Diagnostic evaluation of the breast using PET: Optimization of data acquisition and postprocessing

Purpose: Development and evaluation of on optimized protocol for PET examin ations of the female breast with 2-F-18-fluoro-2-deoxyglucose (F-18-FDG). M ethods: All PET measurements were performed with a whole-body PET system (E CAT EXACT HR+). in order to examine the women with the breasts freely penda nt, a special extension far the patient table mode of carbon layer composit e was designed. After data acquisition in the 3D modus, emission data were sorted into 2D sinograms using the Fourier rebinning algorithm and reconstr ucted by means of an ultra-fast iterative 2D algorithm (HOSP). The reconstr ucted emission scans were superimposed onto the corresponding transmission images. The protocol presented was evaluated in examinations on 6 women wit h breast lesions after the administration of 150-220 MBq F-18-FDG. From two adjacent bed positions, emission and transmission data were acquired over periods of 20 min and 10 min, respectively. For comparison dynamic magnetic resonance (MR) image series were acquired with a whole-body MR system (MAG NETOM SP 4000) using a double-breast coil. Results and Conclusion: Using th e designed extension of the patient table, it was possible to examine corpu lent women despite the limited patient port of the PET system in the prone position with the breasts freely pendant. Alongside a reduction in motion a rtifacts, this positioning also offers the possibility of making a direct c omparison between PET and MR images. Despite the fact that the amount of F- 18-FDG applied to the patient was markedly reduced, the combination of 3D d ata acquisition and iterative image reconstruction resulted in excellent qu ality of the emission scans. By superpositioning of iteratively reconstruct ed emission and transmission scans, anatomical localization of breast lesio ns visualized on the emission scans could be improved. The postprocessing o f the PET data described was completed in 60 min, this meaning that the pre sented concept con readily be employed in clinical practice.