摘要:
A method for automated detection of abnormal anatomic regions, wherein a mammogram is digitized to produce a digital image and the digital image is processed using local edge gradient analysis and linear pattern analysis in addition to feature extraction routines to identify abnormal anatomic regions. Noise reduction filtering and pit-filling/spike-removal filtering techniques are also provided. Multiple difference imaging techniques are also used in which difference images employing different filter characteristics are obtained and processing results logically OR'ed to identify abnormal anatomic regions. In another embodiment the processing results with and without noise reduction filtering are logically AND'ed to improve detection sensitivity. Also, in another embodiment the wavelet transform is utilized in the identification and detection of abnormal regions. The wavelet transform is preferably used in conjunction with the difference imaging technique with the results of the two techniques being logically OR'ed.
摘要:
A method and system for the detection of microcalcifications in digital mammograms. Digital mammograms are obtained and regions-of-interest (ROIs) are selected therefrom which contain suspected microcalcifications, either individual or clustered microcalcifications. The suspect ROIs are background-trend corrected, followed by Fourier transformation and power spectrum calculation to perform detection in the frequency domain. Detection can also be carried out in the spatial domain by omitting the Fourier transformation and power spectrum calculation. The ROI is then scaled for input into a neural network trained to detect microcalcifications. The neural network outputs ROIs with detected microcalcifications. The method and system can also include normalizing the background-trend corrected ROIs and imputing the normalized ROI to a shift-invariant neural network trained to detect microcalcifications. The output ROI of the shift-invariant neural network is thresholded to remove additional false positive detections, and then the thresholded ROI undergoes a cluster detection to detect clustered microcalcifications. Feature extraction techniques can be applied to the remaining ROI to remove additional false positive detections.
摘要:
A method and system for computer-aided differential diagnosis of diseases, and in particular, computer-aided differential diagnosis using neural networks. A first embodiment of the neural network distinguishes between a plurality of interstitial lung diseases on the basis of inputted clinical parameters and radiographic information. A second embodiment distinguishes between malignant and benign mammographic cases based upon similar inputted clinical and radiographic information. The neural networks were first trained using a hypothetical data base made up of hypothetical cases for each of the interstitial lung diseases and for malignant and benign cases. The performance of the neural network was evaluated using receiver operating characteristics (ROC) analysis. The decision performance of the neural network was compared to experienced radiologists and achieved a high performance comparable to that of the experienced radiologists. The neural network according to the invention can be made up of a single network or a plurality of successive or parallel networks. The neural network according to the invention can also be interfaced to a computer which provides computerized automated lung texture analysis to supply radiographic input data in an objective and automated manner.
摘要:
A computerized scheme for the analysis of digitized medical images which provides enhancement of interval changes occurring in a pair of temporally sequential images. In the method and apparatus of the invention, a pair of images are digitized and then are subjected to image registration including a nonlinear warping of one of the images so that corresponding locations in the two images are aligned with each other. Subsequent to image registration, a subtraction process is performed in order to generate a difference between the warped and unwarped images. In this manner, slight opacities which are only present in the later image may be detected based on the subtraction of the registered images.
摘要:
An optical image processing method and system in a radiographic system, wherein an image of an object is produced by an image intensifier and converted to video signal by a television (TV) camera system. A liquid crystal display (LCD) is placed bewteen the image intensifier and the T.V. camera system at a location shifted from a focal plane of the T.V. camera system. The liquid crystal display defines plural pixels which are controllable so that light produced by the image intensifier and impinging on the plural LCD pixels can be selectively attenuated by application of selected control signals to the LCD. Control signals are generated selectively based on predetermined parameters of the radiographic system and the image. These control signals are applied to the LCD to perform selective attenuation and corresponding dynamic range compression of light passing through respective LCD pixels, thereby to perform unsharp masking of the image produced by the image intensifier using the LCD.
