V

velopharyngeal insufficiency Inadequate clo-
sure the velopharyngeal sphincter, a MUSCLEat the
back of the soft palate, that directs air flow to the
NOSEor to the MOUTH. Velopharyngeal insufficiency
often accompanies CLEFT PALATE/CLEFT PALATE AND
LIPanomalies and interferes with both speech and
swallowing. It also can occur as a complication of
tonsillectomy and adenoidectomy, operations to
remove the tonsils and ADENOIDS, respectively, and
of neurologic damage, such as from STROKE, that
restricts neuromuscular function of the pharynx.
The hallmark symptoms of velopharyngeal insuffi-
ciency are nasal speech and regurgitation food
into the back of the nose with swallowing. Some-
times the person has chronic or recurrent SINUSITIS
resulting from food particles becoming trapped in
the sinuses. The doctor may be able to feel a previ-
ously undiagnosed cleft in the hard palate beneath
an intact soft palate. ULTRASOUND or COMPUTED
TOMOGRAPHY(CT) SCANcan confirm the diagnosis.
Treatment for velopharyngeal insufficiency
when the cause is a structural anomaly begins
with surgery to restore sphincter function to the
extent possible. Operations may include repair of
a cleft palate or reconstructive surgery to extend
the soft palate (pharyngoplasty) to make the
velopharyngeal opening smaller. Most people sub-
sequently need speech therapy to retrain oral-
facial structures to form the sounds the
velopharyngeal insufficiency kept them from
properly making. These therapeutic interventions
typically restore complete function, though may
not be appropriate or successful when the cause of
the velopharyngeal insufficiency is neurologic
damage or a neuromuscular disorder.
See alsoOPERATION; SPEECH DISORDERS; SURGERY
BENEFIT AND RISK ASSESSMENT; SWALLOWING DISORDERS.

vertigo The perception of movement, usually

spinning, when none is taking place. Vertigo rep-

resents the body’s inability to accurately interpret

its position and movement within its environ-

ment. People with vertigo feel either that they are

moving or the setting around them is moving.

Vertigo occurs when the balance mechanisms of

the vestibular system, including the NERVEpath-

ways to the BRAIN, malfunction. The disturbance

can range from mild and brief to extended and

debilitating. Vertigo is a symptom of numerous

health conditions that can be vestibular (affecting

the structures of the inner EAR) or neurologic

(affecting the brain or nerves). Situations that

overstimulate the vestibular system, such as spin-

ning rapidly in circles (as in carnival rides) or

experiencing gravitational force (as in taking off in

a jet or a space shuttle), also often generate tem-

porary vertigo.

Causes of Vertigo

Vertigo develops when the brain receives conflict-

ing or incomplete information from the vestibular

system about the body’s orientation in its environ-

ment. This can occur because injury or disease

damages the structures of the vestibular system or

the parts of the NERVOUS SYSTEMthat convey bal-

ance and movement information to the brain.

Brain injury, such as from trauma or STROKE, that

affects parts of the brainstem involved in move-

ment also can result in vertigo.

Most commonly vertigo reflects dysfunction of

the vestibular system and the structures of the

inner ear. The semicircular canals, three fluid-

filled loops, detect rotational movements. The sac-

cule and the utricle, also fluid-filled chambers,

detect linear (horizontal and vertical) movements.

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