Refers to the flaccid, flapping sound that occurs when more than the normal amount of air is passed between vocal cords, at least one of which is flaccid by virtue of a vocal cord paralysis or functional (non-organic) flaccidity. A breathy, diplophonic, unstable kind of vibration occurs that is characteristic of this laryngeal state. Luffing may not be heard if the individual is speaking very softly. It may often be elicited by asking the patient to phonate loudly. Once heard and identified, luffing is a quality easy for the uninitiated clinician to identify again.
Dr. Bastian’s example: