity and may be present with tremors not associated with an increase in tone (ie, essential tremor). Rigidity is usually tested by flexing and extending the patient's relaxed wrist and can be made more obvious by having the patient perform voluntary movements, such as tapping, with the contralateral limb.

Bradykinesia

Bradykinesia refers to slowness of movement but also includes reduced spontaneous movements and decreased amplitude of movement. Bradykinesia is also expressed as micrographia (small handwriting), hypomimia (decreased facial expression), decreased blink rate, and hypophonia (soft speech). Thus, the patient’s blink rate and facial expression should be observed.

In addition, speed and amplitude of movements are assessed by having the patient open his or her hand (each limb is assessed individually) and tap his or her thumb and index finger repetitively, trying to perform the movement as big and as fast as possible. Similarly, the patient should be asked to tap the toes of each foot as big and as fast as possible. Finally, the patient should be asked to arise from a seated position with the arms crossed to assess the ability to arise from a chair. The patient is then observed while walking to assess stride length and speed, as well as arm swing.

Postural instability

Postural instability refers to imbalance and loss of righting reflexes. Its emergence in a patient with Parkinson disease is an important milestone, because it is poorly amenable to treatment and a common source of disability in late disease. Postural stability is typically assessed by having patients stand with their eyes open and then pulling their shoulders back toward the examiner. Patients are told to be ready for the displacement and to regain their balance as quickly as possible. Taking 1 or 2 steps backward to regain balance is considered normal. The examiner should be ready to catch patients if they are unable to regain balance.

Laryngeal dysfunction and dysphagia

As the patient is speaking, the vocal loudness, intonation, and quality, including fluidity of speech and articulation, should be assessed. Sustaining vowel phonation (eg, "ah") for maximum duration, counting to 50, and reading a passage that tests articulation (eg, the rainbow passage) provide reasonable speech samples. Closely listening for reduced or diminishing loudness and intonation and increasing breathiness and hoarseness helps differentiate Parkinson disease from hyperkinetic disorders such as spasmodic dysphonia.^[28]

A soft, monotone voice, vocal tremor, poor articulation, variable speech rate, trouble with the initiation of speech, and stuttering-like qualities are all characteristics of Parkinson disease. Perhaps the most telling vocal symptom is the marked contrast between habitual vocal volume (soft and diminishing) and the patient's response to a request to increase loudness. A request to "say that again, twice as loud" often results in increased loudness, improved voice quality, and a dramatic improvement in speech intelligibility.

Dysphagia is common, especially in advanced Parkinson disease. Manifestations may range from drooling to aspiration.

An otolaryngologist can perform a more detailed assessment of laryngeal dysfunction in patients with Parkinson disease, using neurolaryngeal examination and stroboscopy. Because distortion can occur when the tongue is held forward during rigid stroboscopy, the neurolaryngeal examination is best performed by viewing the larynx with a flexible laryngoscope. The larynx is evaluated for vocal fold mobility, paresis or paralysis, coordination of movement, agility, fatigability, flexibility, and use of accessory muscles during phonation while the patient says various phrases and syllables. Hyperfunctional and hypofunctional disorders can often be differentiated by isolating the abductor and adductor muscle groups. The larynx is also visualized at rest.

Rigid stroboscopy plays a key role in the assessment of the vibratory characteristics of the vocal folds, including the presence of masses, lesions, or scar and glottic configuration abnormalities, including an elliptical closure pattern, phase asymmetry, and abnormal phase closure. Stroboscopy and neurolaryngeal examination are complementary in the evaluation of the patient with Parkinson disease. Common stroboscopy findings in Parkinson disease include true vocal fold atrophy or other evidence of glottal incompetence, including a chasing wave or a shorter closed phase.

Pooling of secretions, decreased sensation, and aspiration are also characterizations of the Parkinson disease larynx. A paralyzed vocal fold suggests Parkinson-plus syndrome (PPS) as the etiology for the parkinsonism if other aspects of the diagnosis are present.

