Abstract: A retro-reflector for image-guided operation systems, comprising eight cube corners, wherein the tips of the cube corners are adjacent to each other and each cube corner is formed from three reflective faces, comprising a protection against contamination which prevents dirt from being deposited in the cube corners.

Abstract: The invention relates to a method for visually assisting the alignment of a medical instrument, wherein the instrument is visually displayed on an image output in a positional relationship to a part of a patient's body by means of a medical navigation system, wherein an orientation aid is displayed as a virtual model shape at the instrument or in a particular positioning with respect to a characteristic part of the instrument. It also relates to a planning method for optimized instrument alignment with the aid of such an image assisting method.

Abstract: A method for optimizing the interpretation of analog image signals or sequences of image signals output by medical image recording devices. The correlation of consecutively recorded image signals is tested and, based on the test, the image signals are identified as depicting the same or different images. More specifically, if the correlation is not less than a particular threshold value, it is established that the image signals depict the same image. If the correlation is less than a particular threshold value, it is established that the image signals possibly depict different images. Further, the threshold value is dynamically adjusted if the correlation has changed.

Abstract: The invention relates to a method for calibrating a C-arm x-ray apparatus, comprising the following steps: a) the C-arm x-ray apparatus is moved to an initial position, in particular to an anterior-posterior position; b) a calibration image is produced; c) the position of the centre of projection in the radiation source of the C-arm x-ray apparatus is determined from the information of the calibration image and stored together with associated values for the orbital angle and the polar angle of the arm of the C-arm x-ray apparatus; d) the arm is moved to a number of calibration positions in a range of orbital angles and polar angles, and the relative position of the radiation source and the image intensifier of the C-arm x-ray apparatus is directly measured for each calibration position; e) the change in the position of the radiation source relative to the image intensifier of the C-arm x-ray apparatus is measured for each calibration position; f) the position of the centre of projection which applies to each

Abstract: A system and method for verifying the registration of a fluoroscopy image, wherein an artificial landmark array is introduced into a radiation path of a fluoroscopy apparatus, the landmark array being trackable by a computer assisted, medical navigation system. A fluoroscopy recording is produced with the aid of the fluoroscopy apparatus, and a spatial position of the artificial landmark array at the time the fluoroscopy recording is produced is detected and stored. The fluoroscopy recording is registered onto previously acquired body image data of the navigation system using marking points mapped on the fluoroscopy recording, wherein the marking points are maps of markings on the radiation source. Verification is based on a correspondence between an image shadow of the artificial landmark array on the fluoroscopy recording and a position of the landmark array at the time the recording was produced.

Abstract: Some embodiments discussed relates to an apparatus for holding a substrate, comprising a body with a surface for a semiconductor wafer to rest on, with the surface having a first surface area on which a first area of the semiconductor wafer can rest, and a second surface area on which a second area of the semiconductor wafer can rest, wherein the second surface area protrudes with respect to the first surface area.

Abstract: A marker system and method are provided that can determine a shape and an axial location of a rotationally symmetrical hole in an instrument having a plurality of instrument markers.

Abstract: A marker navigation system for detecting and displaying locations of at least two reference devices, each reference device attachable to a corresponding object includes a detection device for detecting signals emitted from the at least two reference devices, a display device for displaying the locations of the at least two reference devices and/or the objects attached to the at least two reference devices based in accordance with display signals; and a data processing device.

Abstract: A marker navigation system for determining a length of at least one flexible instrument having a first end and a second end, wherein portions of the at least one flexible instrument can be both linear and curved, the marker navigation system includes: a holder for holding the instrument, said holder comprising a first marker device, wherein the second end of the instrument is attached to the holder; a calibrating apparatus including a second marker device and at least one opening for inserting the first end of the instrument, said at least one opening having a predetermined shape and depth; a detection device for detecting a first location of the first marker device and a second location of the second marker device; and a data processing device for determining the length of the instrument.

Abstract: Some embodiments discussed relates to an apparatus for holding a substrate, comprising a body with a surface for a semiconductor wafer to rest on, with the surface having a first surface area on which a first area of the semiconductor wafer can rest, and a second surface area on which a second area of the semiconductor wafer can rest, wherein the second surface area protrudes with respect to the first surface area.

