Laryngeal Imaging Flashcards
5 Histological Layers of the Vocal Fold
Epithelium Superficial lamina propria Intermediate lamina propria Deep lamina propria Thyroarytenoid (TA) muscle
Visualization Techniques
Mirror Rigid or Flexible Endoscopy w/o stroboscopy Laryngeal videostroboscopy Videokymography High speed digital imaging
Stroboscopy Principles
uses pulsed light to aid visualization of moving object
flicker-free uniformly illuminated background
perception of motion when none exists
Continuous light
shows adduction and abduction
Strobed light
allows us to “see” vibration of folds
Flex Stroboscopy
allows you to see running speech, swallowing
normal phonation visualization
Rigid Stroboscopy
better for assessing signs of reflux
Videokymography
inexpensive method to examine vocal fold vibration regardless of periodicity of vibration
modified CCD video camera
records a single line of the CCD chip 8000 line images/sec
real time visualization of vocal fold vibration
Videokymography (how it works)
left-right asymmetries
open quotient
propagation of mucosal wave
anteroposterior modes of VF vibration
Measurements from Videokymography
ratio between the aplitudes of both the vocal folds
ratio between the periods of the two folds
ratio between duration of the open and closed phase of glottal cycle
High-Speed Imaging
possible to assess actual cycle-to-cycle variations in VF motion
view vibration regardless of periodicity of voice
superior at assessing vibratory asymmetries and effect of pathologies on vocal fold vibration
Components of stroboscopy
strobe computer scope microphone electroglottagraph
What can we evaluate with LVS?
vocal fold edge, amplitude, horizontal phase and vertical phase of mucosal wave, non-vibrating poritons supraglottic activity vertical level phase closure symmetry periodicity or regularity closure pattern
Four M’s
mucosa
movement
mass
mucosal wave
