Roentgen Evaluation of Velopharyngeal Closure

Abstract

Roentgen methods are available for the evaluation of the pharyngeal structures and particularly for the evaluation of velopharyngeal closure. Velopharyngeal closure may be estimated by indirect methods; for example , the nasal emission of air and, of course, the study of the patient's speech. In addition, the palate and uvula may be examined directly. There are, however, large gaps in our current knowledge of the physiology of the pharyngeal structures, in the growth and development of the pharynx, and in the relationship of function to altered oral, nasal or pharyngeal anatomy. Pruzansky (3) has compared the development and growth of knowledge of anomalies of the face to knowledge of anomalies of the heart. In his opinion, the surgeon, orthodontist, and speech therapist are denied pathological specimens and are denied precise knowledge of the normal and of the abnormal. From the roentgen standpoint, the difference has to do with the appreciation of anatomic alterations as reflections of functional alterations and vice versa. Roentgen techniques have proven valuable in the study of the pharyn-geal structures, even though there are significant limitations. Direct examination of the pharynx as one structure is difi'icult or impossible to obtain without distortion of anatomy. Direct examination, of course, of any one of the pharyngeal structures is possible. The oral cavity and pharynx, because of their anatomy, are ideally suited to roentgen examination. Any structure is visible radiographically because of its physical properties and in the pharynx the radiographic contrast afforded by bone, soft tissues, and air allows for visualization of the structures composed of soft tissue and surrounded by air as well as those composed of bone. Thus, the soft palate and uvula may readily be visualized and their relationship to the posterior pharyngeal wall be studied. The application of any radiographic technique must be tempered by the knowledge that ionizing radiation is being utilized and appropriate steps, from the standpoint of protection of the patient and the physician, must be taken. Such steps include appropriate cones, proper filtration