| CPC G06V 10/764 (2022.01) [G06T 3/4053 (2013.01); G06T 11/008 (2013.01); G06V 10/774 (2022.01); G06V 10/82 (2022.01); G06T 2207/10088 (2013.01); G06T 2207/20081 (2013.01); G06T 2207/20084 (2013.01)] | 1 Claim |

|
1. A deep learning-based method for generating 7T magnetic resonance (MR) images from 3T MR images, comprising the following steps:
Step 1: constructing a training dataset which comprises multiple training sample pairs, each pair including a paired 3T image xi and real 7T image yi, where “i” denotes the index of the training sample pair;
Step 2: constructing a deep learning model which comprises:
a generator, configured to take a 3T image xi as input and output a synthetic 7T image ŷi;
a spatial alignment network (SAN) module, configured to: take the synthetic 7T image ŷi and a real 7T image yi as inputs; compute a displacement field Ø between the synthetic 7T image ŷi and the real 7T image yi; apply a spatial transformation to the synthetic 7T image ŷi based on the displacement field Ø to obtain a spatially aligned synthetic 7T image yi; and
a discriminator, configured to distinguish between synthetic image pairs (xi,yi) and real image pairs (xi,yi);
Step 3: constructing loss functions for the generator and the discriminator of the deep learning model;
Step 4: training the deep learning model using backpropagation and gradient descent, such that: the discriminator maximizes a probability of assigning correct labels to the spatially aligned synthetic 7T image yi and the real 7T image yi that are inputted; and the difference between the synthetic 7T image and the real 7T image is minimized, resulting in a trained deep learning model;
the generator's loss function LG(θ) is defined by the following formula:
![]() where, | |1 denotes the L1 norm; N is the total number of training sample pairs; D(⋅, θD) represents the discriminator, where ⋅ denotes the input and θD denotes the discriminator's network parameters; α and β are weighting coefficients for the adversarial loss and smoothness loss, respectively; ∇Ø denotes the gradient of the displacement field;
the discriminator's loss function is defined by the following formula:
![]() |