Tomography is imaging by sections. By aquiring multiple 2-D images from multiple , a 3-D image may be reconstructed with the aid of a tomographic reconstruction applied by a computer. The device used to produce the images is called a tomograph, while the image produced is a tomogram. Several different tomographic methods are used in modern medicine for purposes. Of particular interest to us are techniques which use radionuclides. In SPECT ( photon computed tomography), the patient is injected with a that decays by gamma-ray emission. These gamma rays are detected by a camera, forming an image of the distribution of the in the body of the patient. Another tomographic method that uses radionuclides is PET ( emission ). In this method, the radionuclide which is injected decays by (positive beta-particle) emission. It does not take long for the positron to collide with an , anihiliating each other, producing two that travel off in (generally) opposite directions. These of gamma-rays are then detected by the PET scanner.

Computed Tomography (CT) is a medical imaging technique that uses X-rays to obtain structural and functional information about the human body.The digital geometry processing can be used to generate a three-dimensionalimage of the internal structures of the human body from a large series oftwo-dimensional X-ray images taken around a single axis of rotation

In which of these radiological examinations ionizing radiation is used?Question 33Select one:Digital subtraction angiographyUltrasoundMagnetic resonance imaging

The imaging technology device used to check for diseases or information in areas with cancer in the human body:-a.Geographical Position Systemb.Computed Tomography scanc.Computer Information Technology Scanningd.Positron Emission Tomography

Which of the following is a contrast X-ray technique?*magnetoencephalographyangiographystructural magnetic resonance imagingpositron emission tomographyfunctional MRI

X-rays are used in hospitals for computed tomography (CT) scans. (i) State one other medical use for X-rays. ______________________________________________________________ ______________________________________________________________(1) (ii) State a property of X-rays that makes them suitable for your answer in part (d)(i). ______________________________________________________________ ______________________________________________________________(1)