Three-dimensional CT imaging method and apparatus
The disclosure provides a three-dimensional CT imaging method and apparatus. The method includes: collecting two DR images with a perpendicular relationship for an object to be imaged; inputting the two DR images into a preset three-dimensional volume reconstruction model to obtain a three-dimensional volume of the object outputted by the three-dimensional volume reconstruction model; and slicing the three-dimensional volume to obtain three-dimensional CT imaging of the object, wherein the preset three-dimensional volume reconstruction model is trained using multiple training samples, each training sample comprising: a DR image group composed of two DR images with a perpendicular relationship, a pseudo-sinogram corresponding to the DR image group, and a three-dimensional volume corresponding to the DR image group.
1 . A three-dimensional computed tomography (CT) imaging method based on X-ray dual projection, comprising:
collecting two digital radiography (DR) images with a perpendicular relationship for an object to be imaged;
obtain a three-dimensional volume of the object to be imaged corresponding to the two DR images with a perpendicular relationship based on a preset three-dimensional volume reconstruction model; and
slicing the three-dimensional volume to obtain three-dimensional CT imaging of the object to be imaged,
wherein, generating the preset three-dimensional volume reconstruction model comprises:
obtaining a training data set; wherein the training data set is composed of DR images of reference objects collected circumferentially;
training to-be-trained three-dimensional volume reconstruction model using DR images with a perpendicular relationship in the training data set to obtain the preset three-dimensional volume reconstruction model;
wherein, when obtaining the training data set, the method further comprises:
obtaining a reference three-dimensional volume and a reference pseudo-sinogram of each of the reference objects based on the training data set; wherein the reference pseudo-sinogram is obtained by stacking collected DR images of a same reference object into a three-dimensional matrix according to a collection order, summing sinograms in each layer column by column, and normalizing a sum result;
dividing the DR images of each reference object in the training data set into a plurality of DR image groups, and each of the DR image groups comprises two DR images with a perpendicular relationship;
wherein the training to-be-trained three-dimensional volume reconstruction model using DR images with a perpendicular relationship in the training data set to obtain the preset three-dimensional volume reconstruction model comprises:
inputting the plurality of DR image groups into the to-be-trained three-dimensional volume reconstruction model, training the to-be-trained three-dimensional volume reconstruction model, and respectively obtaining a training pseudo-sinogram and a training three-dimensional volume;
calculating a loss value based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram and the reference three-dimensional volume according to a training order;
terminating the training and obtaining the preset three-dimensional volume reconstruction model in a case that any calculated loss value is less than a target loss value, or the number of training times reaches a target number of times.
2 . The method according to claim 1 wherein the to-be-trained three-dimensional 1 volume reconstruction model comprises an enhancement network model and a reconstruction network model;
the enhancement network model is a model based on an encoder-decoder network architecture, and configured to input a DR image group with a perpendicular relationship and output a corresponding training pseudo-sinogram; and
the reconstruction network model is an autoencoder network model for two-dimensional to three-dimensional volume mapping and configured to input the training pseudo-sinogram and output a corresponding training three-dimensional volume.
3 . The method according to claim 2 , wherein the enhancement network model to input a DR image group with a perpendicular relationship, and output a corresponding training pseudo-sinogram, comprises:
performing pattern and feature
extraction on the inputted DR image group, and performing a cascade operation on a results of the extraction;
performing latent space feature encoding on features after the cascade operation to obtain encoded latent space features; and
decoding the encoded latent space features to obtain the training pseudo-sinogram.
4 . The method according to claim 2 , wherein the reconstruction network model to input the training pseudo-sinogram, and output a corresponding training three-dimensional volume, comprises:
performing feature capture and enhancement on the input training pseudo-sinogram;
encoding a result of feature enhancement, and continuously reducing the spatial resolution on the basis of keeping the number of channels unchanged; and
decoding a result of the encoding, and continuously restoring the spatial resolution to a spatial resolution of the reference three-dimensional volume to obtain the training three-dimensional volume.
5 . The method according to claim 1 , wherein the calculating a loss value based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume according to the training order, comprises:
calculating the loss value using a preset loss function based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume,
wherein the preset loss function is a function of a weighted summation of a first loss function and a second loss function; the first loss function is configured to calculate a mean square error loss between a training pseudo-sinogram and a reference pseudo-sinogram, and the second loss function is configured to calculate a mean square error loss of a training three-dimensional volume and a reference three-dimensional volume.
