Absorbed Doses and Energy Imparted From Radiographic Examination of Velopharyngeal Function During Speech

Abstract

Absorbed doses of radiation were measured by thermoluminescent dosime-ters (TLDs) using a skull phantom during simulated cinefluorographic and video-fluorographic examination of velopharyngeal function in frontal and lateral projections. Dosages to the thyroid gland, the parotid gland, the pituitary gland, and ocular lens were measured. Radiation dosage was found to be approximately 10 times less for videofluoroscopy when compared with that of cine-fluoroscopy. In addition, precautionary measures were found to reduce further the exposure of radiation-sensitive tissues. Head fixation and shielding resulted in dose reduction for both video-and cinefluoroscopy. Pulsing exposure for cinefluoroscopy also reduced the dosage.