Abstract: Apparatus and method for drying sludge, in particular sewage sludge, by creating a granulate from the dried product. A mixture of a carrier material consisting of recycled sludge which has already been dried and liquid sludge is fed to a dryer 6. The dried product is fed to a solids separator 8 after the dryer 6 and is stored intermediately in the former in an intermediate container that is placed immediately downstream of the separator.

Abstract: A sterile drape for a trackable medical device includes a reinforced film portion and a holding or tensing device. The holding or tensing device is operative to draw the reinforced film portion taut or smooth on or over a surface of the medical device.

Abstract: A method for defining an antetorsion angle ? of a femur is provided. The antetorsion angle ? is defined by two angles ?? and ? that can be determined by means of two images of the femur, wherein the equation tan ?=tan ??/(cos ?·cos ?) can be used to calculate the antetorsion angle ?.

Abstract: A fixing device for securely fixing surgical equipment to a surgical field of a human or animal body includes a first lever element including a first gripping portion and a first handling portion, and a second lever element including a second gripping portion and a second handling portion. The and second lever elements can be connected such that they can be pivoted and detached with respect to each other.

Abstract: A device for fixing a reference element with respect to a field of surgery includes a first fixing portion operable to provide a mechanical resistance against pulling and/or pushing forces, a second fixing portion provided with a surface structure operable to secure the device against an angular force, and a coupling structure. The coupling structure is operative to mechanically couple the second fixing portion to the first fixing portion, wherein said second fixing portion can be pivoted with respect to the first fixing portion.

Abstract: A system and method for identifying the position of the distal end of a bone guide wire is provided. A position and orientation of the proximal end of the guide wire is identified with the aid of a medical, optical tracking and navigation system and a reference device on the proximal end of the guide wire. The orientation of a bone in which the distal end of the guide wire is located is identified with the aid of the medical, optical tracking and navigation system and a reference device on the bone. By means of the ancillary conditions for the course of the guide wire, which are given by the position and orientation of the proximal end and the orientation of the bone, and by taking into account the physical properties of the guide wire, the position of the distal end of the bone guide wire is identified with the assistance of a computer.

Abstract: A system and method for verifying the registration of a fluoroscopy image, wherein an artificial landmark array is introduced into a radiation path of a fluoroscopy apparatus, the landmark array being trackable by a computer assisted, medical navigation system. A fluoroscopy recording is produced with the aid of the fluoroscopy apparatus, and a spatial position of the artificial landmark array at the time the fluoroscopy recording is produced is detected and stored. The fluoroscopy recording is registered onto previously acquired body image data of the navigation system using marking points mapped on the fluoroscopy recording, wherein the marking points are maps of markings on the radiation source. Verification is based on a correspondence between an image shadow of the artificial landmark array on the fluoroscopy recording and a position of the landmark array at the time the recording was produced.

Abstract: A method for optimizing the interpretation of analog image signals or sequences of image signals output by medical image recording devices. The correlation of consecutively recorded image signals is tested and, based on the test, the image signals are identified as depicting the same or different images. More specifically, if the correlation is not less than a particular threshold value, it is established that the image signals depict the same image. If the correlation is less than a particular threshold value, it is established that the image signals possibly depict different images. Further, the threshold value is dynamically adjusted if the correlation has changed.

Abstract: The invention refers to a method for drying sludge, in particular sewage sludge, by creating a granulate from the dried product. According to said method, a mixture of a carrier material consisting of recycled sludge which has already been dried and liquid sludge is fed to a dryer 6. The invention is characterised in that the dried product is fed to a solids separator 8 after the dryer 6 and is stored intermediately in the former in an intermediate container that is placed immediately downstream of said separator. The invention also relates to an installation for carrying out said method.

Abstract: A process and apparatus for mechanical and thermal dewatering of solid-liquid mixture, particularly industrial and sewage sludges, feeds the sludge to a dewatering device to produce a dewatered material which is then dried in a thermal drier. The dewatered sludge is reduced to a granulate-like structure without any intermediate stage and is then dried immediately afterwards. An apparatus for implementing the process includes a mechanical dewatering device being directly connected to a feed unit to produce a granulate-like structure and which is permanently connected to the thermal drier.