6 . The method according to claim 2 , wherein the calculating a loss value based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume according to the training order, comprises:
calculating the loss value using a preset loss function based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume,
wherein the preset loss function is a function of a weighted summation of a first loss function and a second loss function; the first loss function is configured to calculate a mean square error loss between a training pseudo-sinogram and a reference pseudo-sinogram, and the second loss function is configured to calculate a mean square error loss of a training three-dimensional volume and a reference three-dimensional volume.
7 . The method according to claim 3 , wherein the calculating a loss value based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume according to the training order, comprises;
calculating the loss value using a preset loss function based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume,
wherein the preset loss function is a function of a weighted summation of a first loss function and a second loss function; the first loss function is configured to calculate a mean square error loss between a training pseudo-sinogram and a reference pseudo-sinogram, and the second loss function is configured to calculate a mean square error loss of a training three-dimensional volume and a reference three-dimensional volume.
8 . The method according to claim 4 , wherein the calculating a loss value based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume according to the training order comprises:
calculating the loss value using a preset loss function based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume,
wherein the preset loss function is a function of a weighted summation of a first loss function and a second loss function: the first loss function is configured to calculate a mean square error loss between a training pseudo-sinogram and a reference pseudo-sinogram, and the second loss function is configured to calculate a mean square error loss of a training three-dimensional volume and a reference three-dimensional volume.
9 . A three-dimensional computer tomography (CT) imaging device based on X-ray dual projection, comprising:
a storage unit, configured to store a preset three-dimensional volume reconstruction model; generating the preset three-dimensional volume reconstruction model comprises: obtaining a training data set; wherein the training data set is composed of digital radiography (DR) images of reference objects collected circumferentially; training to-be-trained three-dimensional volume reconstruction model using DR images with a perpendicular relationship in the training data set to obtain the preset three-dimensional volume reconstruction model;
an acquisition unit, configured to collect two DR images with a perpendicular relationship for an object to be imaged;
an obtaining unit, configured to obtain a three-dimensional volume of the object to be imaged corresponding to the two DR images with a perpendicular relationship based on the preset three-dimensional volume reconstruction model; and
an imaging unit, configured to slice the three-dimensional volumes to obtain three-dimensional CT imaging of the object to be imaged,
wherein, generating the three-dimensional volume reconstruction model stored in the storage unit comprises:
when obtaining the training data set, obtaining a reference three-dimensional volume and a reference pseudo-sinogram of each of the reference objects based on the training data set; wherein the reference pseudo-sinogram is obtained by stacking collected DR images of a same reference object into a three-dimensional matrix according to a collection order, summing sinograms in each layer column by column, and normalizing a sum result;
dividing the DR images of each reference object in the training data set into a plurality of DR image groups, and each of the DR image groups comprises two DR images with a perpendicular relationship;
inputting the plurality of DR image groups into the to-be-trained three-dimensional volume reconstruction model, training the to-be-trained three-dimensional volume reconstruction model, and respectively obtaining a training pseudo-sinogram and a training three-dimensional volume;
calculating a loss value based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram and the reference three-dimensional volume according to a training sequence;
terminating the training and obtaining the preset three-dimensional volume reconstruction model in a case that any calculated loss value is less than a target loss value, or the number of training times reaches a target number of times.
10 . An electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable by the processor, the processor is configured to execute the computer program to implement a three-dimensional computed tomography (CT) imaging method based on X-ray dual projection, the method comprises:
collecting two digital radiography (DR) images with a perpendicular relationship for an object to be imaged;
obtain a three-dimensional volume of the object to be imaged corresponding to the two DR images with a perpendicular relationship based on a preset three-dimensional volume reconstruction model; and
slicing the three-dimensional volume to obtain three-dimensional CT imaging of the object to be imaged,
wherein, generating the preset three-dimensional volume reconstruction model comprises:
obtaining a training data set; wherein the training data set is composed of DR images of reference objects collected circumferentially;
training to-be-trained three-dimensional volume reconstruction model using DR images with a perpendicular relationship in the training data set to obtain the preset three-dimensional volume reconstruction model;
wherein, when obtaining the training data set, the method further comprises:
obtaining a reference three-dimensional volume and a reference pseudo-sinogram of each of the reference objects based on the training data set; wherein the reference pseudo-sinogram is obtained by stacking collected DR images of a same reference object into a three-dimensional matrix according to a collection order, summing sinograms in each layer column by column, and normalizing a sum result;
dividing the DR images of each reference object in the training data set into a plurality of DR image groups, and each of the DR image groups comprises two DR images with a perpendicular relationship;
wherein the training to-be-trained three-dimensional volume reconstruction model using DR images with a perpendicular relationship in the training data set to obtain the preset three-dimensional volume reconstruction model comprises:
inputting the plurality of DR image groups into the to-be-trained three-dimensional volume reconstruction model, training the to-be-trained three-dimensional volume reconstruction model, and respectively obtaining a training pseudo-sinogram and a training three-dimensional volume;
calculating a loss value based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram and the reference three-dimensional volume according to a training order;
terminating the training and obtaining the preset three-dimensional volume reconstruction model in a case that any calculated loss value is less than a target loss value, or the number of training times reaches a target number of times.
