Larynx synchronised stroboscopy--a new tool for outcome measures in the voice clinic.

Direct vocal fold synchronised stroboscopy is a new technique for obtaining useful images of pathological voice, with reduced requirements for both vocal fold cycle regularity and the duration of sustained phonation. Precise synchronisation of the firing of the stroboscope from the Laryngograph waveform, and the capture of images and waveforms into a computer, allows inspection of short periods of phonation (less than one second) as a continuous replay of the images. Replay can be continued indefinitely, automatically repeating the short period of image capture, eliminating the need to rewind a video-tape repetitively. This in turn avoids the need for the lengthy phonation otherwise required when clinical examination is based on the use of conventional live or video-taped stroboscopy. Since the LxStrobe system is based on digital processing, archiving and retrieval of images is much enhanced. A demonstration of the system, called the LxStrobe, is available on the world-wide-web at www.laryngograph.com.