A device for the rapid filming of the pharynx and cervical oesophagus.

Abstract

The extreme rapidity with which swallowing is completed makes the filming of the pharynx and cervical oesophagus with the customary spotfilming devices an uncertain and tiresome matter. It is in this region of the alimentary tract that cineradiography has great value since it provides a complete film record of the act of swallowing, but the high cost and restricted clinical applications of this method have precluded its use in a department limited in funds and space. At very small cost, a device has been constructed which is compact and easily fitted to many types of screening apparatus in current use, and which goes far in obviating the need for cineradiography of this particular region. With the device, ten frames of the pharynx and adjacent oesophagus can be obtained within 1·5 sec or at any longer interval of time which may be desired. Film and cassettes used in the device have the advantage of being of a standard size and require no special processing or projection equipment. The device (Fig. 1) has evolved on the principle that where the exposure time is sufficiently brief, the film on which the image is to fall can be travelling at limited speed during exposure without causing appreciable blur. The predicted blur of the image margins on a film travelling a distance of 30 in. in 3 sec is 0·2 in. with an exposure time of 0·02 sec.