Multimedia Encyclopedia
Delayed swallow reflex
Refers to when a person’s automatic swallow reflex—which normally kicks in when liquid or chewed food in the mouth reaches the base of the tongue—is delayed. Individuals with normal swallowing rarely notice or think about the action of their swallow reflex, but on occasion the reflex may startle a person and draw more attention to itself: for example, when a person sucks on a hard candy that inadvertently goes a little too far back in the mouth and—gulp!—it is involuntarily swallowed.
If a person’s swallow reflex is delayed, then food material may slip back to the base of the tongue and, before the swallow happens, drop down to fill the vallecula or even the pyriform sinuses. A delayed swallow reflex is of particular concern when swallowing liquids because, given their low viscosity, thin liquids can easily flow downward into the larynx and trachea (aspiration). Compare this disorder with absent swallow reflex.
Di-indolemethane (DIM)
Di-indolemethane (DIM) is a phytochemical derived from cruciferous vegetables such as cabbage, broccoli, Brussels sprouts, cauliflower, collards, and kale. Promotes estrogen metabolism to a form that has been shown to be anti-proliferative. Used in treating recurrent respiratory papillomatosis (RRP). See also: indole-3-carbinol (I3C).
Diagnostic model
Diagnostic model refers to the codified tools and sequence used during diagnosis of a disorder. In the realm of voice disorders in particular, different clinics may use different models for diagnosis. For purposes of discussion, at our practice we distinguish somewhat artificially between the traditional diagnostic model, the technology-driven or reductionistic diagnostic model, and what we prefer: the integrative diagnostic model.
Diet modification for dysphagia
Diet modifications for dysphagia are suggested dietary changes, particularly regarding food consistencies, directed at improving a patient’s ability to swallow and at avoiding aspiration. For example, an individual who is struggling with aspiration might be advised to avoid thin liquids and use thicker or carbonated liquids instead. Or this individual might be advised to avoid composite foods, since his or her swallowing deficiency could make it harder to “stay organized” with several consistencies in the mouth at once.
Differential diagnosis
Differential diagnosis refers to the short list of possible diagnoses based upon the findings of the initial consultation. Sometimes the diagnosis can be narrowed down to only one possibility; in other cases, additional tests are done to distinguish between competing diagnoses. Sometimes the most likely diagnosis of those in the differential diagnosis becomes the working diagnosis and trial treatment for this leading diagnosis is begun.
Dilatation (Dilation)
Dilatation, or dilation, is to stretch an opening to a larger size. When an individual has stenosis of the laryngeal airway or the trachea, a dilation procedure is one option for treatment. The two primary methods of dilation in these cases are to use either a balloon expansion device or successively larger tapered laryngeal dilators. With tracheal stenosis, a balloon expansion device might be used more often, but for high tracheal stenosis, the tapered laryngeal dilators can also be very effective.
Photos of Dilatation:
Subglottic stenosis, before dilation (1 of 2)
This individual has undergone at least a dozen prior dilations, each of which provides dramatic relief from noisy breathing and exercise intolerance. Here the patient is halfway to needing re-dilation, due to the typical inflammatory stenosis that is seen. Compare with photo 2.
Subglottic stenosis, after dilation (2 of 2)
One week after one of this patient's dilations (with Kenalog injection and topical Mitomycin C), showing a dramatic widening of her airway; compare with photo 1. After a number of years, inflammatory lesions such as this sometimes "burn out," and the interval between dilations increases.
Subglottic stenosis (1 of 5)
Middle-aged woman with unexplained shortness of breath and noisy breathing, due to this idiopathic inflammatory and very high subglottic stenosis. The patient initially declined dilation due to her anxiety. She also had granularity of the nasal septum and a positive ANCA profile for Wegener’s granulomatosis.
Subglottic stenosis, worsened (2 of 5)
Five months later, the symptoms became intolerable, and the stenosis was noted to be slightly narrower and with a greater posterior component. The patient agreed to dilation.
