Differential Diagnosis Flashcards
Differential diagnosis –
the process of narrowing possibilities and reaching conclusions about the nature of a deficit.
When doing a speech evaluation, should you always try to make a diagnosis?
Yes
Reasons for not being able to make a diagnosis include (2):
o Noncooperative patient
o Equivocal/uncertain findings
Why is it helpful to state what it is not in a diagnosis?
– i.e. if it is not ataxic – implies that there isn’t cerebellar involvement
- if it is not hypokinetic or hyperkinetic – there is no basal ganglia involvement
*can state these things
Is it helpful to establish that a dysarthria is present but that can’t specify the type?
Yes, if you cannot give a definitive diagnosis
If you can’t make a definitive diagnosis what should you do?
You must describe what you find, and state why a definitive diagnosis can’t be made
If a diagnosis is not determined should you offer a diagnosis?
No
You can state that the diagnosis is undetermined. Also using words such as “equivocal, probably, possible” give indications of how confident you are in your diagnosis
Make the speech diagnosis relate to:
- the suspected neurological diagnosis
- or suspected site of lesion
*It is helpful to the neurologist if the speech signs are not consistent with suspected diagnosis or site of lesion as well as when they are consistent with suspected diagnosis
Is it possible for more than one speech disorder to exist at the same time?
Yes,
*so just identifying a single disorder isn’t always sufficient.
- You must be able to account for all of the deviant characteristics – if the disorder you identified does not do this, then another disorder may be present
Does an evaluation always have to find deviant speech?
No.
it may indicate normal speech or speech within normal range
By providing a label for the diagnosis, you are providing:
a composite of information associated with that label
It is a kind of shorthand for communicating information about disorders
Is there is overlap among dysarthrias in terms of certain characteristics?
Yes
For example, many have imprecise articulation as a characteristic, so the presence of imprecise articulation DOESN’T HELP you in distinguishing between dysarthrias.
Are there also some characteristics that are unique to certain dysarthrias?
Yes
and these CAN be used to distinguish between dysarthrias.
Why might an evaluation come up with speech WNL but the patient still has a disorder (2)?
In the initial stages of some diseases, speech may have changed but not significantly enough to be judged deviant
It is also possible that the person may be incorrectly identifying a developmental problem of articulation as related to a neurological disease.
Etiologies (10):
1 Vascular
2 Degenerative disease
3 TBI
4 Surgical trauma
5 Toxic and metabolic conditions
6 Infectious and inflammatory conditions rarely cause dysarthrias
7 Demyelinating diseases
8 Anatomic malformations such as Arnold-Chiari (malformations of the brain)
9 Neuromotor junction disorders, muscle disease and neuropathies
10 OR in the absence of a neurologic diagnosis
Vascular –
can cause any type of dysarthria
Most often it causes spastic, UUMN, and ataxic dysarthia.
Hemorrhagic stroke is the most common cause of dysarthrias
Degenerative disease -
- also can cause any type of dysarthria
- Most often it causes spastic, ataxic, hypokinetic and flaccid dysarthrias
- ALS is a frequent cause of flaccid & spastic but other types of dysarthrias are not usually seen in ALS, so if there is another type of dysarthia existing, there may be another disease or the diagnosis of ALS may be in error.
- Also Parkinson’s is only associated with hypokinetic dysarthria
TBI –
- can cause any type of dysarthria
- but in closed head injury the most common type is spastic
- OHI do not usually cause flaccid dysarthria but can cause the other CNS dysarthrias (spastic, ataxic, UUMN).
- Skull fracture and neck traumas can cause flaccid dysarthrias, but not other types
Surgical trauma –
- can cause any type of dysarthia except hypokinetic.
- Surgeries involved with ear, nose throat, chest/cardiac areas are only associated with flaccid dysarthria.
