SLHS 408 Neurogenic Swallowing Disorders

neurogenic swallowing disorders

occur when there is damage to the central or peripheral nervous system

isolation

some swallowing disorders occur in _____ while others are a symptom of a larger disease process

dysarthria

swallowing disorders are often classified within _____ categories: speech disorders attributed to a weakness, slowness, or incoordination

• cognitive

• oral

• pharyngeal/laryngeal

• esophageal

multiple systems are involved such as:

1. flaccid

2. spastic

3. ataxic

4. hypokinetic

5. hyperkinetic

what are the 5 major types of impairment

lower motor neuron damage

what is the etiology of flaccid dysarthria

• weakness (could also be paralysis)

• hypotonia

• diminished reflexes

• fatigue

what are the symptoms of flaccid dysarthria

• brainstem CVA

• muscular dystrophy

• ALS

• Myasthenia Gravis

• Guillain-Barre

what diseases may cause flaccid dysarthria

will depend on site of damage, but generally, weak muscle response can mean:

• poor chewing, movement of bolus (oral residue)

• weakness of velopharynx (nasal regurgitation)

• poor closure of larynx (aspiration)

• poor propulsion (squeezing) of the bolus downward (pharyngeal residue)

how does flaccid dysarthria impact the swallow

upper motor neuron damage

what is the etiology of spastic dysarthria

• weakness

• loss of fine, skilled movements

• increased tone

• increased reflexes

• spasticity

what are the symptoms of spastic dysarthria

• CVA

• anoxic brain injury (ex. cerebral palsy)

what diseases may cause spastic dysarthria

will depend on site of damage, but generally the hypertonicity, weakness, and spasticity will cause:

• poor chewing, movement of bolus (oral residue)

• poor timing and coordination of specific movements that initiate swallow

• poor closure of larynx (aspiration)

• weakness/improper movement of velopharynx (nasal regurgitation)

• poor propulsion (squeezing) of the bolus downward and now may have spasms in the esophagus

how does spastic dysarthria impact the swallow

cerebellar damage

what is the etiology of ataxic dysarthria

• slowness and inaccuracy of movement

• difficulty with coordination of movement

• tremor

what are the symptoms of ataxic dysarthria

• degenerative diseases

• CVA

• tumors

what diseases may cause ataxic dysarthria

• biting tongue/cheek when eating

• poor respiratory coordination during swallowing (can lead to aspiration)

how does ataxic dysarthria impact the swallow

basal ganglia dysfunction

what is the etiology of hypokinetic dysarthria

• slowness of movements

• diminished movements

• sensory impairments

• rigidity

• tremors

what are the symptoms of hypokinetic dysarthria

Parkinson’s Disease

what diseases may cause hypokinetic dysarthria

• drooling

• tremor of oral musculature impacts oral prep and transit phase

• decreased frequency of swallow (aspiration)

• decreased movement of structures that close the larynx and protect the airway (aspiration)

how does hypokinetic dysarthria impact the swallow

basal ganglia dysfunction

what is the etiology of hyperkinetic dysarthria

• abnormal, rhythmic movements

• irregular and unpredictable movements

• slow, involuntary movements

what are the symptoms of hyperkinetic dysarthria

Huntington’s Disease

what diseases may cause hyperkinetic dysarthria

• motor control across all phases of the swallow are affected—any number of impairments can be seen

how does hyperkinetic dysarthria impact the swallow

mixed impairments

any combination of two or more of the single impairment types is possible; neurologic disease is distributed across two or more dimensions of the nervous system; one type may predominate

combined neurologic events

• multiple CVAs

• PD + CVA

• advancement of degenerative neurologic disease (ALS, MS)

what causes a mixed impairment

Amyotrophic Lateral Sclerosis (ALS or Lou Gehrig’s disease)

• half of the motor neurons have already died before symptoms even appear

• etiology (unknown)

  • 5-10% have familial type

  • protein aggregation

    • TDP-43

• LMN: fasciculations, muscle atrophy, weakness

• UMN: spasticity, hyperreflexia, emotional lability

what are the signs of ALS