39 results about "Virtual CT colonoscopy" patented technology

A system and method for generating a three-dimensional visualization image of an object such as an organ using volume visualization techniques and exploring the image using a guided navigation system which allows the operator to travel along a flight path and to adjust the view to a particular portion of the image of interest in order, for example, to identify polyps, cysts or other abnormal features in the visualized organ. An electronic biopsy can also be performed on an identified growth or mass in the visualized object. Virtual colonoscopy can be enhanced by electronically removing residual stool, fluid and non-colonic tissue from the image of the colon, by employing bowel preparation followed by image segmentation operations. Methods are also employed for virtually expanding regions of colon collapse using image segmentation results.

A system for performing a virtual colonoscopy includes a system for generating digital images, a storage device for storing the digital images, a digital bowel subtraction processor coupled to receive images of a colon from the storage device and for removing the contents of the colon from the image and an automated polyp detection processor coupled to receive images of a colon from the storage device and for detecting polyps in the colon image.

A method for automatic local path planning for a virtual endoscope comprises the steps of defining a sub volume around a current endoscope position in a lumen; performing a region growing inside the lumen, starting from the current endoscope position; calculating and clustering the intersection of the region with the faces of a cube circumscribing the sub volume; calculating approximated centerline paths from the current endoscope position to the center of each cluster formed in the preceding step; comparing each of the centerline paths with a current path exhibited by the endoscope; and selecting an optimal centerline path based on the comparison.

A method for automatically determining a start or finish location near to an end of a lumen in a medical image data set is described. The location may thus be used in determining a camera path for virtual endoscopy (e.g. colonoscopy). The data set comprises a plurality of voxels arranged along first, second and third directions and the method includes: segmenting the data set to identity a group of voxels classified as belonging to the lumen; selecting one of the axes of the data set as a primary direction based on an expected direction of the lumen at the end of interest; selecting a slice through the data set which is perpendicular to the primary direction and includes voxels at a spatial extremity of the group of voxels classified as belonging to the lumen along this direction; identifying a two-dimensional (2D) region of the voxels classified as belonging to the lumen within the selected slice; and selecting, based on the position of the 2D region, a position within the data set as the terminal location for the virtual colonoscopy camera path.

An apparatus and method are provided for use in administering a rectal contrast enema to a patient to prepare the patient for a medical procedure. A rectal catheter may be provided to facilitate administration of the enema preparation to the patient. The rectal catheter may include a retention balloon. A delivery mechanism may be provided to urge the enema preparation into the patient. A vacuum may be provided to remove waste from the patient. A gas insufflator may be provided to insufflate the patient's colon for a medical procedure such as a scan, and more specifically, a virtual colonoscopy.

A system, method, software arrangement and computer-accessible medium for performing electronic cleansing of CT colonography images are provided. In this system, method, software arrangement and computer-accessible medium, the digital bowel cleansing can be performed to remove tagged bowel contents from the images. The digital bowel cleansing can apply a local shape analysis throughout the images and use a shape-based speed function to detect the folds and polyps structures while removing the tagged bowel contents region. The system, method, software arrangement and computer-accessible medium can enable a medical examiner to perform an accurate virtual colonoscopy on a patient, without the need for thorough patient preparation.

A method for automatic virtual endoscopy navigation, including: (a) using a fisheye camera to generate an endoscopic image and a depth image from a current position of the camera in lumen computed tomographic (CT) data; (b) segmenting a first region and a second region from the depth image, wherein the first region identifies a view direction of the camera and the second region is an area through which the camera can be moved without touching an inner surface of the lumen; (c) moving the camera from the current position, while pointing the camera in the view direction, to a next position in the second region; and (d) repeating steps (a-c) in sequence using the next position in step (c) as the current position in step (a).

The present invention provides agents and methods for dual modality virtual colonoscopy that gives both anatomical and functional information using hybrid CT/PET scanning. In preferred embodiments, the present invention provides radiolabeled tumor-specific agents and methods for distinguishing benign polyps from malignant tumors. In further embodiments, the present invention provides compositions and methods useful for distinguishing morphological and functional subregions of a selected region of tissue based on relative levels of phospholipid metabolism. Preferred radiolabeled tumor-specific agents are phospholipid ether analogs labeled with a halogen radiosiotope. In certain preferred embodiments, the compositions including radiolabeled phospholipid ether analogs have therapeutic actions in addition to functionally identifying malignant tissue.

Various techniques can be used to improve classification of colon polyps candidates found via computed tomographic colonography computer aided detection (CTCCAD). A polyp candidate can be classified as a true positive or a false positive. For example, a two-dimensional projection image of the polyp can be generated from a three-dimensional representation and classified based on features of the projection image. An optimal viewpoint for the projection image can be found via techniques such as maximizing viewpoint entropy. Wavelet processing can be used to extract features from the two-dimensional projection image. Feature extraction can use a piecewise linear orthonormal floating search for locating most predictive neighbors for wavelet coefficients, and support vector machines can be employed for classification. The techniques can be useful for improving accuracy of CTCCAD techniques.

