Overview
Various causes of impaired or loss of articulation commonly have difficulty in articulation, lack of clarity, and in severe cases, complete loss of speech The main causes include stroke, brain tumor, cerebral palsy, Parkinson’s disease, amyotrophic lateral sclerosis, myasthenia gravis, etc. The main focus is on rehabilitative treatment, and the primary cause is actively treated.
Definition
Dysarthria is a speech disorder in which abnormal articulation occurs as a result of dysfunction or disease of the nervous system, muscles, or organs of articulation.
It is often characterized by abnormal control of articulation, unclear biting of words, abnormal volume, pitch, speed and rhythm, excessive nasal sound and other changes, and in severe cases, others can not understand or can not speak at all [1-2].
Classification
Classification is mainly based on the cause of the disease [1-4].
Motor dysarthria: so-called narrow dysarthria, including spasmodic, flaccid, dysarthric, hyperkinetic, hypokinetic and mixed types.
Organic dysarthria: caused by abnormalities in the morphology of the oral cavity, pharynx and other organs of sound production, typically represented by cleft palate, but also commonly found in cleft lip and palate, facial clefts, megakaryotympanic syndrome, dental occlusion abnormalities, congenital palatopharyngeal insufficiency, and so on.
Functional dysarthria: there is no morphological or functional abnormality in the organs of sound formation, and hearing is normal. The cause is not clear, but it may be related to the reception of speech information, discrimination, and emotion.
Morbidity
Dysarthria is one of the common complications following neurological lesions such as stroke and Parkinson’s disease.
Motor dysarthria is the most common type.
The incidence of motor dysarthria in stroke and craniocerebral injury patients in China is 20%-30% and 10%-60%, respectively [1-2].
Etiology
Causes
The following etiologic factors can directly or indirectly damage the nerves and muscles associated with articulation, resulting in dysarthria [3-5].
Cerebrovascular diseases, such as cerebral infarction, cerebral hemorrhage, and subarachnoid hemorrhage.
Traumatic brain injury: such as cerebral contusion, traumatic intracranial hemorrhage, diffuse axonal injury, etc.
Brain occupying disease: such as brain tumor, brain metastasis, brain abscess, etc.
Intracranial infection, inflammation: such as bacterial encephalitis, viral encephalitis, autoimmune encephalitis, etc.
Neurodegenerative diseases: such as multiple sclerosis, Alzheimer’s disease, amyotrophic lateral sclerosis, progressive supranuclear palsy, cerebellar degenerative diseases, etc.
Metabolic and toxic encephalopathy: such as hepatic encephalopathy, pulmonary encephalopathy, chronic alcoholism, carbon monoxide poisoning delayed encephalopathy.
Basal nucleus lesions: such as Parkinson’s disease, hepatomegaly, etc.
Cranial nerve or peripheral neuropathy lesions: such as progressive medullary palsy, acute myelitis, Guillain-Barré syndrome, brainstem tumors, medullary cavernous, paraneoplastic syndromes, motor neuron disease, and cranial base damage caused by various reasons.
Muscle pathology: e.g. myasthenia gravis, progressive muscular dystrophy and ankylosing myopathy.
Pathogenesis
Dysarthria is primarily concerned with the articulatory process.
It may be due to incorrect motor commands from the brain to the muscles that govern the organ of articulation.
Or, although the motor commands given are correct, they cannot be executed accurately due to abnormalities in the structure, strength, and muscle tone of the organ of articulation itself.
Problems with any of the above can affect the clarity, fluency, etc. of speech.
Symptoms
Main Symptoms
Patients with dysarthria may have abnormalities in word biting, volume, pitch, speech rate, rhythm, and nasality.
Multiple types of problems often occur at the same time, and in severe cases, the ability to speak or pronounce words can be completely lost. Taking the most common motor dysarthria as an example, the common manifestations are as follows [5-8]:
Spasmodic dysarthria: It is characterized by effortful speech, rough, runny tone, dragging rhythm, sharp changes in volume and pitch, with unnatural interruptions, and excessive nasality.
Flaccid dysarthria: It is characterized by unstable breath, inappropriate pauses, inability to pronounce consonants such as “b, p, f”, and weak nasal sounds.
Dysarthric dysarthria: mainly characterized by dysrhythmia, rhythmic dysarthria, labored articulation, loud sounds, misplaced stress, abnormal intonation, and unstable rhythm.
Excessive movement dysarthria: excessive changes in articulation, too “staccato”. Sharp changes in voice strength, excessive nasalization, distortion of vowels and consonants, lack of stress, inappropriate pauses.
