ABSTRACT
Tomographic imaging in Nuclear Medicine was invented in order to overcome the problems of the standard two-dimensional images acquisition. The mathematics underlying reconstruction tomography was published by J. Radon in 1917, but practical applications in medical imaging were developed later, in 1970s in the case of x-ray computed tomography. The most important reconstruction methods aim to give a realistic answer, applicable for the daily clinical use. These methods are based on a continuous modeling and the reconstruction process consists of the inversion of measurement equations. The main concept is that the medical image is the Radon Transformation of the radioactivity distribution in the region of interest. The most frequently used algorithm is the Filtered Back Projection. Analytic reconstruction algorithms are efficient and elegant but they are unable to handle complicated factors such as blurring and noise.
