摘要:
A method for segmenting at least a pair of regions of an image. High resolution data is obtained of the image. Each one of the pair of the regions in the image is marked. Graph cuts are used on the downsampled data to obtain first voxels along an outer boundary of a selected one of the pair of marked regions and second voxels along an inner boundary the selected region. The graphs cuts are projected to the previously obtained high-resolution image data. First and second sets of seeds are placed on the first voxels and a second set of seeds respectively. The first seeds grow into first areas extending inwardly of the selected region while simultaneously the second seeds grow into second areas extending towards the first extending areas until the first areas and the second areas meet to thereby establish the outer boundary of the selected region.
摘要:
A method and system for non-rigidly registering a fixed to a moving image utilizing a B-Spline based free form deformation (FFD) model is disclosed. The methodology utilizes sparse feature correspondences to estimate an elastic deformation field in a closed form. In a multi-resolution manner, the method is able to recover small to large non-rigid deformations. The resulting deformation field is globally smooth and guarantees one-to-one mapping between the images being registered. The method generally comprises the steps of: detecting feature points on the fixed image and feature points on the moving image; assigning a feature vector to each feature point; calculating the dissimilarity of each pair of feature vectors for feature pairs on the fixed image and the moving image; calculating the correspondence between feature pairs based on the dissimilarity measure; solving for a dense deformation field P using a closed form FFD model; and transforming the moving image and the feature points on the moving image using a current FFD deformation field estimate.
摘要:
A method for three-dimensional reconstruction of a branched object from a rotational sequence of images of the branched object includes segmenting the branched object from each image of the sequence, extracting centerlines of the branched object, performing symbolic reconstruction via a stereo correspondence matching between the centerlines from different views of the sequence of images using a graph cut-based optimization, and creating a three-dimensional tomographic reconstruction of the branched object compensated for motion of the branched object between the images of the sequence.
摘要:
A method of aligning a pair of images includes providing a pair of images with a first image and a second image, wherein the images comprise a plurality of intensities corresponding to a domain of points in a D-dimensional space. Salient feature regions are identified in both the first image and the second image, a correspondence between each pair of salient feature regions is hypothesized, wherein a first region of each pair is on the first image and a second region of each pair is on the second image, the likelihood of the hypothesized correspondence of each pair of feature regions is measured, and a joint correspondence is determined from a set of pairs of feature regions with the greatest likelihood of correspondence.
摘要:
A multilevel image segmentation technique using graph cuts is disclosed. A reduced resolution image is generated from a full resolution image which is to be segmented. The reduced resolution image is then segmented in order to identify a boundary between an object and a background within the image. The identified boundary then identifies a portion of an increased resolution image which is segmented in order to refine the earlier identified boundary. The steps may be iterated for successively increasing image resolutions in order to refine the boundary as required by a particular application. An initial identification of object and background portions of the image may be provided as input by a user. Alternatively, a user may identify only the object portion, and the background portion may be automatically determined.
摘要:
A fluoroscopy image is registered with data representing a volume, identifying a catheter position relative to a volume represented by preoperative volume data. The catheter position relative to a patient volume represented by data acquired without scanning the catheter is displayed. For example, a 2D fluoroscopy image is registered with respect to coordinates of a 3D preoperative CT or MRI volume by registering the fluoroscopy image and the preoperative volume to 3D ultrasound coordinates.
摘要:
A method for registering images of multiple modalities includes acquiring first image of a subject using a first modality. A second image of the subject is acquired using a second modality. The first image includes greater structural detail of the subject than the second image and the second image is a video image including multiple image frames. The first and second images are registered based on an anatomical structure observable in the first image and a foreign object proximate to the anatomical structure observable in the second image.
摘要:
A human cavity inner wall three-dimensional mapping method, and a corresponding device and system, comprising: at least one field generating device which generates a plurality of distinguishable fields under excitation of a drive signal; at least one field sensor located in a target device for detecting the distinguishable fields to generate a sensor signal; and a positioning signal processing device for transmitting the drive signal to the field generating device and detecting the output of the field sensor signal to acquire data of five-dimensional position and orientation coordinates of a position on the target device where the sensor is located.
摘要:
A method of registering 3-dimensional digitized images to 2-dimensional digitized images during a medical procedure includes providing a pair of correctly-registered training images L={lr, lf} and their joint intensity distribution pl(ir, if), wherein ir and if are reference and floating images, respectively, providing a pair of observed images O={or, of} and their joint intensity distribution po(ir, if), mapping a marginal intensity distribution of the observed pair O={or, of} to a marginal intensity distribution of the training pair L={lr, lf}, and estimating a set of parameters T that registers image of to image or by maximizing a weighted sum of a Jensen-Shannon divergence (JSD) of a joint intensity distribution of the observed pair and a joint intensity distribution of the training pair and a similarity measure between the observed images.
摘要:
A method for registering images of multiple modalities includes acquiring first image of a subject using a first modality. A second image of the subject is acquired using a second modality. The first image includes greater structural detail of the subject than the second image and the second image is a video image including multiple image frames. The first and second images are registered based on an anatomical structure observable in the first image and a foreign object proximate to the anatomical structure observable in the second image.