System and method for denoising medical images adaptive to local noise

摘要

A system and method is provided for estimating the local noise of CT images and denoising the images using a modified non-local means (NLM) algorithm that is adaptive to local variations of noise levels. A strategy for efficiently estimating the local noise of CT images is also described.

主权项

1. A method for reconstructing a computed tomography (CT) image of a subject, the method comprising:
with a computed tomography (CT) imaging system, acquiring medical imaging data representing the subject that has been irradiated with a dose of radiation and reconstructing a CT image of the subject from said medical imaging data; calculating a raw analytical map of noise in a reconstructed CT image, said raw analytical map having arbitrary scaling; transforming the raw analytical map to a scaled map of noise that matches a spatial noise distribution at a local level of the reconstructed CT image; and forming a noise-reduced reconstructed CT image with the use of a denoising method applied to the reconstructed CT image and said spatial noise distribution at a local level of the reconstructed CT image.