Cinefluorographic study of pharyngeal function related to speech.

Abstract

Cinefluorography, utilizing an image intensifier and a camera that permits the simultaneous optical recording of sound, offers a technic for the visualization of the movements of the palate, tongue, and pharyngeal soft tissues during speech. The record obtained is a permanent one with which subsequent examinations may be compared. The technic is not unique. Cooper in 1955 reported on the use of cinefluorography in the fields of plastic surgery, dentistry, and speech. In his initial study, sound was recorded on a magnetic tape during cinefluorography and subsequently added to the film record; later, he employed optical recording of sound. Both optical and magnetic recording result in sound synchronous with the motions of the oral and pharyngeal structures. Optical recording is less complicated in that the sound track is exposed directly on the film and developed with the pictures. The apparatus in use at St. Christopher's Hospital for Children (Philadelphia) is illustrated in Figure 1. There are three basic units: a conventional fluoroscopic tube, table, and tower; an image intensifier of the electron optical type manufactured by the North American Philips Co., Inc., a 16-mm. “sound on film” camera (Auricon Cine-Voice II). The camera is equipped with a 25-mm. f.95 lens focused at infinity. With the fluoroscopic table in the upright position, the patient sits on the foot rest so that the pharynx is viewed in the lateral projection. A microphone is held 12 to 18 inches from the patient. Motion pictures are exposed at the rate of 24 frames per second as the patient speaks. Another exposure is made as the patient swallows a barium and water mixture to demonstrate regurgitation into the nasal cavity. It has not been necessary to use contrast material for visualization of the intra-oral and pharyngeal structures; the air around them is sufficient. The patient is exposed to the x-ray beam (a circle 5 inches in diameter) for forty-five to sixty seconds. This produces 30 to 35 feet of exposed film with 1,000 to 1,500 individual frames available for study. The amplifier for the camera is so constructed that soundtrack exposure is calibrated and hence is reproducible at subsequent examinations. Tone may be controlled and, when children are being examined, it is helpful to increase the volume of the low frequencies. There is a need for increased knowledge of the motor activities of the lips, tongue, mandible, soft palate, and pharyngeal soft tissues during speech and of their relation to the production of speech in both the normal and abnormal oral cavity and pharynx. As Calnan has observed, the physician is at a disadvantage in the examination of patients with abnormalities of the palate, pharynx, or abnormal speech.