Improved Quantitative Parameter Estimation for Prostate T2 Relaxometry using Convolutional Neural Networks

Abstract

AbstractThis work seeks to evaluate multiple methods for quantitative parameter estimation from standard T2mapping acquisitions in the prostate. The T2estimation performance of methods based on neural networks (NN) was quantitatively compared to that of conventional curve fitting techniques. Large physics-based synthetic datasets simulating T2mapping acquisitions were generated for training NNs and for quantitative performance comparisons. Ten combinations of different NN architectures, training strategies, and training corpora were implemented and compared with four different curve fitting strategies. All methods were compared quantitatively using synthetic data with known ground truth, and further compared onin vivotest data, with and without noise augmentation, to evaluate feasibility and noise robustness. In the evaluation on synthetic data, a convolutional neural network (CNN), trained in a supervised fashion using synthetic data generated from naturalistic images, showed the highest overall accuracy and precision amongst all the methods. Onin vivodata, this best-performing method produced low-noise T2maps and showed the least deterioration with increasing input noise levels. This study showed that a CNN, trained with synthetic data in a supervised manner, may provide superior T2estimation performance compared to conventional curve fitting, especially in low signal-to-noise regions.