Subglottic stenosis, worsened (3 of 5)
Same exam as photo 2; this close-up view shows more clearly the inflammatory nature of this stenosis.
Subglottic stenosis, after dilation (4 of 5)
Five days after outpatient dilation, triamcinolone injection, and topical mitomycin C application. The patient’s symptoms have vanished, the harsh inspiratory noise is no longer heard, and the size of the airway, though still not normal, is more than doubled. Compare with photo 2 of this series.
Airway stenosis (1 of 5)
Marked inflammatory narrowing in the immediate subglottis. Within the ring of arrows is the inflamed, reddened tissue, which is narrowing the airway into the shape of a slit. This man needs to be active for his work, but notices shortness of breath and noisy breathing with exertion.
Airway stenosis, after dilation (2 of 5)
Nine days after a dilation procedure, with local steroid injection and painting with Mitomycin C. The airway has widened, so that it is more oval-shaped and less slit-like. Compare with photo 1. Although a degree of stenosis remains, symptoms have subsided dramatically. For reference, asterisks mark the same points in the subglottis in this photo and the next photo.
Airway stenosis, after dilation (3 of 5)
Same exam, looking beyond the immediate subglottis. There is an inflammatory response that involves several centimeters of the upper trachea. Inflammatory areas often “trap” mucus, as seen here.
Airway stenosis, before another dilation (4 of 5)
Now five months after the dilation procedure mentioned in photos 2 and 3. The patient has been receiving systemic treatment with methotrexate and prednisone. General appearance of the inflammation has decreased. In spite of this, as expected, the stenosis has persisted (dotted oval shows the estimated caliber or width of a normal airway) and symptoms have gradually increased. Thus, another dilation was scheduled for the next day.
Airway stenosis, after another dilation (5 of 5)
A week after photo 4, following the most recent dilation. There is expected immediate postoperative inflammation and an increase in the airway’s caliber or width by an estimated 30% (dotted oval again shows the estimated caliber or width of a normal airway; compare with photo 4). Symptoms are again abolished.
Diplophonia
Diplophonia is double pitch phonation. Often seen with vocal cord paralysis, and in submucosal disorders such as epidermoid cyst and glottic sulcus. Except for a type of luffing diplophonia that may be functionally produced, diplophonia tends to be a pathologic vocal phenomenon.
Disorder of vocal loudness perception
A lack of awareness or perception of one’s personal vocal “volume level” to the point that it is creating difficulty in one’s life. If asked to place oneself on a personal loudness scale from 1 to 7, most individuals can do so with reasonable accurateness. Occasionally, however, an individual (with normal hearing ability) lacks this kind of self-insight, and such an individual could be said to have a disorder of vocal loudness perception.
At one end of this spectrum was a patient who was an operatic tenor. He had a powerful, almost head-rattling voice even in close quarters in a quiet room, and he was aware that others thought him loud, but he clearly could not “relate” to this. When coaxed and coached repeatedly to use a moderate voice to read a passage out loud, he quite sincerely (and loudly!) said, “Oh, I could never do that! That’s whispering!” At the other end of the spectrum, there was a 30-something woman with a voice one had to strain to hear. When she was coaxed and coached to read the same passage with a moderately loud voice, her utterly sincere but almost whispered reply? “Oh, I couldn’t talk like that. That’s yelling.”
Vocal loudness can vary between individuals considerably and still be accepted as “within normal limits.” Yet the two individuals described above were considered to have a disorder of vocal loudness perception because their inappropriate vocal loudness was exceptional enough to cause life difficulty. The man had considerable vocal cord injury, and the young woman was struggling at her job, with customers who were occasionally angry about the impossibility of hearing her. The approach was the same with both of these individuals: both were asked to retrain their “set point” for personal vocal loudness by recruiting other people (and their ears) to the re-training task.
