An image guided catheter navigation system for navigating a region of a patient includes an imaging device, a tracking device, a controller, and a display. The imaging device generates images of the region of the patient. The tracking device tracks the location of the catheter in the region of the patient. The controller superimposes an icon representing the catheter onto the images generated from the imaging device based upon the location of the catheter. The display displays the image of the region with the catheter superimposed onto the image at the current location of the catheter.

Navigation system for cardiac therapies

Digital x-ray tomosynthesis is a technique for producing slice images using conventional x-ray systems. It is a refinement of conventional geometric tomography, which has been known since the 1930s. In conventional geometric tomography, the x-ray tube and image receptor move in synchrony on opposite sides of the patient to produce a plane of structures in sharp focus at the plane containing the fulcrum of the motion; all other structures above and below the fulcrum plane are blurred and thus less visible in the resulting image. Tomosynthesis improves upon conventional geometric tomography in that it allows an arbitrary number of in-focus planes to be generated retrospectively from a sequence of projection radiographs that are acquired during a single motion of the x-ray tube. By shifting and adding these projection radiographs, specific planes may be reconstructed. This topical review describes the various reconstruction algorithms used to produce tomosynthesis images, as well as approaches used to minimize the residual blur from out-of-plane structures. Historical background and mathematical details are given for the various approaches described. Approaches for optimizing the tomosynthesis image are given. Applications of tomosynthesis to various clinical tasks, including angiography, chest imaging, mammography, dental imaging and orthopaedic imaging, are also described.

https://iopscience.iop.org/article/10.1088/0031-9155/48/19/R01/pdf

Digital x-ray tomosynthesis: current state of the art and clinical potential

A surgical navigation system for navigating a region of a patient includes a non-invasive dynamic reference frame and/or fiducial marker, sensor tipped instruments, and isolator circuits. The dynamic reference frame may be repeatably placed on the patient in a precise location for guiding the instruments. The instruments may be precisely guided by positioning sensors near moveable portions of the instruments. Electrical sources may be electrically isolated from the patient.

Method and apparatus for surgical navigation

A stereotactic navigation system for navigating an instrument to a target within a patient may include a stereotactic head frame, an imaging device, a tracking device, a controller and a display. The stereotactic head frame is coupled to the patient and is used to assist in guiding the instrument to the target. The imaging device captures image data of the patient and of the stereotactic head frame. The tracking device is used to track the position of the instrument relative to the stereotactic head frame. The controller receives the image data from the imaging device and identifies the stereotactic head frame in the image data and automatically registers the image data with navigable patient space upon identifying the stereotactic head frame, while the display displays the image data.

Method and apparatus for performing stereotactic surgery

Methods and apparatus for identifying an eye, especially a human eye (10), on the basis of the visible features of the iris (20) and pupil (30). The eye is first illuminated until the pupil reaches a predetermined size, at which an image of the iris and pupil is obtained. This image is then compared with stored image information for identification. The stored image information is previously obtained from an eye, the pupil of which was similarly brought to the same predetermined size. The illumination of the iris may include oblique illumination from several positions around the circumference of the iris. The illumination from each position may be relatively monochromatic, so that the resulting shadow will lack the color of the light source (172) at that position providing better contrast for elevation-dependent features. A system for performing iris recognition (100) may include a processor (190) which controls an illumination control circuit (170) and a camera (180) to obtain images at several predetermined sizes of the pupil.

Iris recognition system.

A method and arrangement for tomographic synthetic image formation involve passing light through the object (6) from several positions to form perspective images (11) on a recording medium (10). The images are smapled by placing a lens at the source positions so as to superimpose them on a light sensitive layer, thus recording the visual image. The arrangement is designed to produce a natural locking image without defects. The perspective image is partially overlayed by a blurred image derived from the perspective image and of an intensity corresp. to that of the defect present in the image. The blurred image may be conducted by superimposing several visual images lying in front of and/or behind the layer image. This may involve moving the recording medium, lens and/or light sensitive film along the optical system axis.

Synthetic formation of defect-free images - by superimposed blurring images of defect on reconstituted multiple perspective images

So far, three-dimensional X-ray imaging methods like tomography, etc. require exposure times of a few seconds or more. Hence, moving objects like the pulsating heart cannot be observed. This obstacle can be overcome by using an array of synchronously flashed X-ray sources. The source array acts as the coded aperture. The X-ray photograph is decoded optically, showing arbitrary layers of the object. We present four new versions of ‘flashing tomosynthesis’, as this approach is called. The obtainable image qualities and other practical features of these four new methods will be compared.

Coded Aperture Imaging with X-rays (Flashing Tomosynthesis)

Three-dimensional coded aperture imaging using nonredundant point distributions

In third generation computer tomography apparatus, wherein radiation behind the object is measured by means of a large number of detection elements, a detection device comprises a number of detection elements which is larger than necessary for the measurement of the fan-shaped radiation beam, per se, in a direction parallel to the axis of rotation. Means are included for displacing the detection device in the direction of the axis of rotation. Detector element unbalance effects are thus averaged.

Device for measuring the absorption of radiation in a slice of a body

Method of spatially decoding the three dimensional interference pattern image e.g. X-ray, holographic application uses several light sources. The coded image is decoded using a matrix with co-ordinates aligned for the various light sources. The advantage is the simplicity with which the equipment can be set up and used as it is basically a light box equipment. Several light sources (3, 3', 3") in a light box (2) are used to expose the object (4) by flash and produce an image on the film (5). Reversal of the geometry is used to view the image.

Hermann Weiss

Papers

Synthetic formation of defect-free images - by superimposed blurring images of defect on reconstituted multiple perspective images

Coded Aperture Imaging with X-rays (Flashing Tomosynthesis)

Three-dimensional coded aperture imaging using nonredundant point distributions

Device for measuring the absorption of radiation in a slice of a body

System decoding superimposed images - uses several light sources and matrix to decode primary images etc. by spatial displacement