Basal Ganglia Disorders Flashcards
Most common basal ganglia diseases:
Parkinson’s disease, Huntington Chorea and dystonias (including drug induced dyskinesias)
What do basal ganglia involve impairments in:
Muscle tone
Movement coordination and motor control
Postural stability
Presence of extraneous movement
What are dorsal or sensorimotor basal ganglia composed of:
Caudate nucleus
Putamen
Globus pallidus
What are the two brainstem nuclei involved?
Substantia nigra
Subthalmic nucleus
Relationship of the BG to Movement and Posture:
Automatic Movement Motor Problems Movement initiation and preparation Postural Adjustments Perceptual and Cognitive Functions
What do basal ganglia diseases result in?
difficulty initiating, continuing, or stopping movement
difficulty with muscle tone (particularly rigidity), and increased involuntary movements (tremor, chorea
Symptoms of basal ganglia disease:
Movement changes, such as involuntary or slowedmovements Increased muscle tone Muscle spasms and muscle rigidity Memory loss Problems finding words Tremor Uncontrollable, repeated movements, speech, or cries (tics) Walking difficulty
Parkinson’s Disease
Chronic progressive disease of the CNS with degeneration of dopaminergic substantia nigra neurons and nigrostriatal pathways
What does the loss of inhibitory dopamine result in?
excessive excitatory output from cholinergic system (acetycholine) of BG
Earliest signs of PD:
occur in the enteric nervous system
Medulla: particularly the olfactory bulb
NON-motor symptoms can precede motor symptoms
Classic symptoms of PD:
Rigidity (leadpipe or cogwheel)
Bradykinesia (hypokinesia)
Resting tremor
Impaired postural reflexes
When does resting temor appear?
Appears when muscles are relaxed: when hands are in lap or arms loosely held at the side
Where is resting tremor most common?
unilateral hand or foot
What exacerbates resting tremor?
stress or excitement
Rigidity:
Inflexibility & stiffness of limb, neck & trunk
Where is rigidity most common in PD?
neck, shoulder, and leg
Rigidity can lead to:
decreased ROM
decreased arm swing
pain/discomfort
Secondary Motor Symptoms:
Freezing Micrographia Mask-Like Expression Unwanted Accelerations Stooped posture Dystonia Swolling difficulty Slurred speech Soft speech
Pre-Diagnostic Signs of PD
Olfactory function PD patients prefer sweets! Autonomic function Incontinence, constipation, erectile dysfunction Sleep function REM sleep disorder Vivid dreams/acting out dreams Emotional/Cognition Depression, Apathy
Hoehn and Yahr 1:
unilateral involvement, usually with minimal or no functional disability
Hoehn and Yahr 2:
bilateral or midline involvement without impairment of balance
Hoehn and Yahr 3:
bilateral disease: mild to moderate disability with impaired postural reflexes; physically independent
Hoehn and Yahr 4:
severely disabling disease; still able to walk or stand unassisted
Hoehn and Yahr 5:
confinement to bed or wheelchair unless aided
Best prognosis in PD:
non-demented & tremor predominant cases of PD
Predictive factors for more rapid motor progression, nursing home placement, and shorter survival of PD:
Older age of onset Comorbidities Rigidity/bradykinesiaphenotype Decreased responsiveness to dopamine Dementia
Cognitive/Behavioral Status of PD:
Intellectual impairments/Dementia occurs in advanced stages
Memory
Bradyphrenia (slowing of thought processes)
Depression
Communication in PD:
Dysarthria Hypophonia (decreased volume) Mutism in advanced stages Mask like face with infrequent blinking and expression Writing becomes progressively smaller
Oromotor Control/Nutritional Status
Dysphagia
Problems in chewing and swallowing
Respiratory Status
Breathing patterns
Vital capacity
Decreased chest expansion
Where are common contractures in PD?
flexors, adductors
Persistent posturing in PD:
kyphosis with forward head
Many patients osteoporotic with high risk of fracture
Sensation/Perceptual Function in PD:
Aching and stiffness Abnormal sensations (cramp like sensations) Problems in spatial organization Perception of vertical Extreme restlessness (akathisia)
Vision in PD:
Blurring
Cogwheeling eye pursuit
Eye irritation from decreased blinking
Decreased pupillary reflexes
PD drugs to control tremor:
Anticholinergic drugs
PD drug to enhance dopamine release:
amantadine
What drug is used during early disease to slow progression:
selegiline
Diagnostic Categories of Atypical PD
Progressive SupranuclearPalsy
Cortical Basal Degeneration
Multiple System Atrophy
LewyBody Dementia
Clues Suggesting Atypical PD
Eye movement dysfunction Vertical saccade slowing Vertical gaze palsy: Downgaze > upgaze Upper motor neuron signs (DTR’s, Babinski) Cerebellar signs: dysmetria, ataxia Autonomic dysfunction Orthostatic hypotension Urinary incontinence Early onset/Rapid Progression Falls & dementia
Progressive Supramuclear Palsy:
Most common atypical parkinsonism
“tauopathy” due to accumulation of Tau protein in brain
Progressive Supramuclear Palsy signs:
Limited vertical eye movement: down > up Eye palsy= limited blinking Loss of righting reaction: fall backwards suddenly Severe axial rigidity “Surprised expression” Growling/groaning Increased extensor tone, wide BOS Dysphagia & dysarthria Cognitive dysfucntion& emotional lability
Which cranial nerve is tested in PSP?
CNIII
What area of brain is involved in multiple system atrophy?
alpha-synucleininclusions in the glial cells
cerebellar involvement
Mean onset of multiple system atrophy?
54 years of age
Multiple System Atrophy signs:
autonomic symptoms
Orthostatic hypotension, supine hypertension, urinary & sexual dysfunction, respiratory & breathing problems
▪**decrease >20 mm Hg systolic BP > 10 mm Hg diastolic
▪Impotence is often first symptom
▪Loud sighing
▪Gait & limb ataxia: irregular, jerky tremor,
▪Wide based gait vs. narrow in idiopathic
▪Head/oral dyskinesias
▪“Pisa” syndrome: frequent falls early
What is the second most frequent cause of dementia in elderly?
dementia with Lewy Body
Signs and symptoms of Lewy Body:
Rigidity, bradykinesia, tremor
Shuffling gait, instability, frequent falls
Depression, paranoid ideation
Hallucinations
Huntington’s Disease:
A fatal autosomal dominant hereditary disorder, which occurs with an insidious onset, generally occurring in the mid-30s – 40s
Signs and Symptoms of Huntington’s Disease:
Causes cognitive & emotional disturbances
Problems with voluntary a& involuntary movement
Degeneration of the caudate & putamen are most characteristic of HD.
Dystonia, Athetosis, akinesia, & bradykinesia develop
Other problems: executive function, STM, Visuospatial function (early) to dementia (late). Cause of death tends to be respiratory.
Stages I-III—MILD to Moderate of HD:
Increased concerns about cognitive issues
Irritability
Small coordination problems
Chorea: athetoid movements develop
Stage IV and V—Severe
of HD:
Lack of cognitive concern-dementia is late stages
Fatal stage-usually do to respiratory problems