- Neurosurgery can cause CNS dysarthrias as well as flaccid dyarthria
Toxic and metabolic conditions –
- do not typically cause flaccid or UUMN dysarthria but can cause the other types
- Toxic conditions associated with drugs/medications cause hyperkinetic and ataxic dysarthias most often
Infectious and inflammatory conditions -
- rarely cause dysarthrias although they sometimes do occur
- The type of dysarthria depends on the condition
Demyelinating diseases –
- can cause any type of dysarthria but hypokinetic is rare.
- The type of dysarthria depends on the disorder, Guillain Barre disease is usually associated with flaccid whereas
- MS is usually associated with ataxic dysarthria
Anatomic malformations -
-e.g. Arnold-Chiari (malformations of the brain)
– most often associated with flaccid dysarthria
Neuromotor junction disorders, muscle disease and neuropathies –
- only cause flaccid dysarthria because they are PNS diseases
Dysarthria present in the absence of a neurologic diagnosis -
- sometimes the etiology is undetermined particularly for hyperkinetic, spastic and ataxic dysarthrias
Oral Mechanism Findings are used for:
– certain findings in the oral mechanism are not required for MSD but are used as confirmatory signs:
Oral Mechanism Findings for Flaccid Dysarthria:
– atrophy and fasiculations often occur in FD and do not occur in other dysarthias or apraxia
- Hypotonia and a hypoactive gag reflex occur more often in FD than other dysarthrias
- Rapid loss of intelligibility is indicative of Myasthenia Gravis but not other MSDs
- Nasal regurgitation may be seen FD
Oral Mechanism Findings for Spastic Dysarthria:
- pathological oral reflexes
- hyperactive gag reflex
- and pseudobulbar effect are found most often in this dysarthria
- Also more problems exist with dysphagia and drooling than other MSDs but may occur with others
Oral Mechanism Findings for Ataxic Dysarthria:
– may have dysmetria in nonspeech jaw, face and tongue movements
(This isn’t seen in other dysarthrias typically)
- Other oral mech findings may be normal
Oral Mechanism Findings for Hypokinetic Dysarthria:
– orofacial tremors
- masked face is common and not seen with other MSDs
Oral Mechanism Findings for Hyperkinetic Dysarthria:
- abnormal movements may be seen both at rest and in speech that are not seen in other dysarthrias
Oral Mechanism Findings for UUMN Dysarthria:
- unilateral facial and lingual weakness without atrophy or fasiculations is common but not typically seen in other dysarthrias
Speech Characteristics of Flaccid Dysarthria:
– phonatory and resonatory abnormalities are most common distinguishing characteristics.
- If the Xth nerve is affected you may see breathiness, diplophonia, audible inspiration & short phrases – these are not as common in other dysarthrias
- Breathiness does occur in hypokinetic dysarthria but listen for greater hoarseness and the presence of diplophonia in FD which would differentiate the two.
- Hypernasality occurs in other dysarthrias, most often spastic and hypokinetic, but still is most pronounced in FD.
- Rapid deterioration of speech occurs only in connection with FD in Myasthenia Gravis
Speech Characteristics of Spastic Dysarthria:
– slow rate combined with slow but regular AMRs, strained voice quality are most common features and aren’t typically seen in other dysarthrias
- It is the presence of all three that is not typical in other dysarthrias.
- You may have a strained voice quality in hyperkinetic dysarthria but it usually isn’t accompanied by the slow rate
Speech Characteristics of Ataxic Dysarthria:
- irregular articulatory breakdowns, irregular AMRs and dysprosody are primary distinguishing characteristics.
- You may also hear these in UUMN and hyperkinetic dysarthria but to distinguish look for abnormal movements in hyperkinetic dysarthria and unilateral lower facial and tongue weakness in UUMN
Speech Characteristics of Hypokinetic Dysarthria:
- the only dysarthria in which rapid and blurred speech and AMRs occur but it doesn’t have to occur in hypokinetic dysarthria
- If palilalia occurs – it only occurs with hypokinetic dysarthria
Speech Characteristics of Hyperkinetic Dysarthria:
- abnormal movements are particular to this dysarthria
Speech Characteristics of UUMN Dysarthria:
- its mildness and transient duration helps to differentiate UUMN
- It may be confused with ataxic due to irregular breakdowns
- AMRs are usually normal but can be mildly irregular.