Dysphagia
Abnormal swallowing, or inability to swallow. Dysphagia can result from such diverse causes as surgery on the larynx or neck, stroke, the aging process, tumor, injury to the neck, or radiation, among other things.
Treatment for Dysphagia (Swallowing therapy):
This therapy is typically provided by a speech-language pathologist (and, more informally and adjunctively, by other healthcare professionals). General areas of teaching might include: choosing wisely which food types and consistencies to eat; swallowing maneuvers such as tucking the chin, double swallow, effortful swallow, head turning, and supraglottic swallow; and direct exercises for the tongue, pharynx, palate, and larynx.
Diet modification:
These are suggested dietary changes, particularly regarding food consistencies, directed at improving a patient’s ability to swallow and at avoiding aspiration. For example, an individual who is struggling with aspiration might be advised to avoid thin liquids and use thicker or carbonated liquids instead. Or this individual might be advised to avoid composite foods, since his or her swallowing deficiency could make it harder to “stay organized” with several consistencies in the mouth at once.
Photos:
Dysphagia / Delayed swallow reflex (1 of 3)
Panoramic view of laryngopharynx before administering blue-stained applesauce.
Dysphagia / Delayed swallow reflex (2 of 3)
Same view after first bolus of blue-stained applesauce. The vallecula fills with material before the swallow “happens”—signifying a delayed swallow reflex.
Cricopharyngeal dysfunction: before myotomy (1 of 2)
Lateral x-ray of the neck while swallowing barium (seen as a dark column). The non-relaxing cricopharyngeus muscle (light-grey bulge outlined by a dotted line) is causing narrowing of the upper esophageal passageway, as highlighted by the narrowed stream of dark barium at that point (arrow). Liquids and very soft foods can squeak through this narrow opening, but solid foods tend to get stuck.
Cricopharyngeal dysfunction: before myotomy (1 of 2)
Lateral x-ray of the neck while swallowing barium (the dark material seen here in the throat). The non-relaxing cricopharyngeus muscle (light-grey bulge outlined by a dotted line) is causing narrowing of the upper esophageal passageway, as highlighted by the narrowed stream of dark barium at that point (arrow). Liquids and very soft foods can squeak through this narrow opening, but solid foods tend to get stuck.
Dysphagia, due to tongue weakness (1 of 4)
Left tongue paralysis and atrophy (the left side is right of image), due to injury of the left hypoglossal nerve during neck surgery elsewhere. The tongue and its midline raphe (arrows) deviate to the atrophied side. This atrophied side of the tongue cannot “do its part” in the propulsive stage of swallowing.
Dysphagia, due to tongue weakness (2 of 4)
Hypopharyngeal pooling of saliva in the “swallowing crescent.” This pooling can suggest non-relaxation of the cricopharyngeus muscle as an additional swallowing impediment, though in this case a videofluoroscopic swallowing study does not confirm this hypothesis.
Dysphagia, due to tongue weakness (3 of 4)
After administration of blue-stained applesauce, the same hypopharyngeal pooling is seen, now of now-blue-stained saliva.
Dysphagia, due to tongue weakness (4 of 4)
This closer view within the larynx shows not only soiling of the laryngeal vestibule with saliva bubbles, but also a left contact granuloma (right of image). This injury could be the result of intubation four months earlier, or else of the continual coughing and throat clearing that occurs with this patient's swallowing disorder.
Post tonsillectomy (1 of 4)
A young woman struggles to swallow after extensive cauterization of severe bleeding after tonsillectomy elsewhere. The arrows here show the path food and liquid should follow to get into the esophagus (opening indicated by flat oval).
Closer view (2 of 4)
Closer view shows that the epiglottis is tethered to base of tongue at the dotted line. Furthermore, the "ski jump" scar appears to be ready to divert swallowed material directly into the larynx (arrow) rather than into the pyriform sinus at *.
