Radiation dose to the eyes and parotids during CT of the sinuses

OBJECTIVE: To measure the radiation dose to the lens and parotid during high-resolution computed tomography scan of the sinuses. STUDY DESIGN AND SETTING: Nine cadaver heads were scanned in the axial plane by means of a fine-cut (0.75 mm) protocol. Images were then reconstructed in the coronal and sagittal planes for use with the image guidance software. Thermoluminescent dosimeters were taped over the eyes and parotids and used to measure the radiation dose absorbed by these organs. RESULTS: Doses obtained were 29.5 mGy for the lens and around 30 mGy for the parotid. CONCLUSION: The measured doses are lower than the reported acute thresholds of 500-2000 mGy for lens opacities and well below the threshold of 2500 mGy for damage to the parotid. SIGNIFICANCE: These results demonstrate minimal risk from radiation through the use of high-resolution computed tomography and support the use of such a protocol for diagnosis and preoperative planning. (C) 2005 American Academy of Otolaryngology-Head and Neck Surgery Foundation, Inc. All fights reserved.