Abstract: The invention relates to detection of encephalopathy based on EEG signal data obtained from a patient. A first signal component is derived from the EEG signal data, the first signal component representing low frequencies of the EEG signal data. A first parameter indicative of disorder in the first signal component and a second parameter indicative of disorder in EEG signal data representing a first frequency band are then computed, wherein the first frequency band includes higher frequencies than said low frequencies. An indicator of encephalopathy is then determined based on the first parameter and the second parameter, the indicator of encephalopathy being indicative of encephalopathy.

Abstract: A method and apparatus for ascertaining the cerebral state of a patient. The method/apparatus may find use in ascertaining the depth of anesthesia of the patient. In one embodiment, the entropy of the patient's EEG signal data is determined as an indication of the cerebral state. A frequency domain power spectrum quantity is obtained from the patient's EMG signal data. The latter quantity can be updated more frequently than the EEG entropy due to its higher frequency. The EEG entropy indication and the EMG power spectrum indication can be combined into a composite indicator that provides an immediate indication of changes in the cerebral state of the patient. In another embodiment, the frequency range over which the entropy of the biopotential signal from the patient is determined is broadened to encompass both EEG signal data and EMG signal data and the entropy so determined used as an indication of the patient's cerebral state.

Abstract: A medical X-ray device arrangement for producing three-dimensional information of an object in a medical X-ray imaging, the medical X-ray device arrangement comprising an X-ray source for X-radiating the object from at least two different directions and a detector for detecting the X-radiation to form projection data of the object. The medical X-ray device arrangement comprises means for modelling X-ray attenuation coefficient of said object using a multiresolution representation, eliminating part of the coefficients in said multiresolution representation to form reduced multiresolution representation, and utilizing said projection data in a regularized reconstruction method based on minimizing the penalty F(f)=?Af?m?2/2+??f?B+?g(f) over the coefficients in the said reduced multiresolution representation to produce three-dimensional information of the object.

Abstract: The invention concerns a method for a dentomaxillofacial X-ray imaging. It is provided an X-ray beam (15) having a first radiation spectrum and a flat cross-sectional form towards a predetermined dentomaxillofacial area (Q) of a patient (P), and an image receptor (8) in a carrier (7) positioned outside the head of a patient. During a first exposure said X-ray beam and said carrier with the inserted image receptor are moved in a first rotational or linear direction, whereupon a first image of the dentomaxillofacial area is created on said image receptor. Then it is provided an X-ray beam having a second radiation spectrum and the flat cross-sectional form. During a second exposure said X-ray beam and said carrier with the same image receptor are moved in a second rotational or linear direction that is e.g. opposite to said first direction, whereupon a second image of the same dentomaxillofacial area is created on said image receptor.

Abstract: Arrangement in connection with a patient circuit and an absorber means. The arrangement comprises an information transfer means and an electronic means and a transponder electronically programmed with desired information. The transponder is attached to the absorber means. The information transfer means is arranged to communicate with the transponder, and the electronic means is arranged to carry out desired procedures from the basis of the information obtained from the anaesthesia/ventilation system and via the information transfer means from the transponder attached to the absorber means.

Abstract: A paramagnetic oxygen sensor and method employs a pressure sensor having a membrane extending through an air gap for a magnetic field. A piezoelectric element is mounted on the membrane. Gas chambers are formed on either side of the membrane. The gas mixture, the properties of which are to be measured, is supplied to one of the chambers. A reference gas is applied to the other chamber. A pulsating magnetic field is provided across the air gap and through the chambers containing the gas mixture and reference gas. The differing responses of the gas mixture and reference gas to the magnetic field deflect the membrane. The deflection of the membrane is sensed by the piezoelectric element. The piezoelectric element maybe operated either in a passive mode or active mode to sense the deflection of the membrane.

Abstract: The invention relates to pulse oximeters used to measure blood oxygenation. The current trend towards lower power consumption has brought a problem of erroneous readings caused by intrachannel crosstalk, i.e. errors due to the coupling of undesired capacitive, inductive, or conductive (resistive) pulse power from the emitting side of the pulse oximeter directly to the detecting side of the oximeter. The pulse oximeter of the invention is therefore provided with means for detecting whether intrachannel crosstalk is present and whether it will cause erroneous results in the oxygenation measurements. The pulse oximeter is preferably further provided with means for eliminating intrachannel crosstalk which are adapted to control the measurement so that measurement signals can be obtained which are substantially void of crosstalk components.

Abstract: The present invention concerns a catheter heating circuit for continuous cardiac output measurement. The circuit comprises a DC power source for supplying an operating voltage for the circuit, wherein the heating power from the heating circuit is fed to the catheter via an isolating transformer. Isolation is known per se and it is not described in detail. According to the invention the heating circuit further comprises means for generating a bipolar square wave with variable duty cycle, which square wave is supplied to said isolating transformer and further to the catheter filament.

Abstract: The invention relates to pulsed oximeters used to measure blood oxygenation. The current trend towards mobile oximeters has brought the problem of how to minimize power consumption without compromising on the performance of the device. To tackle this problem, the present invention provides a method for controlling optical power in a pulse oximeter. The signal-to-noise ratio of the received baseband signal is monitored, and the duty cycle of the driving pulses is controlled in dependence on the monitored signal-to-noise ratio, preferably so that the optical power is minimized within the confines of a predetermined lower threshold set for the signal-to-noise ratio. In this way the optical power is made dependent on the perfusion level of the subject, whereby the power can be controlled to a level which does not exceed that needed for the subject.