For the past three years we have been employing a satisfactory simple technic for photographing the larynx in action. The results of our earliest efforts were first shown by Dr. George M. Coates at the meeting of the American Academy of Ophthalmology and Otolaryngology in 1935.
The method to be described has three important features to recommend it. First, it requires no expensive or unusual apparatus; second, photographs are obtained with the area under local anesthesia so that laryngeal movements can be recorded, and third, the photographs are taken during routine examination or treatment, with a loss of time not exceeding one or two minutes.
Anesthesia is accomplished by the use of a 10 per cent solution of cocaine hydrochloride applied locally to the larynx as for any direct laryngoscopy or bronchoscopy. The patient reclines on the operating table; the head is held by an assistant, and the direct laryngoscope