Method for helical windmill artifact reduction with noise restoration for helical multislice CT

A system for processing a medical image, comprising:

• an apparatus configured to obtain a first plurality of images, the first plurality of images collectively defining a first image volume;
• a processor configured to (1) filter the first plurality of images to create a second plurality of images, each image in the second plurality of images comprising an average of at least two images in the first plurality of images, wherein each image in the first plurality of images is a thin image, and each image in the second plurality of images is a thick image;
• (2) select a first thin image from the first plurality of images;
• (3) add a lost noise image to a second thick image in the second plurality of images to create a noise restored image, the second thick image in the second plurality of images corresponding to the first thin image in the first plurality of images;
• (4) determine a gradient image based on pixel values in the second plurality of images, the gradient image comprising a gradient value at each pixel location in the second thick image;
• and (5) combine, based on the determined gradient image, the first thin image and the noise restored image to obtain a corrected image in which an appearance of an imaging artifact is reduced.

A system for processing a medical image, comprising:

• a memory configured to store a first plurality of images, the first plurality of images collectively defining an image volume;
• a filtering mechanism configured to filter the first plurality of images to create a second plurality of images, each image in the second plurality of images comprising an average of at least two images in the first plurality of images, wherein each image in the first plurality of images is a thin image, and each image in the second plurality of images is a thick image;
• a selecting mechanism configured to select a first thin image from the first plurality of images;
• an adding mechanism configured to add a lost noise image to a second thick image in the second plurality of images to create a noise restored image, the second thick image in the second plurality of images corresponding to the first thin image in the first plurality of images;
• a determining mechanism configured to determine a gradient image based on pixel values in the second plurality of images, the gradient image comprising a gradient value at each pixel location in the second thick image;
• and
• a combining mechanism configured to combine, based on the determined gradient image, the first thin image and the noise restored image to obtain a corrected image in which an appearance of an imaging artifact is reduced.

A computer readable medium storing program instructions for execution on a computer system, which when executed by the computer system, cause the computer system to process a medical image by performing the steps of:

• obtaining a first plurality of images, the first plurality of images collectively defining a first image volume;
• filtering the first plurality of images to create a second plurality of images, each image in the second plurality of images comprising an average of at least two images in the first plurality of images, wherein each image in the first plurality of images is a thin image, and each image in the second plurality of images is a thick image;
• selecting a first thin image from the first plurality of images;
• adding a lost noise image to a second thick image in the second plurality of images to create a noise restored image, the second thick image in the second plurality of images corresponding to the first thin image in the first plurality of images;
• determining a gradient image based on pixel values in the second plurality of images, the gradient image comprising a gradient value at each pixel location in the second thick image;
• and
• combining, based on the determined gradient image, the first thin image and the noise restored image to obtain a corrected image in which an appearance of an imaging artifact is reduced.