Perez et al found that vocal tremor is present in 55% of patients with Parkinson disease.^[29]Interestingly, only 35% of patients with Parkinson disease exhibited a resting vocal cord tremor, whereas the remainder exhibited kinetic tremor. The tremor is primarily a vertical laryngeal movement. PPS was found to carry a higher incidence of vocal tremor (64%), with most tremors located in the arytenoids. The authors found no vertical laryngeal tremor in patients with PPS.^[29]

Autonomic dysfunction

Autonomic dysfunction is common in patients with Parkinson disease. Orthostatic hypotension often becomes a concern in late disease, and impaired intestinal motility can lead to constipation and, sometimes, vomiting or impaired absorption. Urinary symptoms, retention, and bladder infection can occur, and erectile dysfunction is not uncommon. In addition, many patients note episodes of sweating.

Prominent autonomic dysfunction, especially frank urinary incontinence or profound orthostatic hypotension, may suggest multiple system atrophy (MSA) rather than Parkinson disease.

Cardiopulmonary impairment

The flexed posture of patients with Parkinson disease can lead to kyphosis, cause a reduction in pulmonary capacity, and produce a restrictive lung disease pattern.

Staging

Investigators have proposed a staging system to improve the assessment of overall Parkinson disease severity. In an observational, cross-sectional study of 933 patients with Parkinson disease, Ray Chaudhuri and colleagues found a wide discrepancy between the severity of nonmotor symptoms as measured by the NonMotor Symptoms Scale (NMSS) and motor symptoms as measured by the Hoehn and Yahr scale.^{[30, 31]}The investigators proposed a staging system for nonmotor symptom burden based on NMSS scores, which was correlated with measures of disability and quality of life. The staging system rates nonmotor symptom burden (NMSB) on a scale of 0 (no NMSB) to 4 (very severe NMSB).^{[30, 31]}

Depression

Given the high prevalence of mood disorders in Parkinson disease, these patients should be screened regularly for depression. However, assessment of depression in patients with Parkinson disease is complicated by the fact that some symptoms of Parkinson disease overlap with those of depression (eg, masklike facies, insomnia, psychomotor slowing, difficulty concentrating, fatigue). Guilt and self-reproach are less prominent in depression in patients with Parkinson disease, whereas anxiety and pessimism are more prominent.

Dementia

Hoops et al found that in Parkinson disease, the Montreal Cognitive Assessment (MoCA) is superior to the Mini-Mental State Examination (MMSE) for screening for mild cognitive impairment or dementia.^[32]MoCA and MMSE demonstrated similar overall discriminant validity for detection of any cognitive disorder, but as a screening instrument, MoCA was better than MMSE (64% vs 54% correct diagnoses).^[32]

The prevalence of dementia in Parkinson disease ranges from 20-40%, with the disease conferring a 2- to 6-fold increased risk compared with control populations.^[33]Many patients with Parkinson disease have some executive function impairment, even early in the disease.^[33]Substantial cognitive impairment and dementia typically occur 8 years or more after the onset of motor features.

Dementia generally occurs late in Parkinson disease; substantial cognitive dysfunction within 1 year of onset of motor features suggests a diagnosis of Lewy body disease, a disease closely related to Parkinson disease and marked by the presence of cortical Lewy bodies. In the affected age group, comorbidity with other neurodegenerative disorders, particularly Alzheimer disease and cerebrovascular disease, is common. The relatively high prevalence of depression in patients with Parkinson disease is another confounder in the diagnosis of Parkinson disease dementia.

Executive function, short-term memory, and visuospatial ability may be impaired in patients with Parkinson disease dementia, but aphasia is not present. In a long-term Australian study that compared neuropsychologic measures between patients with Parkinson disease who had early dementia (< 10 years of disease onset) and those with late dementia, investigators reported that dementia in parkinsonism appears to occur at about age 70 years regardless of the time of onset of Parkinson disease.^[34]However, although early and late dementia had similar effects in cognitive domains, individuals with early onset of parkinsonism had a preserved linguistic ability before the onset of dementia.^[34]

Atypical Parkinsonisms

Atypical parkinsonisms, or Parkinson-plus syndromes, are primary neurodegenerative disorders that have parkinsonian features and are associated with complex clinical presentations that reflect degeneration in various neuronal systems. Patients with atypical parkinsonisms typically have a worse prognosis than those with Parkinson disease, and atypical parkinsonisms respond poorly to standard anti-Parkinson disease treatments.