- The voice may sound somewhat spastic because of strained voice, but is usually milder in degree than Spastic Dysarthria
- It rarely has hypernasality
Dysarthria versus Apraxia:
• Apraxia occurs with what kind of damage? (2 things)
- left hemisphere lesions except when there is right hemisphere language dominance or mixed dominance
- supratentorial damage
Dysarthria versus Apraxia:
• Dysarthria occurs with damage to:
supratentorial, posterior fossa, spinal or peripheral lesions
Dysarthria vs. Apraxia:
• Apraxia occurs primarily with lesions to what system(s)?
the carotid system
Dysarthria vs. Apraxia:
• Dysarthria occurs with damage to what system(s):
not only with carotid lesions but with other vascular systems lesions
Which dysarthria is most difficult to differentiate from AOS?
UUMN
Speech Characteristics that differentiate AOS and dysarthria:
Oral mech exams indicate the neuromuscular problem associated with…
dysarthria
Speech Characteristics that differentiate AOS and dysarthria:
Which subsystems are affected with dysarthria?
– all subsystems affected
Speech Characteristics that differentiate AOS and dysarthria:
Which subsystems are affected with Apraxia of Speech?
– mainly articulation and prosody are affected
Speech Characteristics that differentiate AOS and dysarthria:
Which is more often associated with aphasia?
- AOS is more often associated with aphasia than dysarthria
Speech Characteristics that differentiate AOS and dysarthria:
What kinds of articulation errors do we see with AOS and dysarthria?
o Artic errors are usually distortions in dysarthria & in apraxia
(Recent research indicates errors are mostly distortions in apraxia and are predictable – not substitutions as once thought.)
Speech Characteristics that differentiate AOS and dysarthria:
Which do you see groping behaviors?
o Apraxic speakers grope, dysarthria speakers do not.
Patients with phonemic paraphasias may also present with groping behaviors.
Dysarthria vs Aphasia:
Oral Mech Exam
o Aphasia patients can have normal oral mech exam, dysarthria usually do not
Dysarthria vs Aphasia:
Language problems
• Dysarthria patients do not have language problems, aphasia patients do
Forms of Neurogenic Mutism(5):
table 15-6, page 368
1 Conditions that have diffuse or multifocal damage 2 Anarthria – (lack of speech) 3 Mutism related to apraxia 4 Mutism due to aphasia 5 Cognitive-affective disturbances
Neurogenic Mutism:
1 Conditions that have diffuse or multifocal damage:
are more likely to be associated with mutism due to cognitive-affective disturbances than with anarthria, AOS,aphasia
Neurogenic Mutism:
2 Anarthria – (lack of speech)
– usually have significant neuromotor deficits in bulbar muscles that cause mutism
- It’s sometimes present without limb motor deficits.
- Usually has significant dysphagia and other oromotor abnormalities and this helps in dx
- Rarely does anarthric mutism occur in absence of nonspeech oromotor abnormalities
- When attempting to speak, their restricted articulatory ROM, reduced loudness and strained, groaning quality is diagnostic
Neurogenic Mutism:
3 Mutism related to apraxia
- can be associated with normal findings in oral mech exam
- Mute apraxic pts usually try to speak and show frustration when they can’t
Neurogenic Mutism:
4 Mutism due to aphasia
- similar to mute apraxic pts except they may have problems following instructions
- If mutism is present, aphasia is usually severe so they do poorly on language tests
Neurogenic Mutism:
5 Cognitive-affective disturbances
– May be due to reduced arousal and alertness
- If speech does eventually occur, there are delays with brief unelaborated speech
