摘要:
A method and an apparatus for three-dimensional ultrasound imaging of a needle-like instrument, such as a biopsy needle, inserted in a human body. The instrument is visualized by transmitting ultrasound beams toward the instrument and then detecting the echo signals using a linear array of transducer elements. The problem of ultrasound being reflected from a biopsy needle in a direction away from the transducer array is solved by steering the transmitted ultrasound beams to increase the angle at which the beams impinge upon the biopsy needle. Ideally the ultrasound beams are perpendicular to the biopsy needle. This increases the system's sensitivity to the needle because the reflections from the needle are directed closer to the transducer array. This can be accomplished using either the B mode or the color flow mode of an ultrasound imaging system. The acquired data for multiple two-dimensional image frames is gathered in memory to form a data volume, which is then processed to form a three-dimensional image (by projection) or a two-dimensional slice taken at an angle through the data volume. In particular, a two-dimensional slice which is coplanar with the inserted biopsy needle can be imaged.
摘要:
A three-dimensional projection image representing a projection of a data volume at a predetermined orientation, three cut plane images representing respective mutually orthogonal planar cuts through the data volume, a graphical representation of the data volume at that orientation and graphical representations of the cut planes are displayed in spaced relationship. Each of the cut planes has a respective positional relationship to the data volume graphic that corresponds to the positional relationship of the respective cut plane to the data volume. The graphical representations are displayed in different colors. Any one of the four images can be active in the sense that images are reconstructed in real-time as a trackball is moved. Which of the four images is active is indicated by displaying the corresponding graphical representation in a color denoting the active state.
摘要:
In performing for three-dimensional ultrasound imaging of an object from any angle relative to the plane of acquisition, a human body is scanned to acquire multiple images forming a data volume. The system computer generates a multiplicity of reformatted slices through the data volume and parallel to the imaging plane. For each projected pixel, a ray is cast through the reformatted slices onto the imaging plane. For each pixel along the ray, the accumulated intensity is calculated as a function of the pixel and opacity values for the pixel being processed, the accumulated intensity calculated at the preceding pixel the remaining opacity for the subsequent pixels. The final accumulated intensity for each ray is obtained when the remaining opacity reaches a predetermined minimum. The accumulated intensities for all cast rays form the projected image.
摘要:
A method and an apparatus for allowing the operator of an ultrasound imaging system to switch between two-dimensional slices and three-dimensional projections in such a way that it is easy for the operator to visualize the relationship of the two-dimensional slice to the three-dimensional anatomy. In a "volume rotate" mode, the display screen displays an orientation box along with a three-dimensional projected image generated from a defined data volume. The orientation box provides a visual indication of the shape and orientation of that defined data volume. In a "cut plane" mode, a movable polygon representing a selected two-dimensional slice is displayed inside a stationary orientation box. The polygon provides a visual indication of the orientation and position of the slice relative to the defined data volume. In a "cut plane rotate" mode, a stationary polygon representing a selected two-dimensional slice is displayed inside a rotatable orientation box.
摘要:
A method and apparatus for calculating the inter-slice spacing in a data volume and registering the slices of that volume using SAD calculations. The resulting transformed data volume is then three-dimensionally reconstructed using a projection technique. If during scanning the probe is translated in the Z direction and at the same time is shifted in the X and/or Y direction, the SAD value will be artificially high. By translating two adjacent images with respect to each other in the X direction and then in the Y direction, and searching for the minimum SAD value, the amount of shift in the X and/or Y direction can be determined and that shift can then be removed. Also by rotating two slices with respect to each other and looking for a minimum SAD value, rotational motion of the probe during scanning can be removed.
摘要:
1 method is provided for obtaining an extended field of view diagnostic ultrasound image. A first image frame and a second image frame of an object of interest are acquired. The image frames are rotated relative to one another. Pixel points, representing spatial points in the object of interest, are identified in the first image frame. Pixel points corresponding to the pixel points in the first image frame are then computed in the second image frame. A rotation angle between the first and the second image frames is calculated based on a least-squares relation between the pixel points. The first and second image frames are combined to form a part of an extended field of view image.