摘要:
A method and system for reconstructing image data obtained from plural sequential exposures of an object by a radiation source through a multiple slit beam scanning assembly, wherein frames of original image data in the form of plural pixels are obtained for each discrete scanning step/exposure and a minimum pixel value of at least one frame is determined. Based on this determined minimum value, a cutoff value is determined. The pixel values of each frame are compared with the cutoff value, and the image is reconstructed by summation of all the pixel image data above the cutoff value for each respective pixel. In order to improve spatial resolution, the slit width of the scanning assembly is selected be the narrower than the pixel size. Pixel image data produced by exposure from radiation passing through the same slit of the scanning assembly in consecutive scanning steps are then assigned to adjacent pixels in a direction perpendicular to the scanning beam of an enlarged pixel matrix. To achieve a balanced aspect ratio, pixel values for pixels in a direction parallel to the scanning beam are assigned by interpolation between pixel values assigned in the perpendicular direction.
摘要:
A method, system, and computer program product for modifying an appearance of an anatomical structure in a medical image, e.g., rib suppression in a chest radiograph. The method includes: acquiring, using a first imaging modality, a first medical image that includes the anatomical structure; applying the first medical image to a trained image processing device to obtain a second medical image, corresponding to the first medical image, in which the appearance of the anatomical structure is modified; and outputting the second medical image. Further, the image processing device is trained using plural teacher images obtained from a second imaging modality that is different from the first imaging modality. In one embodiment, the method also includes processing the first medical image to obtain plural processed images, wherein each of the plural processed images has a corresponding image resolution; applying the plural processed images to respective multi-training artificial neural networks (MTANNs) to obtain plural output images, wherein each MTANN is trained to detect the anatomical structure at one of the corresponding image resolutions; and combining the plural output images to obtain a second medical image in which the appearance of the anatomical structure is enhanced.
摘要:
A method of producing an image to aid detection of a change in progress of a disease in a patient is described. In the method, a first image of a distribution of a radioisotope in the patient is obtained. A second image of the distribution of the radioisotope in the patient is also obtained. At least one of the first and second images are then normalized (1:140). One of the images is warped to match the other image using a multiple-segment matching method (1:160). The first image is subtracted from the second image to form a subtraction image (1:220). Finally, the resulting subtraction image is displayed.
摘要:
A method, system, and computer program product for modifying an appearance of an anatomical structure in a medical image, e.g., rib suppression in a chest radiograph. The method includes: acquiring, using a first imaging modality, a first medical image that includes the anatomical structure; applying the first medical image to a trained image processing device to obtain a second medical image, corresponding to the first medical image, in which the appearance of the anatomical structure is modified; and outputting the second medical image. Further, the image processing device is trained using plural teacher images obtained from a second imaging modality that is different from the first imaging modality. In one embodiment, the method also includes processing the first medical image to obtain plural processed images, wherein each of the plural processed images has a corresponding image resolution; applying the plural processed images to respective multi-training artificial neural networks (MTANNs) to obtain plural output images, wherein each MTANN is trained to detect the anatomical structure at one of the corresponding image resolutions; and combining the plural output images to obtain a second medical image in which the appearance of the anatomical structure is enhanced.
摘要:
An automated computerized scheme for determination of the likelihood of malignancy in pulmonary nodules. The present invention includes steps of obtaining at least one computed tomography medical image of a pulmonary nodule in determining if the pulmonary nodule is malignant based on the examination of seven patient or image features. The method can be implemented when instructions are loaded into a computer to program the computer. The significance of employing seven patient or image features is that statistically, seven features are the most practical based on the unique implementation of statistical analysis. Out of the seven features that are now analyzed to determine if a pulmonary nodule is malignant, these features are selected to optimize the accuracy of the diagnosis of a pulmonary nodule. Through a unique sampling scheme, different embodiments of the present invention utilize different combinations of features to optimize the accuracy of the method of the present invention.