Hyperkinetic dysarthria: The symptoms of dysarthria are volume, monotone, reduced stress, “flatness”, breathy sounds, or loss of voice.
Mixed dysarthria: a combination of the above symptoms.
Consultation
Department of Medicine
Neurology
When dysarthria or slurred speech occurs, it is advisable to consult a doctor to determine the cause of the problem.
Neurosurgery
Neurosurgery is necessary in cases of traumatic brain injury, intracranial space occupation, and dysarthria due to various reasons.
Otorhinolaryngology and Stomatology
In case of trauma to the throat, tumor, cleft lip and palate, etc., it is necessary to consult ENT and stomatology.
Rehabilitation
After the cause of the disease is clear and the condition is stabilized, rehabilitation treatment should be carried out in time, and the treatment process is mainly carried out in the Department of Rehabilitation.
Preparation for medical treatment
Consultation: registration, preparation of information, common questions
Tips for medical treatment
Patients have difficulty in communicating with the doctor and need to write or be accompanied by their family members.
Try to record the manifestations and characteristics that have appeared, in order to give the doctor more reference.
Preparation List
Symptom list
Pay special attention to the time of onset of symptoms, special manifestations, etc.
Is there intermittent, short, incomplete speech?
Is there any difficulty in articulation, slurred speech?
Is there any abnormality in vocalization, intonation or speed of speech?
Is there a complete inability to pronounce words?
List of medical history
Is there any cerebrovascular disease, traumatic brain injury, or brain occupying disease?
Is there any intracranial infection, inflammation, neurodegenerative disease, metabolic or toxic encephalopathy?
Are there cranial nerve or peripheral neuropathy lesions?
Any generalized or pharyngeal muscular or structural lesions?
What previous treatments have been received?
Checklist
Test results from the last six months, which can be brought with you to the doctor’s office
Laboratory tests: blood glucose, liver function, kidney function, blood routine, rheumatologic and immune indicators, tumor markers, infections, etc.
Instrumental examination: ① Nasal flow meter examination; ② Laryngeal aerodynamic examination; ③ Fiberoptic laryngoscopy, electronic laryngoscopy; ④ Electroacoustic portography; ⑤ Electromyography; ⑥ Computerized voice analysis system.
Imaging examination: cranial CT, cranial MRI, etc.
List of medications used
Medication used in the last 3 months, if there is a medicine box or package, you can bring it to the doctor
Cerebrovascular disease preventive medication: aspirin, clopidogrel, atorvastatin, etc.
Diagnosis
Diagnosis based on
Medical history
With cerebrovascular disease, traumatic brain injury, brain occupying disease.
With intracranial infection, inflammation, neurodegenerative disease, metabolic or toxic encephalopathy.
Have cranial nerve or peripheral neuropathy lesions.
Have generalized or pharyngeal muscular or structural lesions.
Clinical manifestations
Symptoms
Difficulty in articulation, dysarthria, abnormalities in vocalization, intonation and speech rate, and in severe cases, complete loss of oral expression or articulation.
Physical examination
Doctors often conduct examinations of the gag reflex, palpebral reflex, and the appearance and movement of the oropharynx.
Gag reflex: Whether there is a noticeable feeling of nausea and dry heaving when the back wall of the throat is pressed with a tongue depressor.
Palm-jaw reflex: Whether the contraction of the ipsilateral mandibular muscles is induced by scratching the skin of the palms of the hands with a blunt needle or pricking the skin of the palms of the palms of the hands at the level of the pisiform region.
Oropharyngeal clinical examination: listen to the patient’s voice characteristics when speaking, observe the patient’s face, such as lips, tongue, jaw, palate, pharynx and throat movement in quiet and speaking, respiratory status, let the patient do all kinds of oropharyngeal movements, pronunciation to determine whether there is any abnormality.
Laboratory examination
Purpose of examination: to understand the systemic status, such as whether there are infections, inflammation, poisoning, metabolic abnormalities, autoimmune diseases, and so on.
Common items: including routine blood test, blood sugar, blood lipid, immune index, antibody, tumor marker test, etc.
Precautions: Fasting is required, and multiple follow-ups may be required during the course of treatment.
Cranial Magnetic Resonance Imaging (MRI) Examination
Purpose of examination: To detect structural abnormalities or lesions in the brain, which can help to clarify the cause of the disease and determine the location and nature of the lesion.
Common findings: Different lesions such as intracranial hemorrhage, occupancy, infarction, edema and degeneration can be detected.
Precautions: Those who have dentures or metal implants in the body, such as cardiac stents, etc., need to inform the doctor, who will decide whether the MRI examination can be performed.
