Laryngeal stroboscopy uses a synchronized flashing light passed through either a rigid or flexible laryngoscope to provide an image of the vocal fold motion; the image is created by averaging over several vibratory cycles and is thus not provided in real-time. As this technique relies on periodic vocal fold vibration, it cannot be used in patients with moderate to severe dysphonia. High speed digital imaging of the vocal folds (videokymography), another imaging technique, is not subject to the same limitations as laryngeal stroboscopy. A rigid endoscope is used to take images at a rate of 8000 frames per second, and the image is displayed in real time. As well, this technique allows imaging of aperiodic vibrations and can thus be used with patients presenting with all severities of dysphonia. Acoustic measures
Acoustic measures can be used to provide objective measures of vocal function. Signal processing algorithms are applied to voice recordings made during sustained phonation or during spontaneous speech. The acoustic parameters which can then be examined include fundamental frequency, signal amplitude, jitter, shimmer, and noise-to-harmonic ratios. However, due to limitations imposed by the algorithms employed, these measures cannot be used with patients who exhibit severe dysphonia. Aerodynamic measures
Aerodynamic measures of voice include measures of air volume, air flow and sub glottal air pressure. The normal aerodynamic parameters of voice vary considerably among individuals, which leads to a large overlapping range of values between dysphonic and non-dysphonic patients. This limits the use of these measures as a diagnostic tool.
Nonetheless, they are useful when used in adjunct with other voice assessment measures, or as a tool for monitoring therapeutic effects over time. Prevention
Given that certain occupations are more at risk for developing dysphonia (e.g. teachers) research into prevention studies have been conducted. Research into the effectiveness of prevention strategies for dysphonia have yet to produce definitive results, however, research is still ongoing. Primarily, there are two types of vocal training recognized by professionals to help with prevention: direct and indirect. Direct prevention describes efforts to reduce conditions that may serve to increase vocal strain (such as patient education, relaxation strategies, etc. ), while indirect prevention strategies refer to changes in the underlying physiological mechanism for voice production (e.g., adjustments to the manner in which vocal fold adduction occurs, respiratory training, shifting postural habits, etc.). Treatment
Although there is no universal classification of voice problems, voice disorders can be separated into certain categories: organic (structural or neurogenic), functional, neurological (psychogenic) or iatrogenic, for example. Depending on the diagnosis and severity of the voice problem, and depending on the category that the voice disorder falls into, there are various treatment methods that can be suggested to the patient. The professional has to keep in mind there is not one universal treatment, but rather the clinical approach must find what  the optimal effective course of action for that particular patient is.There are three main type of treatments: medical treatments, voice therapy and surgical treatments. When necessary, certain voice disorders use a combination of treatment approaches.