(For more information, see Parkinson-Plus Syndromes for detailed information regarding clinical clues, workup, differential diagnosis, and treatment of atypical parkinsonisms, including multiple system atrophy, progressive supranuclear palsy, parkinsonism-dementia-amyotrophic lateral sclerosis complex, corticobasal ganglionic degeneration, and diffuse Lewy body disease.)

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Media Gallery

Schematic representation of the basal ganglia - thalamocortical motor circuit and its neurotransmitters in the normal state. From Vitek J. Stereotaxic surgery and deep brain stimulation for Parkinson disease and movement disorders. In: Watts RL, Koller WC, eds. Movement Disorders: Neurologic Principles and Practice. New York: McGraw-Hill, 1997:240. Copyright, McGraw-Hill Companies, Inc. Used with permission.
Schematic representation of the basal ganglia - thalamocortical motor circuit and the relative change in neuronal activity in Parkinson disease. From Vitek J. Stereotaxic surgery and deep brain stimulation for Parkinson disease and movement disorders. In: Watts RL, Koller WC, eds. Movement Disorders: Neurologic Principles and Practice. New York: McGraw-Hill, 1997:241. Used with kind permission. Copyright, McGraw-Hill Companies, Inc.
Parkinson disease diary. The patient or caregiver should place 1 check mark in each half-hour time slot to indicate the patient's predominant response during most of that period. The goal of therapeutic management is to minimize off time and on time with troublesome dyskinesia. Copyright Robert Hauser, 1996. Used with permission.
Stages in the development of Parkinson disease (PD)-related pathology (path.). Adapted from Braak H, Ghebremedhin E, Rub U, Bratzke H, Del Tredici K. Stages in the development of Parkinson's disease-related pathology. Cell Tissue Res. 2004 Oct;318(1):121-34.
Schematic diagram of the basal ganglia circuitry. Represented are the following: inhibitory (red arrows) and excitatory (green arrows) projections between the motor cortex, the putamen, the globus pallidus pars externa (GPe) and globus pallidus pars interna (GPi), the subthalamic nucleus (STN), the substantia nigra pars reticulata (SNr) and substantia nigra pars compacta (SNc), and the ventrolateral thalamus (VL). D1 and D2 indicate the direct (regulated by dopamine D1 receptors) and indirect (regulated by dopamine D2 receptors) pathways, respectively.
Sagittal section, 12 mm lateral of the midline, demonstrating the subthalamic nucleus (STN) (lavender). The STN is one of the preferred surgical targets for deep brain stimulation to treat symptoms of advanced Parkinson disease.
The deep brain stimulating lead is equipped with 4 electrode contacts, each of which may be used, alone or in combination, for therapeutic stimulation.
Axial, fast spin-echo inversion recovery magnetic resonance image at the level of the posterior commissure. The typical target for placing a thalamic stimulator is demonstrated (cross-hairs).
Implantation of the deep brain stimulation (DBS) lead.
Insertion of an electrode during deep brain stimulation for Parkinson disease.
Postoperative coronal magnetic resonance image (MRI) demonstrating desired placement of bilateral subthalamic nuclei-deep brain stimulation (STN-DBS) leads.
Radiograph of the skull depicting a deep brain stimulator and leads in a patient with Parkinson disease.
Lewy bodies in the locus coeruleus from a patient with Parkinson disease.
A: Schematic initial progression of Lewy body deposits in the first stages of Parkinson disease (PD), as proposed by Braak and colleagues. B: Localization of the cluster of significant volume reduction in PD compared with health control subjects. The significant cluster located in the medulla oblongata/pons is superimposed as a red blob on the mean normalized anatomic scan of all participants. The axial and sagittal sections are centered on the peak of significance (–1; –36; –49). This image using voxel-based morphometry (VBM), which searched for regional atrophy in idiopathic PD by comparing a group of subjects with the disease and a group of healthy controls. Jubault T, Brambati SM, Degroot C, et al. Regional brain stem atrophy in idiopathic Parkinson's disease detected by anatomical MRI. PLoS ONE. 2009;4(12):e8247.
Gross comparison of the appearance of the substantia nigra between a normal brain and a brain affected by Parkinson disease. Note the well-pigmented substantia nigra in the normal brain specimen on the left. In the brain of a Parkinson disease patient on the right, loss of pigmented substantia nigra due to depopulation of pigmented neurons is observed.
Lewy bodies are intracytoplasmic eosinophilic inclusions, often with halos, that are easily seen in pigmented neurons, as shown in this histologic slide. They contain polymerized alpha-synuclein; therefore, Parkinson disease is a synucleinopathy.

