Key nob appearance is seen in:

Ans. C Phoneasthenia Ref. Dhingra 5th/ed p 334, 6th/ed p 3 74 Phonoasthemia is weakness of voice due to fatigue of phonatory muscles. either thyroarytenoids or intrarytenoids or both O/E - on Indirect laryngoscopy - 3 features may be seen Elliptical space between the cords in case of weakness of thyroarytenoid Triangular gap near posterior commissure in weakness of interarytenoid Keyhole appearance of glottis when both thyroarytenoids are involved.