Dysarthria examination
Purpose of examination: To diagnose the type and severity of dysarthria qualitatively and quantitatively, to formulate a rehabilitation program, and to evaluate the efficacy of treatment.
Scale examination: China Rehabilitation Research Center dysarthria examination method, modified Frenchay dysarthria evaluation method, etc.
Instrumental examination: Nasal flow meter examination, laryngeal aerodynamic examination, fiberoptic laryngoscopy, electronic laryngoscopy, electroacoustic tomography, electromyography, computerized voice analysis system, etc.
Common findings
Abnormal oropharyngeal muscle movement, including speed, rhythm, range, etc.
Abnormal pitch and volume of speech, including breath sound, rough sound, nasalization, speech tremor, poor clarity and comprehensibility of conversation.
Accompanied by difficulty in swallowing, increased salivation, poor respiration and other manifestations.
Cautions: Evaluation should be deferred for those with poor general condition, progressive stage of illness, impaired consciousness, and inability to cooperate with the examination.
Differential Diagnosis
Aphasia
Similarities: Both have poor speech.
Differences: Aphasia is characterized by inability to speak, understand, understand words, recognize words, and write. Dysarthria only involves the function of “speaking”.
Aphasia
Similarities: The clinical manifestations of aphasia are the inability to pronounce words.
Difference: aphonia is a complete loss of voice caused by bilateral vocal cord paralysis, only whispering but no speech, the vocal cords can not be separated during inhalation and inspiratory stridor may occur, laryngoscopy can be used to make a differential diagnosis.
Mutism
Similarities: Both can be characterized by the absence of speech.
Differences: Mutism is a psycho-emotional abnormality, but there is no abnormality in the phonological function of speech, and there is no abnormality in the neuroimaging and muscle examination related to voice formation.
Treatment
Treatment objective: actively treat the primary disease, improve and compensate for the function of phonation, and improve the quality of life.
Treatment principle: Rehabilitation is the main treatment, with drugs, surgery, non-invasive neurological intervention technology and other methods [7-10].
Rehabilitation treatment
Training for the articulatory function
Usually includes relaxation training, breathing training, sound-constituting movement training, voice training and other training methods.
Treatment is generally based on gradual improvement of respiration, resonance, vocalization, phonation, and phonological cues.
Relaxation training
It is mainly applicable to patients with spasmodic dysarthria.
It reduces the tension of articulatory muscles by relaxing the shoulder and neck muscles.
Breathing
Adjusting breathing helps to improve breath, volume and rhythm.
Breathing can be done calmly in different positions such as supine, sitting, standing, etc.
Jaw, tongue and lip training
The patient’s jaw and temporomandibular joints can be gently tapped to induce mouth closure and prevent the jaw from extending forward.
Train the lip movements such as opening and closing the mouth, pouting and pursing the lips.
Train the anterior extension, posterior retraction, upward and lateral movement of the tongue and the strength of the tongue muscles.
Speech training
Tell the patient the correct position of the tongue, lips and teeth, the direction and size of the airflow, and correct the wrong movements of the mouth and face through mirrors, photographs and mouth charts.
Imitate the therapist’s pronunciation, including individual vowels and consonants, combined consonants, rhymes, and tetragrammaton, and gradually transition to single words, phrases, and sentences after mastery.
Speaking Speed Training
Utilizing a metronome to control the speed of speaking, starting slowly and gradually becoming faster, while ensuring clarity of pronunciation.
Tone Recognition Training
By listening to others or playing recordings, the patient can distinguish the wrong sounds and increase sensitivity to mispronunciation.
This can be done in the form of group training, where the patient speaks a passage and other patients comment on it, and the therapist corrects it at the end.
Training to overcome nasalization
The patient can be guided to control the oral airflow by blowing candles, trumpets and whistles.
Palate muscle training: let the patient use both hands to push or support the desktop, and at the same time pronounce the “ah” sound, in order to promote the palate muscle contraction and uplift; pronounce the “kah” sound, which can also be used to strengthen the soft palate muscle to promote the palatopharyngeal closure.
Rhythmic training
The patient can be accompanied by musical instruments to practice changes in pitch, volume and rhythm.
Syllable folding training
Suitable for spasticity, dyskinesia, delayed dysarthria.
Allow the patient to flex one finger for each sound, with the speed of the sound being the same as the speed of the flexed finger, so that the patient can improve his/her speech, achieve autonomous control of speech, and improve the clarity of speech.
Non-verbal communication
When the dysarthria still cannot be effectively improved or communicated after systematic training, the use of non-verbal communication modes such as sign language, drawing, communication boards or communication manuals should be considered as a substitute.
Electronic devices such as electronic articulators, computerized text readers, and environmental control systems are also available.
Training precautions
The treatment environment should be as quiet as possible, avoiding noise, so as not to disturb the patient’s mood, aggravate tension and distraction.
Health education for the patient’s family is needed during the training process so that the family can assist the patient in completing the treatment tasks outside the hospital and record the completion of the tasks to ensure the continuity of the treatment.
Etiologic treatment
According to the cause of dysarthria, etiologic treatment should be actively carried out, and the following are only some examples [9-14].
Patients with cerebral infarction: thrombolytic treatment with alteplase is often used in the acute stage, and aspirin, clopidogrel, atorvastatin and other drugs are often used in the recovery stage, and hyperbaric oxygen is used.
Parkinson’s disease patients: often use levodopa, pramipexole and other drugs, but also can use deep brain electrical stimulation treatment.
Multiple sclerosis patients: often use methylprednisolone, immunoglobulin, plasma replacement and other treatments.
Patients with hepatomegaly: D-penicillamine, triethyltetramine, sodium dimercaptosuccinic acid and other drugs can be used to dispel copper treatment.
Other treatments
Surgical treatment: patients with organic dysarthria such as cleft palate, cleft lip and palate, facial cleft, and megaglossia can be treated surgically according to the type and degree of the lesion.
Non-invasive neuromodulation technology: For dysarthria caused by brain injury, repetitive transcranial stimulation (rTMS) and transcranial direct current stimulation (tDCS) can be used to promote the improvement of neural function. However, it is not suitable for patients with metal objects in the skull, large cranial defects, and epilepsy.
Electrical stimulation treatment: most of the oropharyngeal muscles are involved in swallowing movement at the same time, so the swallowing function electrical stimulator can be used to assist the treatment.
Prognosis
Cure
Most patients with dysarthria due to brain lesions show the most significant functional improvement within 6 months after onset of the disease, with less improvement occurring between 6 and 12 months, and difficult to improve beyond 1 year.
Patients with organic dysarthria are difficult to improve if the primary pathology is not effectively treated.
Patients with functional dysarthria have a relatively good prognosis if diagnosed and treated in a timely manner.
Prognostic factors
There are many factors that affect the prognosis of dysarthria, and the following factors are not favorable for recovery:
Advanced age.
Large brain lesions or involvement.
Concomitant depression, psychiatric disorders, cognitive decline, inability to cooperate with treatment, or alcohol, drug, or other substance abuse.
Inadequate or ineffective treatment in the acute phase, continued progression of the disease, and failure to standardize rehabilitation.
Harmful
Dysarthria can reduce the patient’s speech and social communication ability, seriously affecting the patient’s daily life, employment, participation in social activities, and aggravating the burden on the family and society.
The treatment cycle of dysarthria is long and slow, and patients are prone to anxiety, low self-esteem, depression and other psychological problems.
Daily
Daily Management
Dietary management
Diet should be adjusted according to the primary cause of the disease, and attention should be paid to balanced nutrition.
Dysarthria is common in stroke patients, so low-salt and low-fat diet should be paid attention to.
Patients with dysarthria are often associated with swallowing problems and should be fed mainly with paste or thick food, if necessary through a nasal feeding tube.
Life management
Regular work and rest, ensure sufficient sleep time, do not smoke, do not drink alcohol.
Create a quiet and comfortable living environment and avoid exposing the patient to excessive stimuli, such as noise and crowds of people.
Use gestures, writing, computerized text readers, etc. to assist communication.
Psychological support
Maintain optimism in daily life, family members care more about the patient, increase communication and exchange with the patient.
Patients themselves try to minimize anxiety, maintain a stable, positive and optimistic mental state, and establish confidence in overcoming the disease, which will help in the recovery of the disease.
If necessary, professional psychological practitioners can be sought.
Disease monitoring
Pay attention to and record changes in voice function, such as fluency, clarity and volume of speech.
Control the underlying disease, such as cerebrovascular disease patients to monitor blood pressure, blood sugar, weight and other indicators.
Follow-up
Follow-up time: It is usually recommended to review once every 1 to 2 months, and once every 3 to 6 months after the condition is stabilized.
Review items: cranial magnetic resonance, organ function test, etc.
Prevention
Dysarthria is mainly prevented by avoiding and controlling the primary disease:
Low-salt and low-fat diet, balanced nutrition, and ensure the intake of vegetables and fruits.
Participate in appropriate physical exercise and avoid strenuous exercise.
Manage blood pressure, blood sugar, blood fat, etc., and quit smoking and drinking.
Avoid traumatic brain injury, poisoning, infection and other diseases.