of 16

Author

Robert A Hauser, MD, MBA Professor of Neurology, Molecular Pharmacology and Physiology, Director, USF Parkinson's Disease and Movement Disorders Center, National Parkinson Foundation Center of Excellence, Byrd Institute, Clinical Chair, Signature Interdisciplinary Program in Neuroscience, University of South Florida College of Medicine

Robert A Hauser, MD, MBA is a member of the following medical societies: American Academy of Neurology, American Medical Association, American Society of Neuroimaging, International Parkinson and Movement Disorder Society

Disclosure: Received consulting fee from Cerecor for consulting; Received consulting fee from L&M Healthcare for consulting; Received consulting fee from Cleveland Clinic for consulting; Received consulting fee from Heptares for consulting; Received consulting fee from Gerrson Lehrman Group for consulting; Received consulting fee from Indus for consulting; Received consulting fee from University of Houston for consulting; Received consulting fee from AbbVie for consulting; Received consulting fee from Adama.

Coauthor(s)

Kelly E Lyons, PhD Research Professor of Neurology, Director of Research and Education, Parkinson’s Disease and Movement Disorder Center, University of Kansas Medical Center

Kelly E Lyons, PhD is a member of the following medical societies: American Academy of Neurology, International Parkinson and Movement Disorder Society

Disclosure: Received honoraria from Novartis for speaking and teaching; Received honoraria from Teva Neuroscience for speaking and teaching; Received honoraria from St Jude Medical for board membership.

Theresa A McClain, RN, MSN, ARNP-BC Advanced Registered Nurse Practitioner and Investigator, Parkinson’s Disease and Movement Disorders Center, University of South Florida College of Medicine

Theresa A McClain, RN, MSN, ARNP-BC is a member of the following medical societies: Sigma Theta Tau International

Disclosure: Received consulting fee from Teva for consulting; Received consulting fee from Schering Plough for consulting; Received consulting fee from Biotie for consulting; Received consulting fee from Novartis for consulting.

Rajesh Pahwa, MD Professor of Neurology, Director, Parkinson Disease and Movement Disorder Center, Department of Neurology, University of Kansas Medical Center

Rajesh Pahwa, MD is a member of the following medical societies: American Academy of Neurology, International Parkinson and Movement Disorder Society

Disclosure: Nothing to disclose.

Chief Editor

Selim R Benbadis, MD Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, Tampa General Hospital, University of South Florida Morsani College of Medicine

Selim R Benbadis, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Sleep Medicine, American Clinical Neurophysiology Society, American Epilepsy Society, American Medical Association

Disclosure: Serve(d) as a director, officer, partner, employee, advisor, consultant or trustee for: Bioserenity, Ceribell, Eisai, Jazz, LivaNova, Neurelis, Neuropace, SK life science, Sunovion, Takeda, UCB<br/>Serve(d) as a speaker or a member of a speakers bureau for: Aquestive, Bioserenity, Eisai, Jazz, LivaNova, Neurelis, SK life science, Stratus, Sunovion, UCB<br/>Received research grant from: Cerevel Therapeutics, Ovid Therapeutics, Neuropace, Greenwich Jazz, SK Life Science, Xenon Pharmaceuticals, UCB, Marinus, Neuroelectrics Corporation, Longboard, Janssen, Equilibre Biopharmaceuticals.

Acknowledgements

Ron L Alterman, MD Associate Professor of Neurosurgery, Mount Sinai School of Medicine; Consulting Surgeon, Department of Neurosurgery, Mount Sinai School of Medicine, Elmhurst Hospital, and Walter Reed Army Medical Center

Ron L Alterman, MD is a member of the following medical societies: Alpha Omega Alpha, American Association of Neurological Surgeons, Congress of Neurological Surgeons, Medical Society of the State of New York, and New York County Medical Society

Disclosure: Nothing to disclose.

