Facts on File Encyclopedia of Health and Medicine

(Jeff_L) #1

vocal cord nodule A noncancerous, fibrous
growth on the vocal cord, usually the result of
overusing the voice through repeated shouting,
singing, or public speaking. Vocal cord nodules
typically develop in book-matched pairs on the
folds of the VOCAL CORDSat points where the cords
vibrate in contact with each other. Nodules arise
from the epithelium, or surface layer of tissue,
that covers the vocal cords (unlike vocal cord
polyps, which arise from the mucous membrane
that forms the vocal cords). Vocal cord nodules
have the appearance of calluses and cause the
voice to take on a “breathy” quality, though some
people also experience hoarseness. The otolaryn-
gologist can remove vocal cord nodules through
the THROATusing endoscopic surgery. The surgical
wound takes about six weeks to heal, after which
VOICE THERAPYhelps the person learn methods to
protect the vocal cords and voice. Because vocal
cord nodules develop through overuse, they are
likely to recur with continued extensive speaking
or singing.
See also VOCAL CORD CYST; VOCAL CORD POLYP.


vocal cord paralysis The inability of the vocal
cord, a membranous flap of tissue in the larynx, to
open or close properly with the passage of air.
PARALYSISmay affect one vocal cord or both VOCAL
CORDS. Paralysis that affects both vocal cords is rare
and often affects BREATHING, as air cannot move
freely through the THROAT. Symptoms include
hoarseness, a “breathy” quality to the voice, dimin-
ished vocal volume, and occasionally throat PAIN.
Vocal cord paralysis often develops without an
identifiable cause, though also results from injury
to the throat or nerves that supply the throat, BRAIN
injury (such as trauma or from STROKE), and neuro-
logic conditions such as MULTIPLE SCLEROSIS and
PARKINSON’S DISEASE. People who use their voices
extensively, such as singers and teachers, are espe-
cially prone to vocal cord paralysis.
The diagnostic path typically includes laryn-
goscopy to examine the larynx and vocal cords.
Because vocal cord paralysis often goes away on
its own, doctors often take a watchful waiting
approach in combination with VOICE THERAPYto
improve voice function and quality. If the paraly-
sis continues, the otolaryngologist can inject a
bulking agent such as collagen into the paralyzed


cord. This closes the gap between the cords and
encourages both sets of cords to vibrate equally.
These measures improve, and often restore, vocal
cord function.
See also SPEECH DISORDERS; SWALLOWING DISOR-
DERS; VOCAL CORD CYST; VOCAL CORD NODULE; VOCAL
CORD POLYP.

vocal cord polyp A fleshy growth on the vocal
cord. Vocal cord polyps occur singly, rather than
paired as do vocal cord nodules, though more
than one polyp may be present. A polyp arises
from the mucous membrane that forms the VOCAL
CORDS; it grows out from the vocal cord on a stem-
like appendage, which allows the polyp to move
freely as the vocal cord vibrates. The location and
size of the polyp determine the ways that it inter-
feres with speech and hence its symptoms, which
can include a “breathy” quality to the voice,
hoarseness, difficulty “starting” the voice, and
sometimes loss of the voice.
Polyps develop as a result of irritation such as
from smoking, chronic POSTNASAL DRIP, environ-
mental pollutants, and allergic PHARYNGITIS. Because
polyps in other locations of the body, such as the
intestines and the SINUSES, occasionally become
cancerous, otolaryngologists recommend prompt
surgical removal. Most people fully recover within
four to six weeks. VOICE THERAPYcan teach methods
to preserve and protect the voice. Continued expo-
sure to the causative irritants, such as cigarette
smoke, is likely to result in recurrent polyps.
See also OCCUPATIONAL HEALTH AND SAFETY; OPERA-
TION; SMOKING AND HEALTH; VOCAL CORD CYST; VOCAL
CORD NODULE.

vocal cords A paired fold of thick, fibrous tissue
in the back of the larynx that vibrate with the pas-
sage of air to produce sounds. The vocal cords run
lengthwise in the larynx. Muscles that attach the
vocal cords to the larynx contract and relax to
change the tautness of the vocal cords, producing
variations in sound tone and volume. The vocal
cords relax during BREATHINGto allow free passage
of air through the larynx. The “talk test” for AERO-
BIC EXERCISEis an indirect measure of the volume
of air flowing through the THROAT: being unable to
speak during exercise means air flow is high
enough that the vocal cords cannot contract.

vocal cords 63
Free download pdf