Projected voice is one that is perceptibly “thrown” or “called out,” as when talking to a group of 20 or more people. A clinician might ask a patient to project the voice during the vocal capability battery in order, for example, to reveal weakness not evident or only slightly apparent at normal speaking voice volume, to detect vocal inhibition, or to unmask a nonorganic voice disorder.

Laryngology 401: PCA-only Paresis, but the Actual Voice Problem Is Spasmodic Dysphonia

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Sense of instability (1 of 3)

This person had a major voice change after thyroidectomy for a large goiter. Within 2 months, voice recovered fully--except for a sense of instability. The PCA-only paresis is not the explanation because voice-making muscles (TA + LCA) are intact. And in fact vocal capability testing shows that both yell and projected voice are normal. The visual finding here of vocal cord bowing and capacious ventricle do not count as a breathing position finding with PCA-only paresis due to the unopposed action of LCA muscle, combined with an uncontracted TA muscle, both of which cause pseudo-bowing.

Vibratory amplitude (2 of 3)

During phonation under strobe light, with TA tensing, "bowing" disappears. Furthermore the vibratory "blur" at the margin of the left fold (right of photo) is equal to the right (left of photo), telling us that vibratory amplitude is approximately the same on both sides.

Spasm (3 of 3)

An audible/ visible spasm occurs when the right vocal cord jerks laterally for 4 frames (~ 1/8th of a second). The problem isn't PCA weakness on the left (right of photo), but instead an abductory spasm on the right (left of photo), fully mobile cord!