11 . The electronic device according to claim 10 , wherein the to-be-trained three-dimensional volume reconstruction model comprises an enhancement network model and a reconstruction network model;
the enhancement network model is a model based on an encoder-decoder network architecture, and configured to input a DR image group with a perpendicular relationship and output a corresponding training pseudo-sinogram; and
the reconstruction network model is an autoencoder network model for two-dimensional to three-dimensional volume mapping, and configured to input the training pseudo-sinogram and output a corresponding training three-dimensional volume.
12 . The electronic device according to claim 11 , wherein the enhancement network model to input a DR image group with a perpendicular relationship, and output a corresponding training pseudo-sinogram, comprises:
performing pattern and feature extraction on the input DR image group, and performing a cascade operation on a result of the extraction;
performing latent space feature encoding on features after the cascade operation to obtain encoded latent space features; and
decoding the encoded latent space features to obtain the training pseudo-sinogram.
13 . The electronic device according to claim 11 , wherein the reconstruction network model to input the training pseudo-sinogram and output a corresponding training three-dimensional volume, comprises:
performing feature capture and enhancement on the input training pseudo-sinogram;
encoding a result of feature enhancement, and continuously reducing the spatial resolution on the basis of keeping the number of channels unchanged; and
decoding a result of the encoding, and continuously restoring the spatial resolution to a spatial resolution of the reference three-dimensional volume to obtain the training three-dimensional volume.
14 . The electronic device according to claim 10 , wherein the calculating a loss value based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume according to the training order, comprises:
calculating the loss value using a preset loss function based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume,
wherein the preset loss function is a function of a weighted summation of a first loss function and a second loss function; the first loss function is configured to calculate a mean square error loss between a training pseudo-sinogram and a reference pseudo-sinogram, and the second loss function is configured to calculate a mean square error loss of a training three-dimensional volume and a reference three-dimensional volume.
15 . The electronic device according to claim 11 , wherein the calculating a loss value based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume according to the training order, comprises;
calculating the loss value using a preset loss function based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume,
wherein the preset loss function is a function of a weighted summation of a first loss function and a second loss function; the first loss function is configured to calculate a mean square error loss between a training pseudo-sinogram and a reference pseudo-sinogram, and the second loss function is configured to calculate a mean square error loss of a training three-dimensional volume and a reference three-dimensional volume.
16 . The electronic device according to claim 12 , wherein the calculating a loss value based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume according to the training order, comprises:
calculating the loss value using a preset loss function based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume,
wherein the preset loss function is a function of a weighted summation of a first loss function and a second loss function; the first loss function is configured to calculate a mean square error loss between a training pseudo-sinogram and a reference pseudo-sinogram, and the second loss function is configured to calculate a mean square error loss of a training three-dimensional volume and a reference three-dimensional volume.
17 . The electronic device according to claim 13 , wherein the calculating a loss value based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume according to the training order, comprises:
calculating the loss value using a preset loss function based on the training pseudo-sinogram, the training three-dimensional volume, the reference pseudo-sinogram, and the reference three-dimensional volume,
wherein the preset loss function is a function of a weighted summation of a first loss function and a second loss function; the first loss function is configured to calculate a mean square error loss between a training pseudo-sinogram and a reference pseudo-sinogram, and the second loss function is configured to calculate a mean square error loss of a training three-dimensional volume and a reference three-dimensional volume.