Heather S Anderson, MD Assistant Professor, Staff Neurologist, Department of Neurology, Alzheimer and Memory Center, University of Kansas Medical Center

Heather S Anderson, MD is a member of the following medical societies: American Academy of Neurology

Disclosure: Nothing to disclose.

Jeff Blackmer, MD, FRCP(C) Associate Professor, Medical Director, Neurospinal Service, Division of Physical Medicine and Rehabilitation, The Rehabilitation Centre, University of Ottawa Faculty of Medicine; Executive Director, Office of Ethics, Canadian Medical Association

Jeff Blackmer, MD, FRCP(C) is a member of the following medical societies: American Paraplegia Society, Canadian Association of Physical Medicine and Rehabilitation, Canadian Medical Association, and Royal College of Physicians and Surgeons of Canada

Disclosure: Nothing to disclose.

Thomas L Carroll, MD Assistant Professor, Department of Otolaryngology-Head and Neck Surgery, Tufts University School of Medicine and Director, The Center for Voice and Swallowing, Tufts Medical Center

Thomas L Carroll, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Otolaryngology-Head and Neck Surgery, American Bronchoesophagological Association, American Laryngological Association, and American Medical Association

Disclosure: Merz aesthetics inc. Consulting fee Speaking and teaching

Richard J Caselli, MD Professor, Department of Neurology, Mayo Medical School, Rochester, MN; Chair, Department of Neurology, Mayo Clinic of Scottsdale

Richard J Caselli, MD is a member of the following medical societies: American Academy of Neurology, American Association of Neuromuscular and Electrodiagnostic Medicine, American Medical Association, American Neurological Association, and Sigma Xi

Disclosure: Nothing to disclose.

Arif I Dalvi, MD Director, Movement Disorders Center, NorthShore University HealthSystem, Clinical Associate Professor of Neurology, University of Chicago Pritzker Medical School

Arif I Dalvi, MD is a member of the following medical societies: European Neurological Society and Movement Disorders Society

Disclosure: Nothing to disclose.

Nestor Galvez-Jimenez, MD, MSc, MHA Chairman, Department of Neurology, Program Director, Movement Disorders, Department of Neurology, Division of Medicine, Cleveland Clinic Florida

Nestor Galvez-Jimenez, MD, MSc, MHA is a member of the following medical societies: American Academy of Neurology, American College of Physicians, and Movement Disorders Society

Disclosure: Nothing to disclose.

Stephen T Gancher, MD Adjunct Associate Professor, Department of Neurology, Oregon Health Sciences University

Stephen T Gancher, MD is a member of the following medical societies: American Academy of Neurology, American Neurological Association, and Movement Disorders Society

Disclosure: Nothing to disclose.

Michael Hoffmann, MBBCh, MD, FCP(SA), FAAN, FAHA Professor of Neurology, University of Central Florida College of Medicine; Director of Cognitive Neurology, Director of Stroke Program, James A Haley Veterans Affairs Hospital

Michael Hoffmann, MBBCh, MD, FCP(SA), FAAN, FAHA is a member of the following medical societies: American Academy of Neurology, American Headache Society, American Heart Association, and American Society of Neuroimaging

Disclosure: Nothing to disclose.

Daniel H Jacobs MD, FAAN, Associate Professor of Neurology, University of Florida College of Medicine; Director for Stroke Services, Orlando Regional Medical Center

Daniel H Jacobs is a member of the following medical societies: American Academy of Neurology, American Society of Neurorehabilitation, and Society for Neuroscience

Disclosure: Teva Pharmaceutical Grant/research funds Consulting; Biogen Idex Grant/research funds Independent contractor; Serono EMD Royalty Speaking and teaching; Pfizer Royalty Speaking and teaching; Berlex Royalty Speaking and teaching

Robert M Kellman, MD Professor and Chair, Department of Otolaryngology and Communication Sciences, State University of New York Upstate Medical University

Robert M Kellman, MD is a member of the following medical societies: American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, American College of Surgeons, American Medical Association, American Neurotology Society, American Rhinologic Society, American Society for Head and Neck Surgery, Medical Society of the State of New York, and Triological Society

Disclosure: GE Healthcare Honoraria Review panel membership; Revent Medical Honoraria Review panel membership

Milton J Klein, DO, MBA Consulting Physiatrist, Heritage Valley Health System-Sewickley Hospital and Ohio Valley General Hospital

Milton J Klein, DO, MBA is a member of the following medical societies: American Academy of Disability Evaluating Physicians, American Academy of Medical Acupuncture, American Academy of Osteopathy, American Academy of Physical Medicine and Rehabilitation, American Medical Association, American Osteopathic Association, American Osteopathic College of Physical Medicine and Rehabilitation, American Pain Society, and Pennsylvania Medical Society

Disclosure: Nothing to disclose.