The invention provides a full-automatic segmentation method for a mixed tissue image of a simulated colonoscopy, comprising the following steps of: selecting a suitable threshold value of the air and of the enteral residual liquid; carrying out an initial segmentation for the enteral area through a traditional threshold method; wiping a local volume effect between the air and the enteral residual liquid through a vertical filter; conducting an enteral segmentation through a region growing method; enhancing the boundaries of the colon and other issues through a gradient intensity region growing method; repeating a wiping of the local volume effect between the air and the enteral residual liquid through the vertical filter for the inner part of the colon with enhanced boundaries. The full-automatic segmentation method for the mixed tissue image of a simulated colonoscopy overcomes the problems of the traditional threshold segmentation, eliminates the impacts from the local volume effect, and renders the segmentation results better in conformity with the actual conditions.

Methods and apparatus for improving a virtual colonoscopy and a CT angiography. Embodiments of the present invention provide a contrast media into the patient's stool or blood stream so as to reduce an attenuation signal of the patient's stool or blood. Reducing the signal of the stool allows an examining physician to better differentiate the stool from polyps in the colon and allows an examining physician to better differentiate the blood from an arterial wall.

A method for automatic local path planning for a virtual endoscope comprises the steps of defining a sub volume around a current endoscope position in a lumen; performing a region growing inside the lumen, starting from the current endoscope position; calculating and clustering the intersection of the region with the faces of a cube circumscribing the sub volume; calculating approximated centerline paths from the current endoscope position to the center of each cluster formed in the preceding step; comparing each of the centerline paths with a current path exhibited by the endoscope; and selecting an optimal centerline path based on the comparison.

The instant invention combines three distinct components to form a single effective bowel preparation for virtual colonoscopy (VC) examination: 4) a cathartic for colonic cleansing; 5) barium sulfate for stool tagging; and 6) water soluble iodinated contrast for colonic fluid opacification. Each component has been employed previously for VC preparation with sub-optimal results. The unique bowel preparation described herein combines these components and has been proven highly effective in a large, prospective multi-center VC screening trial. In addition to being highly efficient, the packaging of these three components into a single preparation kit is much more convenient for patients and their referring physicians. The specific timing and dosage of each component can vary within an acceptable effective range.

A computer-assisted method for detecting surface features in a virtual colonoscopy. The method includes providing a three-dimensional construction of a computed tomography colonography surface; creating a path along the teniae coli from the proximal ascending colon to the distal descending colon on the colonography surface; forming an indexed computed tomography colonography surface using the created path; and registering the supine and prone scans of the computed tomography colonography surface using the indexed computed tomography colonography surface. The method also includes navigating the internal surface of the computed tomography colonography using the indexed computed tomography colonography surface.

A method and a device are disclosed for providing a segmented volume data record for a virtual colonoscopy, the volume data record having image information relating to the intestines of a creature, which intestines have been labeled by a first and a second contrast agent. In at least one embodiment, voxels representing the first contrast agent, voxels representing stool remains labeled by the second contrast agent and voxels representing intestinal tissue are segmented, the segmentation taking place in a volume data record recorded of the body region of the creature having the intestines, which have been labeled by a first and a second contrast agent. In at least one embodiment, at least sections of the intestinal wall are displayed on the basis of the segmentation in the virtual colonoscopy, even if these sections of the intestinal wall are, in the segmented volume data record, covered by stool remains labeled by the second contrast agent. Further, a computer program product having a computational program for carrying out the method is also disclosed.

A visualizing method based on virtual colonoscope includes such steps as obtaining the fly path of virtual navigation by manually or automatically generating the path, combining the manual navigation with automatic navigation, on the basis of automatic navigation stopping the automatic fly at any time to get the control right to virtual lens for carefully observing the target region in any direction, and activating the automatic fly again. Its advantages are high freedom and high diagnosing reliabiligy.

A method for filtering image data having at least three types of distinct regions from a selected type of region, each of the at least three types of distinct regions being characterized by a plurality of unitary image elements, the method comprising providing the image data; selecting a portion of the image data comprising at least a corresponding portion of each of the at least three types of regions; determining at least one distribution for each of the at least three types of regions in the selected portion; determining at least one function for associating each unitary image element of the selected type of region in the selected portion to another type of region of the at least three types of regions such that the at least one distribution of the selected type of regions in the selected portion is transposed into a corresponding distribution of the another type of region; and applying the at least one function to each unitary image element of the selected type of region of the selected portion to thereby provide filtered image data. Applications of the method for suppressing tagged material in virtual colonoscopy are also disclosed.