What is a sinogram in CT?
In CT and SPECT imaging, a sinogram is generated by rotating detectors around a patient, and storing the detected projection profiles at each angle in the sinogram, as depicted in the gif above.
What is CT reconstruction?
Image reconstruction in CT is a mathematical process that generates tomographic images from X-ray projection data acquired at many different angles around the patient. Image reconstruction has fundamental impacts on image quality and therefore on radiation dose.
What is projection in CT scan?
CT makes use of filtered back projection reconstruction techniques, whereby each projection is convolved with a “filter”, and then back projected. When this procedure is performed for all 1000 or so projections, it is possible to achieve a perfect reconstruction of the scanned object.
What does a sinogram represent?
The 2D Radon transform is usually graphically represented as a sinogram, which means the intensity values in the coordinate system of variables .
What is sinogram in image processing?
A sinogram is a 2D representation of an X-ray CT scan, where each column represents a single row in the projection image arranged in increasing angular order. Typically, the horizontal axis represents the angle of the X-ray detector and the vertical axis, the distance from the rotation center in the detector row.
What is a sinogram imaging?
A sinogram is a special x-ray procedure that is done to visualize any abnormal opening (sinus) in the body, following the injection of contrast media (x-ray dye) into the opening.
What is kernel in CT?
The kernel, also known as a convolution algorithm, refers to the process used to modify the frequency contents of projection data prior to back projection during image reconstruction in a CT scanner 1. This process corrects the image by reducing blurring 1.
What is FBP reconstruction?
Filtered back projection is an analytic reconstruction algorithm designed to overcome the limitations of conventional back projection; it applies a convolution filter to remove blurring. It was, up until recently the primary method in cross-sectional imaging reconstruction.
Why is it called a sinogram?
The Radon transform data is often called a sinogram because the Radon transform of an off-center point source is a sinusoid. Consequently, the Radon transform of a number of small objects appears graphically as a number of blurred sine waves with different amplitudes and phases.
What is the purpose of sinogram or Fistulogram?
A fistulogram or sinogram is an x-ray procedure to view an abnormal passage (fistula/sinus) between two or more organs. It may include a passage from inside the body to an opening on the skin.