Kat Kolaski, MD Assistant Professor, Departments of Orthopedic Surgery and Pediatrics, Wake Forest University School of Medicine

Kat Kolaski, MD is a member of the following medical societies: American Academy for Cerebral Palsy and Developmental Medicine and American Academy of Physical Medicine and Rehabilitation

Disclosure: Nothing to disclose.

Jose G Merino, MD Medical Director, Suburban Hospital Stroke Program

Jose G Merino, MD is a member of the following medical societies: American Heart Association and American Stroke Association

Disclosure: Nothing to disclose.

Arlen D Meyers, MD, MBA Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine

Arlen D Meyers, MD, MBA is a member of the following medical societies: American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, and American Head and Neck Society

Disclosure: Covidien Corp Consulting fee Consulting; US Tobacco Corporation Unrestricted gift Unknown; Axis Three Corporation Ownership interest Consulting; Omni Biosciences Ownership interest Consulting; Sentegra Ownership interest Board membership; Syndicom Ownership interest Consulting; Oxlo Consulting; Medvoy Ownership interest Management position; Cerescan Imaging Honoraria Consulting; GYRUS ACMI Honoraria Consulting

Lorraine Ramig, PhD Professor, Department of Speech Language Hearing Sciences, University of Colorado at Boulder; Senior Scientist, National Center for Voice and Speech (NCVS); Adjunct Professor, Department of Biobehavior, Columbia University Teacher's College

Disclosure: Nothing to disclose.

Alan D Schmetzer, MD Professor Emeritus, Interim Chairman, Vice-Chair for Education, Associate Residency Training Director in General Psychiatry, Fellowship Training Director in Addiction Psychiatry, Department of Psychiatry, Indiana University School of Medicine; Addiction Psychiatrist, Midtown Mental Health Cener at Wishard Health Services

Alan D Schmetzer, MD is a member of the following medical societies: American Academy of Addiction Psychiatry, American Academy of Clinical Psychiatrists, American Academy of Psychiatry and the Law, American College of Physician Executives, American Medical Association, American Neuropsychiatric Association, American Psychiatric Association, and Association for Convulsive Therapy

Disclosure: Eli Lilly & Co. Grant/research funds Other

Roy Sucholeiki, MD Director, Comprehensive Seizure and Epilepsy Program, The Neurosciences Institute at Central DuPage Hospital

Roy Sucholeiki, MD is a member of the following medical societies: American Academy of Neurology, American Epilepsy Society, and American Neuropsychiatric Association

Disclosure: Nothing to disclose.

Margaret M Swanberg, DO Assistant Professor of Neurology, Uniformed Services University; Chief of Neurobehavior Service, Walter Reed Army Medical Center; Assistant Chief, Department of Neurology, Walter Reed Army Medical Center

Margaret M Swanberg, DO is a member of the following medical societies: American Academy of Neurology and American Neuropsychiatric Association

Disclosure: Nothing to disclose.

Michele Tagliati, MD Associate Professor, Department of Neurology, Mount Sinai School of Medicine; Division Chief of Movement Disorders, Mount Sinai Medical Center

Michele Tagliati, MD is a member of the following medical societies: American Academy of Neurology, American Medical Association, and Movement Disorders Society

Disclosure: Nothing to disclose.

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Medscape Salary Employment

B Viswanatha, MBBS, MS, DLO Professor of Otolaryngology (ENT), Chief of ENT III Unit, Sri Venkateshwara ENT Institute, Victoria Hospital, Bangalore Medical College and Research Institute; PG and UG Examiner, Manipal University, India and Annamalai University, India

B Viswanatha, MBBS, MS, DLO is a member of the following medical societies: Association of Otolaryngologists of India, Indian Medical Association, and Indian Society of Otology

Disclosure: Nothing to disclose.