Analogic Corporation

Basak Ulker Karbeyaz

David Rozas

Doug Q Abraham

Douglas Q Abraham

Charles H Shaughnessy

Carl R Crawford

Sergey Simanovsky

Ram Naidu

Zhengrong Ying

Matthew Waggener Hirsch

David A Schafer

Aleksander Roshi

Steven Neil Urchuk

Anton M Deykoon

Olivier Tousignant

Alexander Zamyatin

Kevin Cheng

Provided are one or more systems and/or techniques for mitigating motion artifacts in a computed tomography image of an anatomical object. Extended scan data is received and includes projections and backprojections acquired for parallel rays emitted by a radiation source at different angular locations within a first range of source angles. The projections and the backprojections are compared to identify differences between the projections and the backprojections at the different angular locations. Movement of the anatomical object during acquisition of the extended scan data at the different angular locations is quantified, and short scan data is identified. The short set includes a subset of the extended scan data acquired at different locations within a second range of source angles where the quantified movement of the anatomical object is less than a movement threshold. The computed tomography image of the anatomical object is reconstructed from the short scan data.

Automated phase selection for ECG-gated cardiac axial CT scans

Among other things, one or more techniques and/or systems are described for processing images yielded from an examination via radiation to reduce visible noise in the images. After an image is reconstructed, a noise contribution to the image (e.g., an amount of noise in the image) is estimated to determine a target noise contribution for the image. The target noise contribution for the image may vary based upon, among other things, dose of radiation, aspects or properties of an object being imaged, etc. The image is subsequently filtered using one or more filtering techniques to generate a filtered image, and a noise contribution to the filtered image is determined. When the noise contribution to the filtered image satisfies the target noise contribution (e.g., a sufficient amount of noise has been filtered out of the image), the filtered image is combined with the reconstructed image to generate a blended image.

Noise reduction in radiation image

Among other things, a tire inspection system and method are provided. A radiation source and a detector array are configured to rotate about an axis of rotation. During a first examination of a tire, the tire has a first orientation relative to the axis of rotation, and during a second examination, the tire has a second orientation relative to the axis of rotation. For example, between the first examination and the second examination, the tire is at least one of shifted with respect to the axis of rotation or rotated about a tire rotation axis (e.g., perpendicular to the axis of rotation) to change the orientation of the tire relative to the axis of rotation. In this manner, imagery of the tire may be developed, which can be inspected to identify irregularities, etc., in the tire, for example.

System and method for tire inspection

Among other things, one or more techniques and/or systems are described for defining imaging modes and for operating a photon counting radiation imaging system. A set of imaging modes with different counting schemes may be defined such that counting schemes will count detection events of a set of radiation events in different manners. For example, a first counting scheme may count primary detection events in a primary counter and secondary detection events in a secondary counter. A second counting scheme may count primary and secondary detection events in the primary counter. A third counting scheme may merely count detection events occurring within a primary detector cell associated with the primary counter. A fourth counting scheme may combine energy of detection events into merged energy. A selected imaging mode may be applied to the photon counting radiation imaging system in order to achieve desired image scanning characteristics (e.g., spatial resolution, dose savings, spectral ability).

Photon counting imaging modes

Among other things, one or more techniques and/or systems are described for resetting an integration circuit () of a detector cell or an electronics arrangement () thereof. When a voltage signal output by the integration circuit () exceeds a specified threshold (e.g., indicating that a specified number of radiation photons have been detected), a charge injection circuit () is configured to inject charge into the integration circuit (). The injected charge is typically opposite in polarity to stored charge that is stored by a capacitor () of the integration circuit () and is configured to counteract the stored charge. In this way, a voltage potential at the capacitor () decreases, causing the voltage signal output by the integration circuit () to decrease. Moreover, a number of resets per measurement interval may be recorded to determine an average current output by a radiation detection element of the detector cell over the measurement interval to facilitate acquiring photon integration readings.

