Diagnosis of Voice Disorders
Medical diagnosis is performed with state-of-the-art equipment at the UNC Voice Center. Equipment includes:
- Videolaryngostroboscopy - This equipment allows for slow motion viewing of the vocal folds (which move faster than the human eye is capable of seeing). Research shows that videostroboscopy contributes significant diagnostic information in 27% of vocal fold abnormalities and that 10% of diagnoses made by referring physicians are changed when the vocal folds are viewed by this procedure (Peak Woo et al, 1991).
- Acoustic Analysis - The Kay Elemetric CSL (Computerized Speech Laboratory) allows for quantification of perceptual and behavioral abnormalities, include vocal fold pitch, pitch range, amount of vocal fold variability, amount of "noise" in the sound, etc.
- Aerodynamic Measures - Two types of equipment are used in this laboratory for airflow measures, the Kay Elemetrics Aerophone II Program and the Tamarac Presto Flash Spirometry Unit. (Of course, not all measures will be appropriate or necessary for all patients.) These programs provide information about lung capacity, amount of airflow used during sustained vowels and the amount of resistance the vocal folds are providing to airflow coming from the lungs.
- Spectral Displays - These are acoustic "pictures" of one's voice and provide a visual print out of individual voices. Waveform displays include wide and narrow band.
- Electroglottography (EGG) - EGG waves give a visual picture of vocal fold contact during the glottal cycle. This diagnostic information is useful in completing the picture of what the vocal folds are doing during phonation (using the voice).
- Nasometer - The Kay Elemetrics Nasometry program is useful in the diagnosis of patients with velopharyngeal abnormalities, i.e. disorders of how the soft palate closes off the nasal cavities. Excessive flow through the nose results in a perceptually hypernasal sound. (These measures may not be appropriate for all patients with voice problems.)
How Can a Voice Disorder Be Treated?
Most voice disorders do not require surgical intervention. They can be dramatically improved by the intervention of a speech pathologist knowledgeable and experienced in voice therapy strategies. At other times, medications for allergies, asthma, Gastroesophageal Reflux Disease or other conditions may be prescribed. Voice therapy is often suggested in conjunction with the use of prescription medications. This is because it is not uncommon for individuals to develop maladaptive behaviors in an attempt to compensate for their voice difficulties. Maladaptive behaviors may include (but are not limited to) throat clearing, adding excessive musculo-skeletal tensions, and using an inappropriate pitch or loudness. These behaviors may actually serve to perpetuate the disorder, even when medications have decreased the underlying etiology (cause) or the problem.
When Should a Voice Disorder Be Treated Surgically?
This is the decision of the surgeon, often made in conjunction with voice care team members. Some voice disorders may not respond to voice therapy. If after a short course of voice therapy, improvement is not enough to satisfy the patient, otolaryngologist, and speech pathologist, surgical intervention may be necessary. Follow-up speech / voice therapy is usually critical to the healing process. Surgical intervention would include, but is not limited to the following diagnoses. A large variety of surgical instruments and techniques are available for microlaryngeal surgery. Specific techniques should discussed with your otolaryngologist when surgery in necessary.
- When there is any possibility that vocal problems may be due to a tumor, then a biopsy would be necessary.
- Benign growths, such as papillomas, are often best removed with a carbon dioxide laser.
- Vocal fold polyps which fail to respond to speech therapy, may require surgical excision, as may cysts of the vocal folds.
- Bowing of the vocal folds is sometimes treated by injection of substances, such as fat.
- Some cases of unilateral vocal fold paralysis are treated with surgical procedures through the neck to place implants beneath the vocal fold to push them more medially.
- Some cases of bilateral vocal fold paralysis are treated by laser excision of one arytenoid cartilage to increase the size of the airway.