Approach to dysarthria or dysphagia: Clinical sciences

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Introduction0:00–0:25

Dysphagia, or impaired swallowing; and dysarthria, or impaired motor speech; are symptoms that can occur due to various neurologic- and non-neurologic conditions.
Some important neurologic causes include cranial nerve dysfunction, neuromuscular junction disorders, neurodegenerative conditions, demyelination, and stroke.
Now, if a patient presents with chief concerns suggestive of dysphagia or dysarthria, you should obtain a focused history and physical examination.

Dysphagia0:25–2:15

First, let's focus on dysphagia, which is difficulty swallowing. In this case, history might also reveal choking, coughing, or pain during swallowing.
On examination, you will also notice signs of impaired swallowing, such as difficulty clearing the mouth of food and water, and coughing with, or shortly after, swallowing.
These findings are suggestive of dysphagia, so your next step is to determine the type of dysphagia, more specifically, whether the patient is presenting with oropharyngeal or esophageal dysphagia.
But, before we proceed, let’s quickly review the mechanics of swallowing, which includes oral, pharyngeal, and esophageal phases.
The oral phase is voluntary and includes mastication, bolus preparation and moving the bolus into the pharynx. The pharyngeal phase consists of propelling the bolus through the pharynx and the upper esophageal sphincter.
During this phase, the epiglottis closes over the larynx to protect the airway. Finally, the esophageal phase includes peristalsis of the esophagus until the bolus passes through the lower esophageal sphincter into the stomach.
The oral cavity, pharynx, upper esophageal sphincter, and upper part of the esophagus have striated muscles innervated by cranial nerves, while the lower esophagus and lower esophageal sphincter have smooth muscles innervated by the esophageal myenteric plexus.

Oropharyngeal dysphagia2:15–3:06

Now, first, let’s focus on oropharyngeal dysphagia, which is associated with difficulty initiating swallowing and clearing food and liquids from the mouth.
Sometimes, your patient might also report drooling. If food or liquids end up in the airway, your patient might even experience choking and coughing.
Also, food and liquids might get out of the nose, known as nasal regurgitation. On the physical exam, you will see food or liquids left in the mouth after an attempt to swallow.
You might also visualize a structural abnormality in the mouth or pharynx, which can range from poor dentition to a mass lesion.
These findings suggest oropharyngeal dysphagia, so your next step is to assess the neurologic exam. If the neurologic exam is normal, consider structural oropharyngeal dysphagia, so be sure to obtain a nasal endoscopy to directly visualize the oropharynx and larynx.

Structural oropharyngeal dysphagia3:06–3:39

If the endoscopy reveals a structural abnormality, diagnose structural oropharyngeal dysphagia. Possible causes include changes from prior head and neck surgery, radiation therapy, malignancy, and Zenker diverticulum.

Propulsive oropharyngeal dysphagia3:39–4:38

On the other hand, if the neurologic exam reveals abnormalities, such as facial weakness, asymmetric palate elevation, tongue deviation, and signs of Parkinsonism, consider propulsive oropharyngeal dysphagia.
Next, obtain video fluoroscopy, which is also known as a modified barium swallow. This diagnostic method uses X-rays to evaluate swallowing mechanics after the patient ingests different consistencies of barium-containing fluids and solids.
If the video fluoroscopy reveals dysfunction without a structural lesion, possibly with signs of aspiration, diagnose propulsive oropharyngeal dysphagia.
However, keep in mind that propulsive oropharyngeal dysphagia can also occur due to non-neurologic causes, including connective tissue disorders and sarcoidosis.
Now, let’s go back and take a look at esophageal dysphagia, which is associated with the sensation of food and liquids getting stuck in the neck or chest.

Esophageal dysphagia4:38–5:51

The patient might also report chest pain or a medical history of gastroesophageal reflux disease, neck radiation, esophageal surgery, or medication-induced esophagitis.
In some cases, they might have a systemic medical condition, such as scleroderma, which can cause decreased or absent esophageal peristalsis; and immunosuppression, such as from HIV, which can result in infectious esophagitis.
On physical exam, you might find skin changes, such as from scleroderma or another mucocutaneous disorder. These findings should point you towards esophageal dysphagia, so, you need to obtain an esophagogastroduodenoscopy, or an EGD, to figure out the underlying cause.
Also, if you have concerns for esophageal motility conditions, be sure to obtain esophageal manometry. If the EGD shows an obstructing lesion or inflammatory changes, diagnose structural esophageal dysphagia.

Structural esophageal dysphagia5:51–6:09

This could be due to conditions like a Schatzki ring, peptic stricture, malignancy; or inflammation from medications and infections.