Hybrid photon counting data acquisition system

One or more techniques and/or systems are described for addressing (e.g., during calibration) pixel-by-pixel variations in an image modality that utilizes photon counting techniques, such as by adjusting a number of photons detected by certain pixels (e.g., redistributing or reallocating detected photons among pixels). Such variations may cause an effective area of one or more pixels of a detector array to be larger than the effective area of other pixels, resulting in more photons being counted by some pixels than others, which can degrade resulting images. Accordingly, photons are redistributed as provided herein so that, when exposed to substantially uniform radiation, photon counts of neighboring pixels are substantially equal, statistical noise among neighboring pixels is substantially equal, and a signal-to-noise ratio among neighboring pixels is substantially equal. By redistributing photons as described herein, a spatial uniformity and/or a modulated transfer function (MTF) associated with a detector array may be improved.

Photon count correction

Among other things, one or more techniques and/or systems for counting detection events via a photon counting detector array is provided. A first instance where an amplitude of an electrical signal exceeds an event threshold is detected. The first instance is generated responsive to a first detection event at a detector cell. An event counter is disabled from counting other detection events at the detector cell for a first blocking interval. At a conclusion of the first blocking interval, the amplitude of the electrical signal is determined. Responsive to determining that the amplitude of the electrical signal is below the event threshold, an adjustment is made to an event count based upon the first detection event. Responsive to determining that the amplitude of the electrical signal exceeds the event threshold, the event counter is disabled from counting other detection events at the detector cell for a second blocking interval.

Photon counting system and method

Among other things, one or more techniques and/or systems are described for counting detection events on a detector cell of a photon counting detector array. An electronics arrangement of the detector cell comprises a digital discriminator which is configured according to an impulse response of the detector cell or, more particularly, an impulse response of a radiation detection element of the detector cell (e.g., where the radiation detection element is configured to convert energy of the radiation photon into electrical charge). The digital discriminator is configured to analyze a digital representation of a voltage signal of the detector cell and to compare a result of the analysis to one or more metrics derived based upon the impulse response of the detector cell to identify voltage pulses of the voltage signal that are indicative of detection events.

Noise discrimination in photon counting system

A method and system are provided for generating high resolution CT images. The NSR# method improves on the AMPR method, by increasing the in-plane image resolution of CT scanners, in the helical scanning mode. The provided method uses the quarter detector offset and interleaving of complementary data to achieve in plane image resolution that is similar to the high resolution axial scanning mode utilizing quarter detector offset and interleaving. The method includes several ways of choosing the data to be interleaved, like NSR# with two planes, NSR# with 3 planes, NSR# with multiple planes. The interleaved data are used to create high resolution tilted slices. The NSR# method optimizes the untilting filter to create a mix of high and low resolution tilted slices to achieve the desired in-plane image resolution-image artifact balance required for the imaging task. In one embodiment in the untilting process one may use only high resolution tilted slices, for maximum resolution benefit. In another embodiment one may mix high resolution tilted slices with standard resolution tilted slices resulting from data that did not go through interleaving. This creates unfilled slices of higher resolution than the standard and with lower artifacts. In another embodiment for scans with pitch lower than &#x2154; one may reduce the collimation to reduce the dose to the patient.

Method and system for high resolution nutated slice reconstruction using quarter detector offset

A method of and a system for variable pitch CT scanning for baggage screening and variable pitch image reconstruction are disclosed. The method comprises decelerating conveyor belt speed when additional time is needed to render a decision on a complex bag; accelerating conveyor belt speed to its normal speed when decisions are reached on undecided bags; generating cone-beam projection data at variable scanning pitch corresponding to variable conveyor belt speed; computing a tilt angle and a distance offset for each tilted slice using the pitch values at which the cone-beam projection data is acquired for that tilted slice; generating fan-beam projection data for each tilted slice using the tilted angle and the distance offset; generating correction projection data to compensate for the error between the source trajectory and the tilted reconstruction plane; generating the corrected fan-beam projection data by adding the correction projection data to the fan-beam projection data; reconstructing tilted slices using the corrected fan-beam projection data; and interpolating the reconstructed tilted slices into axial slices.

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Concord, MA, United States of America

Basak Ulker Karbeyaz