OBJECTIVE: The present study was aimed at evaluating the effective radiation dose in patients submitted to PET/CT for the diagnosis of mild cognitive impairment. MATERIALS AND METHODS: TLD-100 detectors inserted into an Alderson Rando® anthropomorphic phantom were utilized to measure the absorbed dose coming from the CT imaging modality. The anthropomorphic phantoms (male and female adult versions) were submitted to the same technical protocols for patients' images acquisition. The absorbed dose resulting from the radiopharmaceutical injection was estimated by means of the model proposed by the ICRP publication 106. RESULTS: The effective dose in patients submitted to this diagnostic technique was approximately (5.34 ± 1.99) mSv. CONCLUSION: Optimized protocols for calculation of radioactive activity injected into patients submitted to this diagnostic technique might contribute to reduce the effective radiation dose resulting from PET/CT in the diagnosis of mild cognitive impairment.

Keywords: Dosimetry; PET/CT; Mild cognitive impairment.