Abnormal diversion (4 of 4)
While swallowing blue-colored water, arrows indicate the normal path on the left (right of photo) and the abnormal diversion into the larynx on the right (left of photo). The patient manages, but must swallow carefully, especially since the epiglottis cannot invert since it is scarred to the base of tongue as shown in photo 2.
Benign mass (1 of 4)
This elderly man is having a hard time swallowing solids. There is a mucosa-covered mass (marked with lines) between the posterior pharyngeal wall (longer dashed line) and the arytenoid towers (marked with A). "V" denotes the right vocal cord.
One week post-op (3 of 4)
This is a week after laser excision of this mass. The dashed line again shows the posterior pharyngeal wall and A and V again denote arytenoid apices and V, the right vocal cord. The pathology examination shows only fibrosis and other nonspecific benign findings.
Videos:
This video gives an overview of how swallowing works, how it can sometimes go wrong (presbyphagia or cricopharyngeal dysfunction), and possible ways to treat those problems (swallowing therapy or cricopharyngeal myotomy).
Dysphonia
Abnormal production of vocal sound; more commonly used as a synonym for hoarseness. Dysphonia may be the result of injury to the mucosa of the vocal cords; or it may be neurogenic, the result of a benign or malignant tumor; or it may be nonorganic.
Dystonia
A benign neurological disorder in which twisting and repetitive or sustained but unwanted muscle contraction occurs in a body part. It can affect a specific muscle (focal dystonia), a region of the body (regional dystonia), or even the body as a whole (generalized dystonia). Common focal dystonias include laryngeal (spasmodic dysphonia or respiratory dystonia); ocular (blepharospasm); neck or cervical (torticollis and related neck disorders); and limb dystonia (writer’s cramp). Treatment for focal dystonias is most commonly via Botox™ injection into affected muscles, and occasionally by selective denervation. More regional and generalized dystonias may respond to a variety of systemic medications such as clonazepam and others.
Dystonic tremor of the voice or larynx
A tremor that sometimes accompanies laryngeal dystonia and its effects on voice function (spasmodic dysphonia), breathing function (respiratory dystonia), or both. This dystonic tremor is heard as a “wavering” in the voice (if the person has spasmodic dysphonia) or in the sound of inhaled or exhaled air (if the person has respiratory dystonia), or it can be detected in both the voice and the sound of inhaled or exhaled air (if the person has both spasmodic dysphonia and respiratory dystonia). A patient who exhibits this kind of tremor in tandem with spasmodic dysphonia, for example, may be described by the examining clinician as having “spasmodic dysphonia with a small/moderate/large/overwhelming tremor component.” Dystonic tremor can also appear in other parts of the body (e.g., as head or limb movements) when a person’s dystonia affects those parts, but our focus here is on dystonia of the larynx.
Voice-affecting dystonic tremor might sometimes be mistaken for the tremor induced by a different neurological disorder, essential voice tremor. If one knows what to listen for, however, it is usually possible to distinguish dystonic tremor from the tremor induced by essential voice tremor. Most obviously, dystonic tremor is almost always accompanied by other manifestations of dystonia, such as phonatory arrests, dropouts to a whisper, or squeezedowns. Dystonic tremor may worsen under specific circumstances—with stress, fatigue, or during telephone use, for example. Dystonic tremor is often (though not always) more pronounced in the patient’s chest register voice than falsetto register voice—sometimes dramatically so—and this difference might be heard when the patient is asked to sustain a single sung note as steadily as possible. Finally, dystonic tremor’s amplitude can vary from cycle to cycle; to use singers’ parlance, it is as though a couple of cycles of “wild” vibrato are followed by a few cycles of merely wide vibrato, followed by a second or two of much more stable voice. In the occasional case, however, a patient’s tremor is so overwhelming and these distinctive qualities of dystonic tremor so subtle that the clinician proceeds initially with a working, rather than settled, diagnosis.