Skip to Main Content


The purpose of a clinical voice evaluation is to provide the referring laryngologist with patient-specific, clinically relevant pathophysiologic information of the actual voice production process used by the dysphonic patient, the nature of the dysphonic sound generated by a patient, and the physiologic conditions responsible for the sound production. The generated report must be clear and explanatory enough to aid the referring laryngologist with differential diagnosis and treatment planning. Moreover, the generated information must be capable of predicting treatment outcomes and powerful enough to warn the treating physician of any possible complications to the voice that may result from the proposed or planned treatment—whether medical, surgical, therapeutic, or a combination. Clinical voice evaluation is not a quick procedure. It may take up to 1 hour to conduct phonatory function studies (PhFS) on a noncomplicated patient, whereas it may take a substantially longer time to evaluate a patient who is a professional voice user.


The clinical exam comprises a battery of PhFS composed of at least of two primary parts: (1) an acoustic portion that examines the nature of the generated sound (CPT 92520 and 92506), and (2) a visual portion that examines via stroboscopic transoral or transnasal approach the glottis and surrounding area including the subglottis. Visualization of the subglottis is of paramount clinical value when examining papilloma, trauma, and/or subglottic stenosis patients. The exam must result in a clinically relevant description of the parameters that specify and regulate the vibratory patterns of the vocal cords and/or the other vocal tract elements that are causative of dysphonia. This portion of the exam is coded as 31579 using CPT code. (Note: When examining alaryngeal patient, or when utilizing other procedures or tests, additional CPT codes apply.)


Phonatory Function Studies (Phfs)


PhFS are considered a standard of modern voice care because they provide information beyond subjective clinical impressions; they also provide objective descriptions of normal and pathologic phonatory processes. These processes include (1) mapping acoustic voice characteristics, (2) correlating voice with physiologic findings, (3) providing guidelines for the development of efficacious treatment plans, (4) predicting the progress and outcomes of treatment plans, (5) providing preoperative–postoperative lesion mappings, and (6) providing documentation for medicolegal purposes. PhFS are reproducible and allow a contrast of individual results to a database specific to the patient's age and gender. The information these studies provide also allows for a frank discussion with the patient and education of the patient, including discussion of the risks and alternatives associated with various treatments.


The acoustic portion (92520 with the various modifiers used) records and analyzes the voice of the patient. This portion is of paramount value, specifically when a surgical intervention is planned and when the patient uses voice as a tool of labor. Not having a voice recording of a patient as a part of record is simply inexcusable and must be treated as a serious error on the part of the practicing ...

Want remote access to your institution's subscription?

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.


About MyAccess

If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.

Subscription Options

AccessSurgery Full Site: One-Year Subscription

Connect to the full suite of AccessSurgery content and resources including more than 160 instructional videos, 16,000+ high-quality images, interactive board review, 20+ textbooks, and more.

$995 USD
Buy Now

Pay Per View: Timed Access to all of AccessSurgery

24 Hour Subscription $34.95

Buy Now

48 Hour Subscription $54.95

Buy Now

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.