An investigation was conducted to determine radiation exposures to the head and neck regions of patients undergoing polytomographic studies of the sella turcica, paranasal sinuses, and petrous pyramid. The highest exposures were measured at the eyelid region for studies of the sella turcica and paranasal sinuses. In studies of the petrous pyramid, the highest exposures were recorded in the external auditory canals. Variation in the total number of exposures, the ratio of frontal and lateral exposures, and beam collimation are cided as principal causes of the wide range of values recorded for a given dosimeter location and type of examination. To reduce eye exposures, it is recommended that PA rather than AP projections be used for tomography of the petrous pyramid, sella turcica, sphenoid sinus, and other mid- and posteriorly-located structures of the skull. (Author)