Background Evaluation of left atrium (LA) remodeling is becoming increasingly relevant in understanding several pathological cardiac conditions. 18F-FDG-PET/computed tomography (CT), the current gold standard for metabolic evaluation of the left… Click to show full abstract
Background Evaluation of left atrium (LA) remodeling is becoming increasingly relevant in understanding several pathological cardiac conditions. 18F-FDG-PET/computed tomography (CT), the current gold standard for metabolic evaluation of the left ventricle, could be extended to LA using the latest PET technologies. We sought to perform a phantom study to optimize the reconstruction algorithm in this context. Methods The liver, heart cavity and walls of an anthropomorphic phantom were filled with typical patient 18F-FDG activity concentrations. Acquisitions were performed on an analog and on a digital TOF-PET/CT, and reconstructed with and without resolution recovery (RR). The Richardson-Lucy RR method was used, either through a third-party software or through the PET/CT manufacturer algorithm. Activity recoveries in the atria and ventricles and signal-to-noise ratios were evaluated to identify the best reconstruction and RR parameters. The same methodology was applied on a patient cardiac study. Results Analog PET/CT with the third-party RR cannot improve the activity recovery without markedly degrading the image quality. For the digital PET/CT, the optimal algorithm was the manufacturer RR reconstruction using four iterations and 15 subsets combined with five RR iterations. This reconstruction improved the LA activity recovery from 58% to 70% while preserving images of diagnostic quality. Similar results were obtained for the patient study. Conclusion The digital TOF-PET/CT with the identified optimal reconstruction can be used to quantitatively analyze the LA uptake in 18F-FDG cardiac studies while still preserving image reading quality. This may lead to more precise cardiovascular disease status evaluation, especially when atria are concerned.
               
Click one of the above tabs to view related content.