Propulsive esophageal dysphagia6:09–7:06

On the flip side, if there are no obstructing lesions or inflammatory changes on EGD, manometry shows abnormal esophageal pressures, diagnose propulsive esophageal dysphagia.
Most commonly, this could be from impaired peristalsis or dysfunction of the lower esophageal sphincter. In this case, you should think of achalasia, scleroderma, and esophageal spasms.
Now, here’s a clinical pearl to keep in mind! The patient’s history can give you clues as to whether they have structural or propulsive esophageal dysphagia.
Patients with structural esophageal dysphagia will typically report intermittent dysphagia to solids, while those with propulsive esophageal dysphagia will report persistent difficulties with both liquids and solids.

Dysarthria7:06–8:51

Now, switching gears and moving on to dysarthria, which is associated with changes in speech and difficulty speaking. On examination, you will notice impaired motor speech, including impaired articulation, phonation, or prosody.
Impaired articulation indicates issues with either lips, tongue, or throat. You can test this by asking the patient to repeat certain consonant sounds, such as “la-la-la-la", “me-me-me-me", or “kuh-kuh-kuh-kuh".
“M”, “B”, and “P” are labial consonants, “L” and “T” are lingual consonants, while “ng” and “nk” sounds are guttural articulations.
On the flip side, impaired phonation indicates an issue with the larynx or vocal cords and can be highlighted by asking the patient to repeat vowel sounds.
Keep in mind that the actual speech content, such as syntax and grammar, is normal. The patient also has normal written language and normal comprehension.
In some cases, you might find cranial nerve abnormalities, such as jaw deviation from trigeminal nerve dysfunction, facial weakness from facial nerve dysfunction, asymmetric palate elevation from glossopharyngeal or vagus nerve dysfunction, or tongue deviation from hypoglossal nerve dysfunction.
With these findings, diagnose dysarthria, so your next step is to determine the type, which can be hypokinetic, hyperkinetic, flaccid, spastic, and ataxic.
Hypokinetic dysarthria is characterized by monotonous, quiet, and slurred speech, which is often associated with muttering.

Hypokinetic dysarthria8:51–9:15

Occasionally, you will notice short rushes of speech. These findings are consistent with hypokinetic dysarthria, which is commonly seen with Parkinson disease and other causes of parkinsonism.
On the flip side, in hyperkinetic dysarthria, there’s variable volume and sound of speech with abrupt stops and starts. The voice tends to be harsh.

Hyperkinetic dysarthria9:15–9:49

Also, you will notice incoordination between speech and breathing. These findings are consistent with hyperkinetic dysarthria, which is often disturbed by abnormal hyperkinetic movements, such as chorea in Huntington disease or with myoclonus.
Hyperkinetic dysarthria can also be seen in Tourette syndrome. Next, in flaccid dysarthria, you will notice a breathy, hypernasal voice.

Flaccid dysarthria9:49–10:45

The physical exam also reveals a poor lip seal and difficulties with lingual articulations, such as “la-la-la" and “ta-ta-ta"; as well as labial articulations, such as “ma-ma-ma", and “ba-ba-ba".
Additionally, you might notice cranial nerve dysfunction such as jaw deviation, facial weakness, impaired palate elevation, absent gag and cough, and tongue deviation.
In some individuals, oral inspection might reveal tongue atrophy and fasciculations. These findings are consistent with flaccid dysarthria, which is associated with lower motor neuron injury, more specifically, lesions of cranial nerves involved in speech mechanics.

Spastic dysarthria10:45–11:27

Now, switching gears and moving on to spastic dysarthria. These patients will present with slow, strained, hypernasal, and harsh speech.
The exam might reveal facial weakness or tongue deviation, sometimes with increased jaw jerk. In contrast to flaccid dysarthria, there will be no tongue atrophy or fasciculations.
These findings are suggestive of spastic dysarthria, which is common in upper motor neuron injury and conditions like stroke, demyelination, and motor neuron disease, such as amyotrophic lateral sclerosis.
Finally, in ataxic dysarthria, the patient will present with scanning speech characterized by metronomic pauses after each syllable.

Ataxic dysarthria11:27–12:14

The speech is intermittently forceful, known as explosive speech. Also, articulation will be impaired.
With these findings, diagnose ataxic dysarthria, which is associated with conditions that affect the cerebellum, such as neurodegenerative conditions.
Now, here’s a clinical pearl to keep in mind! If there are no neurologic deficits on the exam, think of non-neurologic causes, like missing teeth, dry mouth, and even intoxication!
Alright, as a quick recap... Dysphagia, or impaired swallowing; and dysarthria, or impaired motor speech; are symptoms that can occur due to various neurologic- and non-neurologic conditions.

Review12:14–12:59

If you identify dysphagia, first, be sure to assess the type. In other words, be sure to determine if the patient is presenting with oropharyngeal or esophageal dysphagia, both of which can occur due to structural or propulsive conditions.
On the flip side, if you diagnose dysarthria, again, don't forget to determine the type, which can be hypokinetic, hyperkinetic, flaccid,
Approach to dysarthria or dysphagia: Video, Steps | Osmosis