Contrast dose reduction for medical imaging using deep learning

1. A method for training a diagnostic imaging device to perform medical diagnostic imaging with reduced contrast agent dose, the method comprising:

a) performing diagnostic imaging of a set of subjects to produce a set of images comprising, for each subject of the set of subjects,

i) a full-contrast agent dose image acquired with a full contrast agent dose administered to the subject,

ii) a low-contrast agent dose image acquired with a low contrast agent dose administered to the subject, where the low contrast agent dose is less than the full contrast agent dose, and

iii) a zero-contrast agent dose image acquired with zero contrast agent dose administered to the subject;

b) pre-processing the set of images to co-register and normalize the set of images to adjust for acquisition and scaling differences between different scans;

c) training a deep learning network (DLN) with the pre-processed set of images by

applying zero-contrast agent dose images acquired with zero contrast agent dose from the set of images and low-contrast agent dose images acquired with low contrast agent dose from the set of images as input to the DLN and

using a cost function to compare the output of the DLN with full-contrast agent dose images acquired with full contrast agent dose from the set of images to train parameters of the DLN using backpropagation.

2. The method of claim 1 wherein the cost function is an MAE loss function, or a mixture loss function with non-local structural similarities.

3. A method for medical diagnostic imaging with reduced contrast agent dose, the method comprising:

a) performing diagnostic imaging of a subject to produce

a low-contrast agent dose image acquired with a low contrast agent dose administered to the subject, where the low contrast agent dose is less than a full contrast agent dose, and

a zero-contrast agent dose image acquired with zero contrast agent dose administered to the subject;

wherein the low-contrast agent dose image and the zero-contrast agent dose image are acquired using a common imaging modality;

b) pre-processing the low-contrast agent dose image and zero-contrast agent dose image to co-register and normalize the images to adjust for acquisition and scaling differences;

c) applying the low-contrast agent dose image and the zero-contrast agent dose image as input to a deep learning network (DLN) to generate as output of the DLN a synthesized full-dose contrast agent image of the subject;

wherein the DLN has been trained by applying zero-contrast agent dose images and low-contrast agent dose images as input and full-contrast agent dose images as reference ground-truth images.

4. The method of claim 3 wherein

the low contrast agent dose is less than 10% of a full contrast agent dose.

5. The method of claim 3 wherein

performing diagnostic imaging comprises performing angiography, fluoroscopy, computed tomography (CT), ultrasound, or magnetic resonance imaging.

6. The method of claim 3 wherein

performing diagnostic imaging comprises performing magnetic resonance imaging, and the full contrast agent dose is at most 0.1 mmol/kg Gadolinium MRI contrast.

7. The method of claim 3 wherein

the DLN is an encoder-decoder convolutional neural network (CNN) including bypass concatenate connections and residual connections.

8. A method for medical diagnostic imaging, the method comprising:

a) performing diagnostic imaging of a subject to produce

a first image acquired with a first image acquisition sequence and

a second image acquired with a second image acquisition sequence distinct from the first image acquisition sequence,

where zero contrast agent dose is administered during the diagnostic imaging;

wherein the first image and the second image are acquired using a common imaging modality;

b) pre-processing the first image and the second image to co-register and normalize the images to adjust for acquisition and scaling differences;

c) applying the first image and the second image as input to a deep learning network (DLN) to generate as output of the DLN a synthesized full-dose contrast agent image of the subject;

wherein the DLN has been trained by

applying as input to the DLN zero-contrast agent dose images acquired with different imaging sequences and with a full contrast agent dose administered and

using full-contrast agent dose images acquired with a full contrast agent dose administered as reference ground-truth images.